Merge #2763

2763: Index scheduler r=Kerollmops a=irevoire

Fix https://github.com/meilisearch/meilisearch/issues/2725

- [x] Durability of the tasks once an answer has been sent to the user.
- [x] Fix the analytics
- [x] Disable the auto-batching system.
- [x] Make sure the task scheduler run if there are tasks to process.
- [x] Auto-batching of enqueued tasks:
    - [x] Do not batch operations from two different indexes.
    - [x] Document addition.
    - [x] Document updates.
    - [x] Settings.
    - [x] Document deletion.
    - [x] Make sure that we only merge batches with the same index-creation rights:
        - [x] the batch either starts with a `yes`
        - [x] [we only batch `no`s together and stop batching when we encounter a `yes`](https://www.youtube.com/watch?v=O27mdRvR1GY)
        - [x] Unify the logic about `false` and `true` index creation rights.
- [ ] Execute all batch kind:
    - [x] Import dumps at startup time.
    - [x] Export dumps i.e. export the tasks queue.
    - [x] Document addition
    - [x] Document update
    - [x] Document deletion.
    - [x] Clear all documents.
    - [x] Update the settings of an index.
    - [ ] Merge multiple settings into a single one.
    - [x] Index update e.g. Create an Index, change an index primary key, delete an index.
    - [x] Cancel enqueued or processing tasks (with filters) (don't count tasks from forbidden indexes) (can't cancel a task with a higher or equal task_id than your own).
    - [x] Delete processed tasks from the task store (with filters) (don't count tasks from forbidden indexes) (can't flush a task with a higher or equal task_id than your own)
    - [x] Document addition + settings
    - [x] Document addition + settings + clear all documents
    - [x] anything + index deletion
    - [x] Snapshot
       - [x] Make the `SnapshotCreation` task visible.
       - [x] Snapshot tasks are scheduled by a detached thread.
       - [x] Only include update files that are useful.
    - [x] Check that statuses and details are correctly set. (ie; if you enqueue a `documentAddition`, is the `documentReceived` well set?)
- [x] Prioritize and reorder tasks i.e. Index deletion, Delete all the documents.
- [x] Always accept new tasks without blocking.
- [x] Fairly share the loads over the different indexes e.g. Always process the index queue with the lowest id.
- [x] Easily testable.
- [x] Well tested i.e. tasks reordering, tasks prioritizing, use atomic barriers to block the tasks for tests.
- [x] Dump
    - [x] Serialize the uuid as string in the keys
    - [x] Create a dump crate with getters and setters
    - [x] Serialize the API key in the dump task
    - [x] Get the instance-uuid in the dump task
- [x] List and filter tasks:
    - [x] Paginate the tasks.
    - [x] Filter by index name.
    - [x] Filter on the status, the enqueued, processing, and finished tasks.
    - [x] Filter on the type of task.
    - [x] Check that it works in `meilisearch-http`.
- [x] Think about [the index wrapper](2c4c14caa8/index/src/updates.rs (L269)) and probably move or remove it.
- [x] Reduce the amount of copy/paste for the batched operations by creating a sub-enum for the `Batch` enum.
- [x] Move the `IndexScheduler` in the lib.rs file.
- [x] Think about the `MilliError` type and probably remove it.
- [x] Remove the `index` crate entirely
- [x] Remove the `Kind` type from the `TaskView` and introduce another type, remove the `<Kind as FromStr>`.
- [x] Once the point above is done; remove the unreachable variant from the autobatchingkind
- [x] Rename the `Settings` task `Kind` to `SettingsUpdate`
- [x] Rename the `DumpExport` task `Kind` to `DumpExport`
- [x] Path the error message when deserializing a `Kind` and `Status`.
- [x] Check the version file when starting.
- [x] Copy the version file when creating snapshots.

---------

Once everything above is done;
- [ ] Check what happens with the update files i.e. when are they deleted.
    - [ ] When a TaskDeletion occurs
    - [ ] When a TaskCancelation
    - [ ] When a task is finished
    - [ ] When a task fails
- [ ] When importing a dump forward the date to milli
- [ ] Add tests for the snapshots.
- [ ] Look at all the places where we put _TODOs_.
- [ ] Rename a bunch of things, see https://github.com/meilisearch/meilisearch/pull/2917
- [ ] Ensure that when compiling meilisearch-http with `no-default-features` it doesn’t pull lindera etc
- [ ] Run a bunch of operations in a `tokio::spawn_blocking`
    - [ ] The search requests
- [ ] Issue to create once this is merged:
    - [ ] Realtime progressing status e.g. Websocket events (optional).
    - [ ] Implement an `Uuid` codec instead of using a `Bincode<Uuid>`.
    - [ ] Handle the dump-v1
    - [ ] When importing a dump v1 we could iterate over the whole task queue to find the creation and last update date
    - [ ] When importing a dump v2 we could iterate over the whole task queue to find the creation and last update date
    - [ ] When importing a dump v3 we could iterate over the whole task queue to find the creation and last update date
    - [ ] When importing a dump v4 we could iterate over the whole task queue to find the creation and last update date
    - [ ] When importing a dump v5 we could iterate over the whole task queue to find the creation and last update date

Co-authored-by: Tamo <tamo@meilisearch.com>
Co-authored-by: Kerollmops <clement@meilisearch.com>
Co-authored-by: Loïc Lecrenier <loic@meilisearch.com>

.gitignore

@@ -7,3 +7,10 @@
 /data.ms
 /snapshots
 /dumps
+
+
+# Snapshots
+## ... large
+*.full.snap
+##  ... unreviewed
+*.snap.new

.rustfmt.toml

@@ -0,0 +1,5 @@
+unstable_features = true
+
+use_small_heuristics = "max"
+imports_granularity = "Module"
+group_imports = "StdExternalCrate"

Cargo.toml

@@ -3,8 +3,11 @@ resolver = "2"
 members = [
     "meilisearch-http",
     "meilisearch-types",
-    "meilisearch-lib",
     "meilisearch-auth",
+    "meili-snap",
+    "index-scheduler",
+    "dump",
+    "file-store",
     "permissive-json-pointer",
 ]
 

dump/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+name = "dump"
+version = "0.29.0"
+edition = "2021"
+
+[dependencies]
+anyhow = "1.0.65"
+flate2 = "1.0.22"
+http = "0.2.8"
+log = "0.4.17"
+meilisearch-auth = { path = "../meilisearch-auth" }
+meilisearch-types = { path = "../meilisearch-types" }
+once_cell = "1.15.0"
+regex = "1.6.0"
+roaring = { version = "0.10.0", features = ["serde"] }
+serde = { version = "1.0.136", features = ["derive"] }
+serde_json = { version = "1.0.85", features = ["preserve_order"] }
+tar = "0.4.38"
+tempfile = "3.3.0"
+thiserror = "1.0.30"
+time = { version = "0.3.7", features = ["serde-well-known", "formatting", "parsing", "macros"] }
+uuid = { version = "1.1.2", features = ["serde", "v4"] }
+
+[dev-dependencies]
+big_s = "1.0.2"
+maplit = "1.0.2"
+meili-snap = { path = "../meili-snap" }
+meilisearch-types = { path = "../meilisearch-types" }

dump/README.md

@@ -0,0 +1,17 @@
+```
+dump
+├── indexes
+│   ├── cattos
+│   │   ├── documents.jsonl
+│   │   └── settings.json
+│   └── doggos
+│       ├── documents.jsonl
+│       └── settings.json
+├── instance-uid.uuid
+├── keys.jsonl
+├── metadata.json
+└── tasks
+    ├── update_files
+    │   └── [task_id].jsonl
+    └── queue.jsonl
+```

dump/src/error.rs

@@ -0,0 +1,36 @@
+use meilisearch_types::error::{Code, ErrorCode};
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub enum Error {
+    #[error("The version 1 of the dumps is not supported anymore. You can re-export your dump from a version between 0.21 and 0.24, or start fresh from a version 0.25 onwards.")]
+    DumpV1Unsupported,
+    #[error("Bad index name.")]
+    BadIndexName,
+    #[error("Malformed task.")]
+    MalformedTask,
+
+    #[error(transparent)]
+    Io(#[from] std::io::Error),
+    #[error(transparent)]
+    Serde(#[from] serde_json::Error),
+    #[error(transparent)]
+    Uuid(#[from] uuid::Error),
+}
+
+impl ErrorCode for Error {
+    fn error_code(&self) -> Code {
+        match self {
+            // Are these three really Internal errors?
+            // TODO look at that later.
+            Error::Io(_) => Code::Internal,
+            Error::Serde(_) => Code::Internal,
+            Error::Uuid(_) => Code::Internal,
+
+            // all these errors should never be raised when creating a dump, thus no error code should be associated.
+            Error::DumpV1Unsupported => Code::Internal,
+            Error::BadIndexName => Code::Internal,
+            Error::MalformedTask => Code::Internal,
+        }
+    }
+}

dump/src/lib.rs

@@ -0,0 +1,465 @@
+#![allow(clippy::type_complexity)]
+#![allow(clippy::wrong_self_convention)]
+
+use meilisearch_types::error::ResponseError;
+use meilisearch_types::keys::Key;
+use meilisearch_types::milli::update::IndexDocumentsMethod;
+use meilisearch_types::settings::Unchecked;
+use meilisearch_types::tasks::{Details, IndexSwap, KindWithContent, Status, Task, TaskId};
+use meilisearch_types::InstanceUid;
+use roaring::RoaringBitmap;
+use serde::{Deserialize, Serialize};
+use time::OffsetDateTime;
+
+mod error;
+mod reader;
+mod writer;
+
+pub use error::Error;
+pub use reader::{DumpReader, UpdateFile};
+pub use writer::DumpWriter;
+
+const CURRENT_DUMP_VERSION: Version = Version::V6;
+
+type Result<T> = std::result::Result<T, Error>;
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct Metadata {
+    pub dump_version: Version,
+    pub db_version: String,
+    #[serde(with = "time::serde::rfc3339")]
+    pub dump_date: OffsetDateTime,
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct IndexMetadata {
+    pub uid: String,
+    pub primary_key: Option<String>,
+    #[serde(with = "time::serde::rfc3339")]
+    pub created_at: OffsetDateTime,
+    #[serde(with = "time::serde::rfc3339")]
+    pub updated_at: OffsetDateTime,
+}
+
+#[derive(Debug, PartialEq, Eq, Deserialize, Serialize)]
+pub enum Version {
+    V1,
+    V2,
+    V3,
+    V4,
+    V5,
+    V6,
+}
+
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct TaskDump {
+    pub uid: TaskId,
+    #[serde(default)]
+    pub index_uid: Option<String>,
+    pub status: Status,
+    #[serde(rename = "type")]
+    pub kind: KindDump,
+
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub canceled_by: Option<TaskId>,
+
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub details: Option<Details>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub error: Option<ResponseError>,
+
+    #[serde(with = "time::serde::rfc3339")]
+    pub enqueued_at: OffsetDateTime,
+    #[serde(
+        with = "time::serde::rfc3339::option",
+        skip_serializing_if = "Option::is_none",
+        default
+    )]
+    pub started_at: Option<OffsetDateTime>,
+    #[serde(
+        with = "time::serde::rfc3339::option",
+        skip_serializing_if = "Option::is_none",
+        default
+    )]
+    pub finished_at: Option<OffsetDateTime>,
+}
+
+// A `Kind` specific version made for the dump. If modified you may break the dump.
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub enum KindDump {
+    DocumentImport {
+        primary_key: Option<String>,
+        method: IndexDocumentsMethod,
+        documents_count: u64,
+        allow_index_creation: bool,
+    },
+    DocumentDeletion {
+        documents_ids: Vec<String>,
+    },
+    DocumentClear,
+    Settings {
+        settings: Box<meilisearch_types::settings::Settings<Unchecked>>,
+        is_deletion: bool,
+        allow_index_creation: bool,
+    },
+    IndexDeletion,
+    IndexCreation {
+        primary_key: Option<String>,
+    },
+    IndexUpdate {
+        primary_key: Option<String>,
+    },
+    IndexSwap {
+        swaps: Vec<IndexSwap>,
+    },
+    TaskCancelation {
+        query: String,
+        tasks: RoaringBitmap,
+    },
+    TasksDeletion {
+        query: String,
+        tasks: RoaringBitmap,
+    },
+    DumpCreation {
+        dump_uid: String,
+        keys: Vec<Key>,
+        instance_uid: Option<InstanceUid>,
+    },
+    SnapshotCreation,
+}
+
+impl From<Task> for TaskDump {
+    fn from(task: Task) -> Self {
+        TaskDump {
+            uid: task.uid,
+            index_uid: task.index_uid().map(|uid| uid.to_string()),
+            status: task.status,
+            kind: task.kind.into(),
+            canceled_by: task.canceled_by,
+            details: task.details,
+            error: task.error,
+            enqueued_at: task.enqueued_at,
+            started_at: task.started_at,
+            finished_at: task.finished_at,
+        }
+    }
+}
+
+impl From<KindWithContent> for KindDump {
+    fn from(kind: KindWithContent) -> Self {
+        match kind {
+            KindWithContent::DocumentAdditionOrUpdate {
+                primary_key,
+                method,
+                documents_count,
+                allow_index_creation,
+                ..
+            } => KindDump::DocumentImport {
+                primary_key,
+                method,
+                documents_count,
+                allow_index_creation,
+            },
+            KindWithContent::DocumentDeletion { documents_ids, .. } => {
+                KindDump::DocumentDeletion { documents_ids }
+            }
+            KindWithContent::DocumentClear { .. } => KindDump::DocumentClear,
+            KindWithContent::SettingsUpdate {
+                new_settings,
+                is_deletion,
+                allow_index_creation,
+                ..
+            } => KindDump::Settings { settings: new_settings, is_deletion, allow_index_creation },
+            KindWithContent::IndexDeletion { .. } => KindDump::IndexDeletion,
+            KindWithContent::IndexCreation { primary_key, .. } => {
+                KindDump::IndexCreation { primary_key }
+            }
+            KindWithContent::IndexUpdate { primary_key, .. } => {
+                KindDump::IndexUpdate { primary_key }
+            }
+            KindWithContent::IndexSwap { swaps } => KindDump::IndexSwap { swaps },
+            KindWithContent::TaskCancelation { query, tasks } => {
+                KindDump::TaskCancelation { query, tasks }
+            }
+            KindWithContent::TaskDeletion { query, tasks } => {
+                KindDump::TasksDeletion { query, tasks }
+            }
+            KindWithContent::DumpCreation { dump_uid, keys, instance_uid } => {
+                KindDump::DumpCreation { dump_uid, keys, instance_uid }
+            }
+            KindWithContent::SnapshotCreation => KindDump::SnapshotCreation,
+        }
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::{Seek, SeekFrom};
+    use std::str::FromStr;
+
+    use big_s::S;
+    use maplit::btreeset;
+    use meilisearch_types::index_uid::IndexUid;
+    use meilisearch_types::keys::{Action, Key};
+    use meilisearch_types::milli::update::Setting;
+    use meilisearch_types::milli::{self};
+    use meilisearch_types::settings::{Checked, Settings};
+    use meilisearch_types::star_or::StarOr;
+    use meilisearch_types::tasks::{Details, Status};
+    use serde_json::{json, Map, Value};
+    use time::macros::datetime;
+    use uuid::Uuid;
+
+    use crate::reader::Document;
+    use crate::{DumpReader, DumpWriter, IndexMetadata, KindDump, TaskDump, Version};
+
+    pub fn create_test_instance_uid() -> Uuid {
+        Uuid::parse_str("9e15e977-f2ae-4761-943f-1eaf75fd736d").unwrap()
+    }
+
+    pub fn create_test_index_metadata() -> IndexMetadata {
+        IndexMetadata {
+            uid: S("doggo"),
+            primary_key: None,
+            created_at: datetime!(2022-11-20 12:00 UTC),
+            updated_at: datetime!(2022-11-21 00:00 UTC),
+        }
+    }
+
+    pub fn create_test_documents() -> Vec<Map<String, Value>> {
+        vec![
+            json!({ "id": 1, "race": "golden retriever", "name": "paul", "age": 4 })
+                .as_object()
+                .unwrap()
+                .clone(),
+            json!({ "id": 2, "race": "bernese mountain", "name": "tamo", "age": 6 })
+                .as_object()
+                .unwrap()
+                .clone(),
+            json!({ "id": 3, "race": "great pyrenees", "name": "patou", "age": 5 })
+                .as_object()
+                .unwrap()
+                .clone(),
+        ]
+    }
+
+    pub fn create_test_settings() -> Settings<Checked> {
+        let settings = Settings {
+            displayed_attributes: Setting::Set(vec![S("race"), S("name")]),
+            searchable_attributes: Setting::Set(vec![S("name"), S("race")]),
+            filterable_attributes: Setting::Set(btreeset! { S("race"), S("age") }),
+            sortable_attributes: Setting::Set(btreeset! { S("age") }),
+            ranking_rules: Setting::NotSet,
+            stop_words: Setting::NotSet,
+            synonyms: Setting::NotSet,
+            distinct_attribute: Setting::NotSet,
+            typo_tolerance: Setting::NotSet,
+            faceting: Setting::NotSet,
+            pagination: Setting::NotSet,
+            _kind: std::marker::PhantomData,
+        };
+        settings.check()
+    }
+
+    pub fn create_test_tasks() -> Vec<(TaskDump, Option<Vec<Document>>)> {
+        vec![
+            (
+                TaskDump {
+                    uid: 0,
+                    index_uid: Some(S("doggo")),
+                    status: Status::Succeeded,
+                    kind: KindDump::DocumentImport {
+                        method: milli::update::IndexDocumentsMethod::UpdateDocuments,
+                        allow_index_creation: true,
+                        primary_key: Some(S("bone")),
+                        documents_count: 12,
+                    },
+                    canceled_by: None,
+                    details: Some(Details::DocumentAdditionOrUpdate {
+                        received_documents: 12,
+                        indexed_documents: Some(10),
+                    }),
+                    error: None,
+                    enqueued_at: datetime!(2022-11-11 0:00 UTC),
+                    started_at: Some(datetime!(2022-11-20 0:00 UTC)),
+                    finished_at: Some(datetime!(2022-11-21 0:00 UTC)),
+                },
+                None,
+            ),
+            (
+                TaskDump {
+                    uid: 1,
+                    index_uid: Some(S("doggo")),
+                    status: Status::Enqueued,
+                    kind: KindDump::DocumentImport {
+                        method: milli::update::IndexDocumentsMethod::UpdateDocuments,
+                        allow_index_creation: true,
+                        primary_key: None,
+                        documents_count: 2,
+                    },
+                    canceled_by: None,
+                    details: Some(Details::DocumentAdditionOrUpdate {
+                        received_documents: 2,
+                        indexed_documents: None,
+                    }),
+                    error: None,
+                    enqueued_at: datetime!(2022-11-11 0:00 UTC),
+                    started_at: None,
+                    finished_at: None,
+                },
+                Some(vec![
+                    json!({ "id": 4, "race": "leonberg" }).as_object().unwrap().clone(),
+                    json!({ "id": 5, "race": "patou" }).as_object().unwrap().clone(),
+                ]),
+            ),
+            (
+                TaskDump {
+                    uid: 5,
+                    index_uid: Some(S("catto")),
+                    status: Status::Enqueued,
+                    kind: KindDump::IndexDeletion,
+                    canceled_by: None,
+                    details: None,
+                    error: None,
+                    enqueued_at: datetime!(2022-11-15 0:00 UTC),
+                    started_at: None,
+                    finished_at: None,
+                },
+                None,
+            ),
+        ]
+    }
+
+    pub fn create_test_api_keys() -> Vec<Key> {
+        vec![
+            Key {
+                description: Some(S("The main key to manage all the doggos")),
+                name: Some(S("doggos_key")),
+                uid: Uuid::from_str("9f8a34da-b6b2-42f0-939b-dbd4c3448655").unwrap(),
+                actions: vec![Action::DocumentsAll],
+                indexes: vec![StarOr::Other(IndexUid::from_str("doggos").unwrap())],
+                expires_at: Some(datetime!(4130-03-14 12:21 UTC)),
+                created_at: datetime!(1960-11-15 0:00 UTC),
+                updated_at: datetime!(2022-11-10 0:00 UTC),
+            },
+            Key {
+                description: Some(S("The master key for everything and even the doggos")),
+                name: Some(S("master_key")),
+                uid: Uuid::from_str("4622f717-1c00-47bb-a494-39d76a49b591").unwrap(),
+                actions: vec![Action::All],
+                indexes: vec![StarOr::Star],
+                expires_at: None,
+                created_at: datetime!(0000-01-01 00:01 UTC),
+                updated_at: datetime!(1964-05-04 17:25 UTC),
+            },
+            Key {
+                description: Some(S("The useless key to for nothing nor the doggos")),
+                name: Some(S("useless_key")),
+                uid: Uuid::from_str("fb80b58b-0a34-412f-8ba7-1ce868f8ac5c").unwrap(),
+                actions: vec![],
+                indexes: vec![],
+                expires_at: None,
+                created_at: datetime!(400-02-29 0:00 UTC),
+                updated_at: datetime!(1024-02-29 0:00 UTC),
+            },
+        ]
+    }
+
+    pub fn create_test_dump() -> File {
+        let instance_uid = create_test_instance_uid();
+        let dump = DumpWriter::new(Some(instance_uid)).unwrap();
+
+        // ========== Adding an index
+        let documents = create_test_documents();
+        let settings = create_test_settings();
+
+        let mut index = dump.create_index("doggos", &create_test_index_metadata()).unwrap();
+        for document in &documents {
+            index.push_document(document).unwrap();
+        }
+        index.flush().unwrap();
+        index.settings(&settings).unwrap();
+
+        // ========== pushing the task queue
+        let tasks = create_test_tasks();
+
+        let mut task_queue = dump.create_tasks_queue().unwrap();
+        for (task, update_file) in &tasks {
+            let mut update = task_queue.push_task(task).unwrap();
+            if let Some(update_file) = update_file {
+                for u in update_file {
+                    update.push_document(u).unwrap();
+                }
+            }
+        }
+        task_queue.flush().unwrap();
+
+        // ========== pushing the api keys
+        let api_keys = create_test_api_keys();
+
+        let mut keys = dump.create_keys().unwrap();
+        for key in &api_keys {
+            keys.push_key(key).unwrap();
+        }
+        keys.flush().unwrap();
+
+        // create the dump
+        let mut file = tempfile::tempfile().unwrap();
+        dump.persist_to(&mut file).unwrap();
+        file.seek(SeekFrom::Start(0)).unwrap();
+
+        file
+    }
+
+    #[test]
+    #[ignore]
+    fn test_creating_and_read_dump() {
+        let mut file = create_test_dump();
+        let mut dump = DumpReader::open(&mut file).unwrap();
+
+        // ==== checking the top level infos
+        assert_eq!(dump.version(), Version::V6);
+        assert!(dump.date().is_some());
+        assert_eq!(dump.instance_uid().unwrap().unwrap(), create_test_instance_uid());
+
+        // ==== checking the index
+        let mut indexes = dump.indexes().unwrap();
+        let mut index = indexes.next().unwrap().unwrap();
+        assert!(indexes.next().is_none()); // there was only one index in the dump
+
+        for (document, expected) in index.documents().unwrap().zip(create_test_documents()) {
+            assert_eq!(document.unwrap(), expected);
+        }
+        assert_eq!(index.settings().unwrap(), create_test_settings());
+        assert_eq!(index.metadata(), &create_test_index_metadata());
+
+        drop(index);
+        drop(indexes);
+
+        // ==== checking the task queue
+        for (task, expected) in dump.tasks().unwrap().zip(create_test_tasks()) {
+            let (task, content_file) = task.unwrap();
+            assert_eq!(task, expected.0);
+
+            if let Some(expected_update) = expected.1 {
+                assert!(
+                    content_file.is_some(),
+                    "A content file was expected for the task {}.",
+                    expected.0.uid
+                );
+                let updates = content_file.unwrap().collect::<Result<Vec<_>, _>>().unwrap();
+                assert_eq!(updates, expected_update);
+            }
+        }
+
+        // ==== checking the keys
+        for (key, expected) in dump.keys().unwrap().zip(create_test_api_keys()) {
+            assert_eq!(key.unwrap(), expected);
+        }
+    }
+}

dump/src/reader/compat/mod.rs

@@ -0,0 +1,4 @@
+pub mod v2_to_v3;
+pub mod v3_to_v4;
+pub mod v4_to_v5;
+pub mod v5_to_v6;

dump/src/reader/compat/v2_to_v3.rs

@@ -0,0 +1,480 @@
+use std::convert::TryInto;
+use std::str::FromStr;
+
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+use super::v3_to_v4::CompatV3ToV4;
+use crate::reader::{v2, v3, Document};
+use crate::Result;
+
+pub struct CompatV2ToV3 {
+    pub from: v2::V2Reader,
+}
+
+impl CompatV2ToV3 {
+    pub fn new(v2: v2::V2Reader) -> CompatV2ToV3 {
+        CompatV2ToV3 { from: v2 }
+    }
+
+    pub fn index_uuid(&self) -> Vec<v3::meta::IndexUuid> {
+        self.from
+            .index_uuid()
+            .into_iter()
+            .map(|index| v3::meta::IndexUuid { uid: index.uid, uuid: index.uuid })
+            .collect()
+    }
+
+    pub fn to_v4(self) -> CompatV3ToV4 {
+        CompatV3ToV4::Compat(self)
+    }
+
+    pub fn version(&self) -> crate::Version {
+        self.from.version()
+    }
+
+    pub fn date(&self) -> Option<time::OffsetDateTime> {
+        self.from.date()
+    }
+
+    pub fn instance_uid(&self) -> Result<Option<uuid::Uuid>> {
+        Ok(None)
+    }
+
+    pub fn indexes(&self) -> Result<impl Iterator<Item = Result<CompatIndexV2ToV3>> + '_> {
+        Ok(self.from.indexes()?.map(|index_reader| -> Result<_> {
+            let compat = CompatIndexV2ToV3::new(index_reader?);
+            Ok(compat)
+        }))
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Box<
+        dyn Iterator<Item = Result<(v3::Task, Option<Box<dyn Iterator<Item = Result<Document>>>>)>>
+            + '_,
+    > {
+        let _indexes = self.from.index_uuid.clone();
+
+        Box::new(
+            self.from
+                .tasks()
+                .map(move |task| {
+                    task.map(|(task, content_file)| {
+                        let task = v3::Task { uuid: task.uuid, update: task.update.into() };
+
+                        Some((
+                            task,
+                            content_file.map(|content_file| {
+                                Box::new(content_file) as Box<dyn Iterator<Item = Result<Document>>>
+                            }),
+                        ))
+                    })
+                })
+                .filter_map(|res| res.transpose()),
+        )
+    }
+}
+
+pub struct CompatIndexV2ToV3 {
+    from: v2::V2IndexReader,
+}
+
+impl CompatIndexV2ToV3 {
+    pub fn new(v2: v2::V2IndexReader) -> CompatIndexV2ToV3 {
+        CompatIndexV2ToV3 { from: v2 }
+    }
+
+    pub fn metadata(&self) -> &crate::IndexMetadata {
+        self.from.metadata()
+    }
+
+    pub fn documents(&mut self) -> Result<Box<dyn Iterator<Item = Result<Document>> + '_>> {
+        self.from
+            .documents()
+            .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<Document>> + '_>)
+    }
+
+    pub fn settings(&mut self) -> Result<v3::Settings<v3::Checked>> {
+        Ok(v3::Settings::<v3::Unchecked>::from(self.from.settings()?).check())
+    }
+}
+
+impl From<v2::updates::UpdateStatus> for v3::updates::UpdateStatus {
+    fn from(update: v2::updates::UpdateStatus) -> Self {
+        match update {
+            v2::updates::UpdateStatus::Processing(processing) => {
+                match (processing.from.meta.clone(), processing.from.content).try_into() {
+                    Ok(meta) => v3::updates::UpdateStatus::Processing(v3::updates::Processing {
+                        from: v3::updates::Enqueued {
+                            update_id: processing.from.update_id,
+                            meta,
+                            enqueued_at: processing.from.enqueued_at,
+                        },
+                        started_processing_at: processing.started_processing_at,
+                    }),
+                    Err(e) => {
+                        log::warn!("Error with task {}: {}", processing.from.update_id, e);
+                        log::warn!("Task will be marked as `Failed`.");
+                        v3::updates::UpdateStatus::Failed(v3::updates::Failed {
+                            from: v3::updates::Processing {
+                                from: v3::updates::Enqueued {
+                                    update_id: processing.from.update_id,
+                                    meta: update_from_unchecked_update_meta(processing.from.meta),
+                                    enqueued_at: processing.from.enqueued_at,
+                                },
+                                started_processing_at: processing.started_processing_at,
+                            },
+                            msg: e.to_string(),
+                            code: v3::Code::MalformedDump,
+                            failed_at: OffsetDateTime::now_utc(),
+                        })
+                    }
+                }
+            }
+            v2::updates::UpdateStatus::Enqueued(enqueued) => {
+                match (enqueued.meta.clone(), enqueued.content).try_into() {
+                    Ok(meta) => v3::updates::UpdateStatus::Enqueued(v3::updates::Enqueued {
+                        update_id: enqueued.update_id,
+                        meta,
+                        enqueued_at: enqueued.enqueued_at,
+                    }),
+                    Err(e) => {
+                        log::warn!("Error with task {}: {}", enqueued.update_id, e);
+                        log::warn!("Task will be marked as `Failed`.");
+                        v3::updates::UpdateStatus::Failed(v3::updates::Failed {
+                            from: v3::updates::Processing {
+                                from: v3::updates::Enqueued {
+                                    update_id: enqueued.update_id,
+                                    meta: update_from_unchecked_update_meta(enqueued.meta),
+                                    enqueued_at: enqueued.enqueued_at,
+                                },
+                                started_processing_at: OffsetDateTime::now_utc(),
+                            },
+                            msg: e.to_string(),
+                            code: v3::Code::MalformedDump,
+                            failed_at: OffsetDateTime::now_utc(),
+                        })
+                    }
+                }
+            }
+            v2::updates::UpdateStatus::Processed(processed) => {
+                v3::updates::UpdateStatus::Processed(v3::updates::Processed {
+                    success: processed.success.into(),
+                    processed_at: processed.processed_at,
+                    from: v3::updates::Processing {
+                        from: v3::updates::Enqueued {
+                            update_id: processed.from.from.update_id,
+                            // since we're never going to read the content_file again it's ok to generate a fake one.
+                            meta: update_from_unchecked_update_meta(processed.from.from.meta),
+                            enqueued_at: processed.from.from.enqueued_at,
+                        },
+                        started_processing_at: processed.from.started_processing_at,
+                    },
+                })
+            }
+            v2::updates::UpdateStatus::Aborted(aborted) => {
+                v3::updates::UpdateStatus::Aborted(v3::updates::Aborted {
+                    from: v3::updates::Enqueued {
+                        update_id: aborted.from.update_id,
+                        // since we're never going to read the content_file again it's ok to generate a fake one.
+                        meta: update_from_unchecked_update_meta(aborted.from.meta),
+                        enqueued_at: aborted.from.enqueued_at,
+                    },
+                    aborted_at: aborted.aborted_at,
+                })
+            }
+            v2::updates::UpdateStatus::Failed(failed) => {
+                v3::updates::UpdateStatus::Failed(v3::updates::Failed {
+                    from: v3::updates::Processing {
+                        from: v3::updates::Enqueued {
+                            update_id: failed.from.from.update_id,
+                            // since we're never going to read the content_file again it's ok to generate a fake one.
+                            meta: update_from_unchecked_update_meta(failed.from.from.meta),
+                            enqueued_at: failed.from.from.enqueued_at,
+                        },
+                        started_processing_at: failed.from.started_processing_at,
+                    },
+                    msg: failed.error.message,
+                    code: failed.error.error_code.into(),
+                    failed_at: failed.failed_at,
+                })
+            }
+        }
+    }
+}
+
+impl TryFrom<(v2::updates::UpdateMeta, Option<Uuid>)> for v3::updates::Update {
+    type Error = crate::Error;
+
+    fn try_from((update, uuid): (v2::updates::UpdateMeta, Option<Uuid>)) -> Result<Self> {
+        Ok(match update {
+            v2::updates::UpdateMeta::DocumentsAddition { method, format: _, primary_key }
+                if uuid.is_some() =>
+            {
+                v3::updates::Update::DocumentAddition {
+                    primary_key,
+                    method: match method {
+                        v2::updates::IndexDocumentsMethod::ReplaceDocuments => {
+                            v3::updates::IndexDocumentsMethod::ReplaceDocuments
+                        }
+                        v2::updates::IndexDocumentsMethod::UpdateDocuments => {
+                            v3::updates::IndexDocumentsMethod::UpdateDocuments
+                        }
+                    },
+                    content_uuid: uuid.unwrap(),
+                }
+            }
+            v2::updates::UpdateMeta::DocumentsAddition { .. } => {
+                return Err(crate::Error::MalformedTask)
+            }
+            v2::updates::UpdateMeta::ClearDocuments => v3::updates::Update::ClearDocuments,
+            v2::updates::UpdateMeta::DeleteDocuments { ids } => {
+                v3::updates::Update::DeleteDocuments(ids)
+            }
+            v2::updates::UpdateMeta::Settings(settings) => {
+                v3::updates::Update::Settings(settings.into())
+            }
+        })
+    }
+}
+
+pub fn update_from_unchecked_update_meta(update: v2::updates::UpdateMeta) -> v3::updates::Update {
+    match update {
+        v2::updates::UpdateMeta::DocumentsAddition { method, format: _, primary_key } => {
+            v3::updates::Update::DocumentAddition {
+                primary_key,
+                method: match method {
+                    v2::updates::IndexDocumentsMethod::ReplaceDocuments => {
+                        v3::updates::IndexDocumentsMethod::ReplaceDocuments
+                    }
+                    v2::updates::IndexDocumentsMethod::UpdateDocuments => {
+                        v3::updates::IndexDocumentsMethod::UpdateDocuments
+                    }
+                },
+                // we use this special uuid so we can recognize it if one day there is a bug related to this field.
+                content_uuid: Uuid::from_str("00112233-4455-6677-8899-aabbccddeeff").unwrap(),
+            }
+        }
+        v2::updates::UpdateMeta::ClearDocuments => v3::updates::Update::ClearDocuments,
+        v2::updates::UpdateMeta::DeleteDocuments { ids } => {
+            v3::updates::Update::DeleteDocuments(ids)
+        }
+        v2::updates::UpdateMeta::Settings(settings) => {
+            v3::updates::Update::Settings(settings.into())
+        }
+    }
+}
+
+impl From<v2::updates::UpdateResult> for v3::updates::UpdateResult {
+    fn from(result: v2::updates::UpdateResult) -> Self {
+        match result {
+            v2::updates::UpdateResult::DocumentsAddition(addition) => {
+                v3::updates::UpdateResult::DocumentsAddition(v3::updates::DocumentAdditionResult {
+                    nb_documents: addition.nb_documents,
+                })
+            }
+            v2::updates::UpdateResult::DocumentDeletion { deleted } => {
+                v3::updates::UpdateResult::DocumentDeletion { deleted }
+            }
+            v2::updates::UpdateResult::Other => v3::updates::UpdateResult::Other,
+        }
+    }
+}
+
+impl From<String> for v3::Code {
+    fn from(code: String) -> Self {
+        match code.as_ref() {
+            "create_index" => v3::Code::CreateIndex,
+            "index_already_exists" => v3::Code::IndexAlreadyExists,
+            "index_not_found" => v3::Code::IndexNotFound,
+            "invalid_index_uid" => v3::Code::InvalidIndexUid,
+            "invalid_state" => v3::Code::InvalidState,
+            "missing_primary_key" => v3::Code::MissingPrimaryKey,
+            "primary_key_already_present" => v3::Code::PrimaryKeyAlreadyPresent,
+            "max_fields_limit_exceeded" => v3::Code::MaxFieldsLimitExceeded,
+            "missing_document_id" => v3::Code::MissingDocumentId,
+            "invalid_document_id" => v3::Code::InvalidDocumentId,
+            "filter" => v3::Code::Filter,
+            "sort" => v3::Code::Sort,
+            "bad_parameter" => v3::Code::BadParameter,
+            "bad_request" => v3::Code::BadRequest,
+            "database_size_limit_reached" => v3::Code::DatabaseSizeLimitReached,
+            "document_not_found" => v3::Code::DocumentNotFound,
+            "internal" => v3::Code::Internal,
+            "invalid_geo_field" => v3::Code::InvalidGeoField,
+            "invalid_ranking_rule" => v3::Code::InvalidRankingRule,
+            "invalid_store" => v3::Code::InvalidStore,
+            "invalid_token" => v3::Code::InvalidToken,
+            "missing_authorization_header" => v3::Code::MissingAuthorizationHeader,
+            "no_space_left_on_device" => v3::Code::NoSpaceLeftOnDevice,
+            "dump_not_found" => v3::Code::DumpNotFound,
+            "task_not_found" => v3::Code::TaskNotFound,
+            "payload_too_large" => v3::Code::PayloadTooLarge,
+            "retrieve_document" => v3::Code::RetrieveDocument,
+            "search_documents" => v3::Code::SearchDocuments,
+            "unsupported_media_type" => v3::Code::UnsupportedMediaType,
+            "dump_already_in_progress" => v3::Code::DumpAlreadyInProgress,
+            "dump_process_failed" => v3::Code::DumpProcessFailed,
+            "invalid_content_type" => v3::Code::InvalidContentType,
+            "missing_content_type" => v3::Code::MissingContentType,
+            "malformed_payload" => v3::Code::MalformedPayload,
+            "missing_payload" => v3::Code::MissingPayload,
+            other => {
+                log::warn!("Unknown error code {}", other);
+                v3::Code::UnretrievableErrorCode
+            }
+        }
+    }
+}
+
+fn option_to_setting<T>(opt: Option<Option<T>>) -> v3::Setting<T> {
+    match opt {
+        Some(Some(t)) => v3::Setting::Set(t),
+        None => v3::Setting::NotSet,
+        Some(None) => v3::Setting::Reset,
+    }
+}
+
+impl<T> From<v2::Settings<T>> for v3::Settings<v3::Unchecked> {
+    fn from(settings: v2::Settings<T>) -> Self {
+        v3::Settings {
+            displayed_attributes: option_to_setting(settings.displayed_attributes),
+            searchable_attributes: option_to_setting(settings.searchable_attributes),
+            filterable_attributes: option_to_setting(settings.filterable_attributes)
+                .map(|f| f.into_iter().collect()),
+            sortable_attributes: v3::Setting::NotSet,
+            ranking_rules: option_to_setting(settings.ranking_rules).map(|criteria| {
+                criteria.into_iter().map(|criterion| patch_ranking_rules(&criterion)).collect()
+            }),
+            stop_words: option_to_setting(settings.stop_words),
+            synonyms: option_to_setting(settings.synonyms),
+            distinct_attribute: option_to_setting(settings.distinct_attribute),
+            _kind: std::marker::PhantomData,
+        }
+    }
+}
+
+fn patch_ranking_rules(ranking_rule: &str) -> String {
+    match v2::settings::Criterion::from_str(ranking_rule) {
+        Ok(v2::settings::Criterion::Words) => String::from("words"),
+        Ok(v2::settings::Criterion::Typo) => String::from("typo"),
+        Ok(v2::settings::Criterion::Proximity) => String::from("proximity"),
+        Ok(v2::settings::Criterion::Attribute) => String::from("attribute"),
+        Ok(v2::settings::Criterion::Exactness) => String::from("exactness"),
+        Ok(v2::settings::Criterion::Asc(name)) => format!("{name}:asc"),
+        Ok(v2::settings::Criterion::Desc(name)) => format!("{name}:desc"),
+        // we want to forward the error to the current version of meilisearch
+        Err(_) => ranking_rule.to_string(),
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::BufReader;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use tempfile::TempDir;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn compat_v2_v3() {
+        let dump = File::open("tests/assets/v2.dump").unwrap();
+        let dir = TempDir::new().unwrap();
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(dir.path()).unwrap();
+
+        let mut dump = v2::V2Reader::open(dir).unwrap().to_v3();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-09 20:27:59.904096267 +00:00:00");
+
+        // tasks
+        let tasks = dump.tasks().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, mut update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"9507711db47c7171c79bc6d57d0bed79");
+        assert_eq!(update_files.len(), 9);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        let update_file = update_files.remove(0).unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(update_file), @"7b8889539b669c7b9ddba448bafa385d");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies2 = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"54b3d7a0d96de35427d867fa17164a99");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"548284a84de510f71e88e6cdea495cf5");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"ae7c5ade2243a553152dab2f354e9095");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d153b5a81d8b3cdcbe1dec270b574022");
+
+        // movies2
+        insta::assert_json_snapshot!(movies2.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies_2",
+          "primaryKey": null,
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies2.settings()), @"1be82b894556d23953af557b6a328a58");
+        let documents = movies2.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 0);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d751713988987e9331980363e24189ce");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"1be82b894556d23953af557b6a328a58");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/compat/v3_to_v4.rs

@@ -0,0 +1,450 @@
+use super::v2_to_v3::{CompatIndexV2ToV3, CompatV2ToV3};
+use super::v4_to_v5::CompatV4ToV5;
+use crate::reader::{v3, v4, UpdateFile};
+use crate::Result;
+
+pub enum CompatV3ToV4 {
+    V3(v3::V3Reader),
+    Compat(CompatV2ToV3),
+}
+
+impl CompatV3ToV4 {
+    pub fn new(v3: v3::V3Reader) -> CompatV3ToV4 {
+        CompatV3ToV4::V3(v3)
+    }
+
+    pub fn to_v5(self) -> CompatV4ToV5 {
+        CompatV4ToV5::Compat(self)
+    }
+
+    pub fn version(&self) -> crate::Version {
+        match self {
+            CompatV3ToV4::V3(v3) => v3.version(),
+            CompatV3ToV4::Compat(compat) => compat.version(),
+        }
+    }
+
+    pub fn date(&self) -> Option<time::OffsetDateTime> {
+        match self {
+            CompatV3ToV4::V3(v3) => v3.date(),
+            CompatV3ToV4::Compat(compat) => compat.date(),
+        }
+    }
+
+    pub fn instance_uid(&self) -> Result<Option<uuid::Uuid>> {
+        Ok(None)
+    }
+
+    pub fn indexes(&self) -> Result<impl Iterator<Item = Result<CompatIndexV3ToV4>> + '_> {
+        Ok(match self {
+            CompatV3ToV4::V3(v3) => {
+                Box::new(v3.indexes()?.map(|index| index.map(CompatIndexV3ToV4::from)))
+                    as Box<dyn Iterator<Item = Result<CompatIndexV3ToV4>> + '_>
+            }
+
+            CompatV3ToV4::Compat(compat) => {
+                Box::new(compat.indexes()?.map(|index| index.map(CompatIndexV3ToV4::from)))
+                    as Box<dyn Iterator<Item = Result<CompatIndexV3ToV4>> + '_>
+            }
+        })
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Box<dyn Iterator<Item = Result<(v4::Task, Option<Box<UpdateFile>>)>> + '_> {
+        let indexes = match self {
+            CompatV3ToV4::V3(v3) => v3.index_uuid(),
+            CompatV3ToV4::Compat(compat) => compat.index_uuid(),
+        };
+        let tasks = match self {
+            CompatV3ToV4::V3(v3) => v3.tasks(),
+            CompatV3ToV4::Compat(compat) => compat.tasks(),
+        };
+
+        Box::new(
+            tasks
+                // we need to override the old task ids that were generated
+                // by index in favor of a global unique incremental ID.
+                .enumerate()
+                .map(move |(task_id, task)| {
+                    task.map(|(task, content_file)| {
+                        let index_uid = indexes
+                            .iter()
+                            .find(|index| index.uuid == task.uuid)
+                            .map(|index| index.uid.clone());
+
+                        let index_uid = match index_uid {
+                            Some(uid) => uid,
+                            None => {
+                                log::warn!(
+                                    "Error while importing the update {}.",
+                                    task.update.id()
+                                );
+                                log::warn!(
+                                    "The index associated to the uuid `{}` could not be retrieved.",
+                                    task.uuid.to_string()
+                                );
+                                if task.update.is_finished() {
+                                    // we're fucking with his history but not his data, that's ok-ish.
+                                    log::warn!("The index-uuid will be set as `unknown`.");
+                                    String::from("unknown")
+                                } else {
+                                    log::warn!("The task will be ignored.");
+                                    return None;
+                                }
+                            }
+                        };
+
+                        let task = v4::Task {
+                            id: task_id as u32,
+                            index_uid: v4::meta::IndexUid(index_uid),
+                            content: match task.update.meta() {
+                                v3::Kind::DeleteDocuments(documents) => {
+                                    v4::tasks::TaskContent::DocumentDeletion(
+                                        v4::tasks::DocumentDeletion::Ids(documents.clone()),
+                                    )
+                                }
+                                v3::Kind::DocumentAddition {
+                                    primary_key,
+                                    method,
+                                    content_uuid,
+                                } => v4::tasks::TaskContent::DocumentAddition {
+                                    merge_strategy: match method {
+                                        v3::updates::IndexDocumentsMethod::ReplaceDocuments => {
+                                            v4::tasks::IndexDocumentsMethod::ReplaceDocuments
+                                        }
+                                        v3::updates::IndexDocumentsMethod::UpdateDocuments => {
+                                            v4::tasks::IndexDocumentsMethod::UpdateDocuments
+                                        }
+                                    },
+                                    primary_key: primary_key.clone(),
+                                    documents_count: 0, // we don't have this info
+                                    allow_index_creation: true, // there was no API-key in the v3
+                                    content_uuid: *content_uuid,
+                                },
+                                v3::Kind::Settings(settings) => {
+                                    v4::tasks::TaskContent::SettingsUpdate {
+                                        settings: v4::Settings::from(settings.clone()),
+                                        is_deletion: false, // that didn't exist at this time
+                                        allow_index_creation: true, // there was no API-key in the v3
+                                    }
+                                }
+                                v3::Kind::ClearDocuments => {
+                                    v4::tasks::TaskContent::DocumentDeletion(
+                                        v4::tasks::DocumentDeletion::Clear,
+                                    )
+                                }
+                            },
+                            events: match task.update {
+                                v3::Status::Processing(processing) => {
+                                    vec![v4::tasks::TaskEvent::Created(processing.from.enqueued_at)]
+                                }
+                                v3::Status::Enqueued(enqueued) => {
+                                    vec![v4::tasks::TaskEvent::Created(enqueued.enqueued_at)]
+                                }
+                                v3::Status::Processed(processed) => {
+                                    vec![
+                                        v4::tasks::TaskEvent::Created(
+                                            processed.from.from.enqueued_at,
+                                        ),
+                                        v4::tasks::TaskEvent::Processing(
+                                            processed.from.started_processing_at,
+                                        ),
+                                        v4::tasks::TaskEvent::Succeded {
+                                            result: match processed.success {
+                                                v3::updates::UpdateResult::DocumentsAddition(
+                                                    document_addition,
+                                                ) => v4::tasks::TaskResult::DocumentAddition {
+                                                    indexed_documents: document_addition
+                                                        .nb_documents
+                                                        as u64,
+                                                },
+                                                v3::updates::UpdateResult::DocumentDeletion {
+                                                    deleted,
+                                                } => v4::tasks::TaskResult::DocumentDeletion {
+                                                    deleted_documents: deleted,
+                                                },
+                                                v3::updates::UpdateResult::Other => {
+                                                    v4::tasks::TaskResult::Other
+                                                }
+                                            },
+                                            timestamp: processed.processed_at,
+                                        },
+                                    ]
+                                }
+                                v3::Status::Failed(failed) => vec![
+                                    v4::tasks::TaskEvent::Created(failed.from.from.enqueued_at),
+                                    v4::tasks::TaskEvent::Processing(
+                                        failed.from.started_processing_at,
+                                    ),
+                                    v4::tasks::TaskEvent::Failed {
+                                        error: v4::ResponseError::from_msg(
+                                            failed.msg.to_string(),
+                                            failed.code.into(),
+                                        ),
+                                        timestamp: failed.failed_at,
+                                    },
+                                ],
+                                v3::Status::Aborted(aborted) => vec![
+                            v4::tasks::TaskEvent::Created(aborted.from.enqueued_at),
+                            v4::tasks::TaskEvent::Failed {
+                                error: v4::ResponseError::from_msg(
+                                    "Task was aborted in a previous version of meilisearch."
+                                        .to_string(),
+                                    v4::errors::Code::UnretrievableErrorCode,
+                                ),
+                                timestamp: aborted.aborted_at,
+                            },
+                        ],
+                            },
+                        };
+
+                        Some((task, content_file))
+                    })
+                })
+                .filter_map(|res| res.transpose()),
+        )
+    }
+
+    pub fn keys(&mut self) -> Box<dyn Iterator<Item = Result<v4::Key>> + '_> {
+        Box::new(std::iter::empty())
+    }
+}
+
+pub enum CompatIndexV3ToV4 {
+    V3(v3::V3IndexReader),
+    Compat(CompatIndexV2ToV3),
+}
+
+impl From<v3::V3IndexReader> for CompatIndexV3ToV4 {
+    fn from(index_reader: v3::V3IndexReader) -> Self {
+        Self::V3(index_reader)
+    }
+}
+
+impl From<CompatIndexV2ToV3> for CompatIndexV3ToV4 {
+    fn from(index_reader: CompatIndexV2ToV3) -> Self {
+        Self::Compat(index_reader)
+    }
+}
+
+impl CompatIndexV3ToV4 {
+    pub fn new(v3: v3::V3IndexReader) -> CompatIndexV3ToV4 {
+        CompatIndexV3ToV4::V3(v3)
+    }
+
+    pub fn metadata(&self) -> &crate::IndexMetadata {
+        match self {
+            CompatIndexV3ToV4::V3(v3) => v3.metadata(),
+            CompatIndexV3ToV4::Compat(compat) => compat.metadata(),
+        }
+    }
+
+    pub fn documents(&mut self) -> Result<Box<dyn Iterator<Item = Result<v4::Document>> + '_>> {
+        match self {
+            CompatIndexV3ToV4::V3(v3) => v3
+                .documents()
+                .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<v4::Document>> + '_>),
+
+            CompatIndexV3ToV4::Compat(compat) => compat
+                .documents()
+                .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<v4::Document>> + '_>),
+        }
+    }
+
+    pub fn settings(&mut self) -> Result<v4::Settings<v4::Checked>> {
+        Ok(match self {
+            CompatIndexV3ToV4::V3(v3) => {
+                v4::Settings::<v4::Unchecked>::from(v3.settings()?).check()
+            }
+            CompatIndexV3ToV4::Compat(compat) => {
+                v4::Settings::<v4::Unchecked>::from(compat.settings()?).check()
+            }
+        })
+    }
+}
+
+impl<T> From<v3::Setting<T>> for v4::Setting<T> {
+    fn from(setting: v3::Setting<T>) -> Self {
+        match setting {
+            v3::Setting::Set(t) => v4::Setting::Set(t),
+            v3::Setting::Reset => v4::Setting::Reset,
+            v3::Setting::NotSet => v4::Setting::NotSet,
+        }
+    }
+}
+
+impl From<v3::Code> for v4::Code {
+    fn from(code: v3::Code) -> Self {
+        match code {
+            v3::Code::CreateIndex => v4::Code::CreateIndex,
+            v3::Code::IndexAlreadyExists => v4::Code::IndexAlreadyExists,
+            v3::Code::IndexNotFound => v4::Code::IndexNotFound,
+            v3::Code::InvalidIndexUid => v4::Code::InvalidIndexUid,
+            v3::Code::InvalidState => v4::Code::InvalidState,
+            v3::Code::MissingPrimaryKey => v4::Code::MissingPrimaryKey,
+            v3::Code::PrimaryKeyAlreadyPresent => v4::Code::PrimaryKeyAlreadyPresent,
+            v3::Code::MaxFieldsLimitExceeded => v4::Code::MaxFieldsLimitExceeded,
+            v3::Code::MissingDocumentId => v4::Code::MissingDocumentId,
+            v3::Code::InvalidDocumentId => v4::Code::InvalidDocumentId,
+            v3::Code::Filter => v4::Code::Filter,
+            v3::Code::Sort => v4::Code::Sort,
+            v3::Code::BadParameter => v4::Code::BadParameter,
+            v3::Code::BadRequest => v4::Code::BadRequest,
+            v3::Code::DatabaseSizeLimitReached => v4::Code::DatabaseSizeLimitReached,
+            v3::Code::DocumentNotFound => v4::Code::DocumentNotFound,
+            v3::Code::Internal => v4::Code::Internal,
+            v3::Code::InvalidGeoField => v4::Code::InvalidGeoField,
+            v3::Code::InvalidRankingRule => v4::Code::InvalidRankingRule,
+            v3::Code::InvalidStore => v4::Code::InvalidStore,
+            v3::Code::InvalidToken => v4::Code::InvalidToken,
+            v3::Code::MissingAuthorizationHeader => v4::Code::MissingAuthorizationHeader,
+            v3::Code::NoSpaceLeftOnDevice => v4::Code::NoSpaceLeftOnDevice,
+            v3::Code::DumpNotFound => v4::Code::DumpNotFound,
+            v3::Code::TaskNotFound => v4::Code::TaskNotFound,
+            v3::Code::PayloadTooLarge => v4::Code::PayloadTooLarge,
+            v3::Code::RetrieveDocument => v4::Code::RetrieveDocument,
+            v3::Code::SearchDocuments => v4::Code::SearchDocuments,
+            v3::Code::UnsupportedMediaType => v4::Code::UnsupportedMediaType,
+            v3::Code::DumpAlreadyInProgress => v4::Code::DumpAlreadyInProgress,
+            v3::Code::DumpProcessFailed => v4::Code::DumpProcessFailed,
+            v3::Code::InvalidContentType => v4::Code::InvalidContentType,
+            v3::Code::MissingContentType => v4::Code::MissingContentType,
+            v3::Code::MalformedPayload => v4::Code::MalformedPayload,
+            v3::Code::MissingPayload => v4::Code::MissingPayload,
+            v3::Code::UnretrievableErrorCode => v4::Code::UnretrievableErrorCode,
+            v3::Code::MalformedDump => v4::Code::MalformedDump,
+        }
+    }
+}
+
+impl<T> From<v3::Settings<T>> for v4::Settings<v4::Unchecked> {
+    fn from(settings: v3::Settings<T>) -> Self {
+        v4::Settings {
+            displayed_attributes: settings.displayed_attributes.into(),
+            searchable_attributes: settings.searchable_attributes.into(),
+            filterable_attributes: settings.filterable_attributes.into(),
+            sortable_attributes: settings.sortable_attributes.into(),
+            ranking_rules: settings.ranking_rules.into(),
+            stop_words: settings.stop_words.into(),
+            synonyms: settings.synonyms.into(),
+            distinct_attribute: settings.distinct_attribute.into(),
+            typo_tolerance: v4::Setting::NotSet,
+            _kind: std::marker::PhantomData,
+        }
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::BufReader;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use tempfile::TempDir;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn compat_v3_v4() {
+        let dump = File::open("tests/assets/v3.dump").unwrap();
+        let dir = TempDir::new().unwrap();
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(dir.path()).unwrap();
+
+        let mut dump = v3::V3Reader::open(dir).unwrap().to_v4();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-07 11:39:03.709153554 +00:00:00");
+
+        // tasks
+        let tasks = dump.tasks().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, mut update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"79bc053583a1a7172bbaaafb1edaeb78");
+        assert_eq!(update_files.len(), 10);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        let update_file = update_files.remove(0).unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(update_file), @"7b8889539b669c7b9ddba448bafa385d");
+
+        // keys
+        let keys = dump.keys().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys, { "[].uid" => "[uuid]" }), @"d751713988987e9331980363e24189ce");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies2 = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"d3402aff19b90acea9e9a07c466690aa");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"548284a84de510f71e88e6cdea495cf5");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"687aaab250f01b55d57bc69aa313b581");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d153b5a81d8b3cdcbe1dec270b574022");
+
+        // movies2
+        insta::assert_json_snapshot!(movies2.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies_2",
+          "primaryKey": null,
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies2.settings()), @"cd9fedbd7e3492831a94da62c90013ea");
+        let documents = movies2.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 0);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d751713988987e9331980363e24189ce");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"cd9fedbd7e3492831a94da62c90013ea");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/compat/v4_to_v5.rs

@@ -0,0 +1,468 @@
+use super::v3_to_v4::{CompatIndexV3ToV4, CompatV3ToV4};
+use super::v5_to_v6::CompatV5ToV6;
+use crate::reader::{v4, v5, Document};
+use crate::Result;
+
+pub enum CompatV4ToV5 {
+    V4(v4::V4Reader),
+    Compat(CompatV3ToV4),
+}
+
+impl CompatV4ToV5 {
+    pub fn new(v4: v4::V4Reader) -> CompatV4ToV5 {
+        CompatV4ToV5::V4(v4)
+    }
+
+    pub fn to_v6(self) -> CompatV5ToV6 {
+        CompatV5ToV6::Compat(self)
+    }
+
+    pub fn version(&self) -> crate::Version {
+        match self {
+            CompatV4ToV5::V4(v4) => v4.version(),
+            CompatV4ToV5::Compat(compat) => compat.version(),
+        }
+    }
+
+    pub fn date(&self) -> Option<time::OffsetDateTime> {
+        match self {
+            CompatV4ToV5::V4(v4) => v4.date(),
+            CompatV4ToV5::Compat(compat) => compat.date(),
+        }
+    }
+
+    pub fn instance_uid(&self) -> Result<Option<uuid::Uuid>> {
+        match self {
+            CompatV4ToV5::V4(v4) => v4.instance_uid(),
+            CompatV4ToV5::Compat(compat) => compat.instance_uid(),
+        }
+    }
+
+    pub fn indexes(&self) -> Result<Box<dyn Iterator<Item = Result<CompatIndexV4ToV5>> + '_>> {
+        Ok(match self {
+            CompatV4ToV5::V4(v4) => {
+                Box::new(v4.indexes()?.map(|index| index.map(CompatIndexV4ToV5::from)))
+                    as Box<dyn Iterator<Item = Result<CompatIndexV4ToV5>> + '_>
+            }
+
+            CompatV4ToV5::Compat(compat) => {
+                Box::new(compat.indexes()?.map(|index| index.map(CompatIndexV4ToV5::from)))
+                    as Box<dyn Iterator<Item = Result<CompatIndexV4ToV5>> + '_>
+            }
+        })
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Box<dyn Iterator<Item = Result<(v5::Task, Option<Box<crate::reader::UpdateFile>>)>> + '_>
+    {
+        let tasks = match self {
+            CompatV4ToV5::V4(v4) => v4.tasks(),
+            CompatV4ToV5::Compat(compat) => compat.tasks(),
+        };
+        Box::new(tasks.map(|task| {
+            task.map(|(task, content_file)| {
+                let task = v5::Task {
+                    id: task.id,
+                    content: match task.content {
+                        v4::tasks::TaskContent::DocumentAddition {
+                            content_uuid,
+                            merge_strategy,
+                            primary_key,
+                            documents_count,
+                            allow_index_creation,
+                        } => v5::tasks::TaskContent::DocumentAddition {
+                            index_uid: v5::meta::IndexUid(task.index_uid.0),
+                            content_uuid,
+                            merge_strategy: match merge_strategy {
+                                v4::tasks::IndexDocumentsMethod::ReplaceDocuments => {
+                                    v5::tasks::IndexDocumentsMethod::ReplaceDocuments
+                                }
+                                v4::tasks::IndexDocumentsMethod::UpdateDocuments => {
+                                    v5::tasks::IndexDocumentsMethod::UpdateDocuments
+                                }
+                            },
+                            primary_key,
+                            documents_count,
+                            allow_index_creation,
+                        },
+                        v4::tasks::TaskContent::DocumentDeletion(deletion) => {
+                            v5::tasks::TaskContent::DocumentDeletion {
+                                index_uid: v5::meta::IndexUid(task.index_uid.0),
+                                deletion: match deletion {
+                                    v4::tasks::DocumentDeletion::Clear => {
+                                        v5::tasks::DocumentDeletion::Clear
+                                    }
+                                    v4::tasks::DocumentDeletion::Ids(ids) => {
+                                        v5::tasks::DocumentDeletion::Ids(ids)
+                                    }
+                                },
+                            }
+                        }
+                        v4::tasks::TaskContent::SettingsUpdate {
+                            settings,
+                            is_deletion,
+                            allow_index_creation,
+                        } => v5::tasks::TaskContent::SettingsUpdate {
+                            index_uid: v5::meta::IndexUid(task.index_uid.0),
+                            settings: settings.into(),
+                            is_deletion,
+                            allow_index_creation,
+                        },
+                        v4::tasks::TaskContent::IndexDeletion => {
+                            v5::tasks::TaskContent::IndexDeletion {
+                                index_uid: v5::meta::IndexUid(task.index_uid.0),
+                            }
+                        }
+                        v4::tasks::TaskContent::IndexCreation { primary_key } => {
+                            v5::tasks::TaskContent::IndexCreation {
+                                index_uid: v5::meta::IndexUid(task.index_uid.0),
+                                primary_key,
+                            }
+                        }
+                        v4::tasks::TaskContent::IndexUpdate { primary_key } => {
+                            v5::tasks::TaskContent::IndexUpdate {
+                                index_uid: v5::meta::IndexUid(task.index_uid.0),
+                                primary_key,
+                            }
+                        }
+                    },
+                    events: task
+                        .events
+                        .into_iter()
+                        .map(|event| match event {
+                            v4::tasks::TaskEvent::Created(date) => {
+                                v5::tasks::TaskEvent::Created(date)
+                            }
+                            v4::tasks::TaskEvent::Batched { timestamp, batch_id } => {
+                                v5::tasks::TaskEvent::Batched { timestamp, batch_id }
+                            }
+                            v4::tasks::TaskEvent::Processing(date) => {
+                                v5::tasks::TaskEvent::Processing(date)
+                            }
+                            v4::tasks::TaskEvent::Succeded { result, timestamp } => {
+                                v5::tasks::TaskEvent::Succeeded {
+                                    result: match result {
+                                        v4::tasks::TaskResult::DocumentAddition {
+                                            indexed_documents,
+                                        } => v5::tasks::TaskResult::DocumentAddition {
+                                            indexed_documents,
+                                        },
+                                        v4::tasks::TaskResult::DocumentDeletion {
+                                            deleted_documents,
+                                        } => v5::tasks::TaskResult::DocumentDeletion {
+                                            deleted_documents,
+                                        },
+                                        v4::tasks::TaskResult::ClearAll { deleted_documents } => {
+                                            v5::tasks::TaskResult::ClearAll { deleted_documents }
+                                        }
+                                        v4::tasks::TaskResult::Other => {
+                                            v5::tasks::TaskResult::Other
+                                        }
+                                    },
+                                    timestamp,
+                                }
+                            }
+                            v4::tasks::TaskEvent::Failed { error, timestamp } => {
+                                v5::tasks::TaskEvent::Failed {
+                                    error: v5::ResponseError::from(error),
+                                    timestamp,
+                                }
+                            }
+                        })
+                        .collect(),
+                };
+
+                (task, content_file)
+            })
+        }))
+    }
+
+    pub fn keys(&mut self) -> Box<dyn Iterator<Item = Result<v5::Key>> + '_> {
+        let keys = match self {
+            CompatV4ToV5::V4(v4) => v4.keys(),
+            CompatV4ToV5::Compat(compat) => compat.keys(),
+        };
+        Box::new(keys.map(|key| {
+            key.map(|key| v5::Key {
+                description: key.description,
+                name: None,
+                uid: v5::keys::KeyId::new_v4(),
+                actions: key.actions.into_iter().filter_map(|action| action.into()).collect(),
+                indexes: key
+                    .indexes
+                    .into_iter()
+                    .map(|index| match index.as_str() {
+                        "*" => v5::StarOr::Star,
+                        _ => v5::StarOr::Other(v5::meta::IndexUid(index)),
+                    })
+                    .collect(),
+                expires_at: key.expires_at,
+                created_at: key.created_at,
+                updated_at: key.updated_at,
+            })
+        }))
+    }
+}
+
+pub enum CompatIndexV4ToV5 {
+    V4(v4::V4IndexReader),
+    Compat(CompatIndexV3ToV4),
+}
+
+impl From<v4::V4IndexReader> for CompatIndexV4ToV5 {
+    fn from(index_reader: v4::V4IndexReader) -> Self {
+        Self::V4(index_reader)
+    }
+}
+
+impl From<CompatIndexV3ToV4> for CompatIndexV4ToV5 {
+    fn from(index_reader: CompatIndexV3ToV4) -> Self {
+        Self::Compat(index_reader)
+    }
+}
+
+impl CompatIndexV4ToV5 {
+    pub fn metadata(&self) -> &crate::IndexMetadata {
+        match self {
+            CompatIndexV4ToV5::V4(v4) => v4.metadata(),
+            CompatIndexV4ToV5::Compat(compat) => compat.metadata(),
+        }
+    }
+
+    pub fn documents(&mut self) -> Result<Box<dyn Iterator<Item = Result<Document>> + '_>> {
+        match self {
+            CompatIndexV4ToV5::V4(v4) => v4
+                .documents()
+                .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<Document>> + '_>),
+            CompatIndexV4ToV5::Compat(compat) => compat
+                .documents()
+                .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<Document>> + '_>),
+        }
+    }
+
+    pub fn settings(&mut self) -> Result<v5::Settings<v5::Checked>> {
+        match self {
+            CompatIndexV4ToV5::V4(v4) => Ok(v5::Settings::from(v4.settings()?).check()),
+            CompatIndexV4ToV5::Compat(compat) => Ok(v5::Settings::from(compat.settings()?).check()),
+        }
+    }
+}
+
+impl<T> From<v4::Setting<T>> for v5::Setting<T> {
+    fn from(setting: v4::Setting<T>) -> Self {
+        match setting {
+            v4::Setting::Set(t) => v5::Setting::Set(t),
+            v4::Setting::Reset => v5::Setting::Reset,
+            v4::Setting::NotSet => v5::Setting::NotSet,
+        }
+    }
+}
+
+impl From<v4::ResponseError> for v5::ResponseError {
+    fn from(error: v4::ResponseError) -> Self {
+        let code = match error.error_code.as_ref() {
+            "index_creation_failed" => v5::Code::CreateIndex,
+            "index_already_exists" => v5::Code::IndexAlreadyExists,
+            "index_not_found" => v5::Code::IndexNotFound,
+            "invalid_index_uid" => v5::Code::InvalidIndexUid,
+            "invalid_min_word_length_for_typo" => v5::Code::InvalidMinWordLengthForTypo,
+            "invalid_state" => v5::Code::InvalidState,
+            "primary_key_inference_failed" => v5::Code::MissingPrimaryKey,
+            "index_primary_key_already_exists" => v5::Code::PrimaryKeyAlreadyPresent,
+            "max_fields_limit_exceeded" => v5::Code::MaxFieldsLimitExceeded,
+            "missing_document_id" => v5::Code::MissingDocumentId,
+            "invalid_document_id" => v5::Code::InvalidDocumentId,
+            "invalid_filter" => v5::Code::Filter,
+            "invalid_sort" => v5::Code::Sort,
+            "bad_parameter" => v5::Code::BadParameter,
+            "bad_request" => v5::Code::BadRequest,
+            "database_size_limit_reached" => v5::Code::DatabaseSizeLimitReached,
+            "document_not_found" => v5::Code::DocumentNotFound,
+            "internal" => v5::Code::Internal,
+            "invalid_geo_field" => v5::Code::InvalidGeoField,
+            "invalid_ranking_rule" => v5::Code::InvalidRankingRule,
+            "invalid_store_file" => v5::Code::InvalidStore,
+            "invalid_api_key" => v5::Code::InvalidToken,
+            "missing_authorization_header" => v5::Code::MissingAuthorizationHeader,
+            "no_space_left_on_device" => v5::Code::NoSpaceLeftOnDevice,
+            "dump_not_found" => v5::Code::DumpNotFound,
+            "task_not_found" => v5::Code::TaskNotFound,
+            "payload_too_large" => v5::Code::PayloadTooLarge,
+            "unretrievable_document" => v5::Code::RetrieveDocument,
+            "search_error" => v5::Code::SearchDocuments,
+            "unsupported_media_type" => v5::Code::UnsupportedMediaType,
+            "dump_already_processing" => v5::Code::DumpAlreadyInProgress,
+            "dump_process_failed" => v5::Code::DumpProcessFailed,
+            "invalid_content_type" => v5::Code::InvalidContentType,
+            "missing_content_type" => v5::Code::MissingContentType,
+            "malformed_payload" => v5::Code::MalformedPayload,
+            "missing_payload" => v5::Code::MissingPayload,
+            "api_key_not_found" => v5::Code::ApiKeyNotFound,
+            "missing_parameter" => v5::Code::MissingParameter,
+            "invalid_api_key_actions" => v5::Code::InvalidApiKeyActions,
+            "invalid_api_key_indexes" => v5::Code::InvalidApiKeyIndexes,
+            "invalid_api_key_expires_at" => v5::Code::InvalidApiKeyExpiresAt,
+            "invalid_api_key_description" => v5::Code::InvalidApiKeyDescription,
+            other => {
+                log::warn!("Unknown error code {}", other);
+                v5::Code::UnretrievableErrorCode
+            }
+        };
+        v5::ResponseError::from_msg(error.message, code)
+    }
+}
+
+impl<T> From<v4::Settings<T>> for v5::Settings<v5::Unchecked> {
+    fn from(settings: v4::Settings<T>) -> Self {
+        v5::Settings {
+            displayed_attributes: settings.displayed_attributes.into(),
+            searchable_attributes: settings.searchable_attributes.into(),
+            filterable_attributes: settings.filterable_attributes.into(),
+            sortable_attributes: settings.sortable_attributes.into(),
+            ranking_rules: settings.ranking_rules.into(),
+            stop_words: settings.stop_words.into(),
+            synonyms: settings.synonyms.into(),
+            distinct_attribute: settings.distinct_attribute.into(),
+            typo_tolerance: match settings.typo_tolerance {
+                v4::Setting::Set(typo) => v5::Setting::Set(v5::TypoTolerance {
+                    enabled: typo.enabled.into(),
+                    min_word_size_for_typos: match typo.min_word_size_for_typos {
+                        v4::Setting::Set(t) => v5::Setting::Set(v5::MinWordSizeForTypos {
+                            one_typo: t.one_typo.into(),
+                            two_typos: t.two_typos.into(),
+                        }),
+                        v4::Setting::Reset => v5::Setting::Reset,
+                        v4::Setting::NotSet => v5::Setting::NotSet,
+                    },
+                    disable_on_words: typo.disable_on_words.into(),
+                    disable_on_attributes: typo.disable_on_attributes.into(),
+                }),
+                v4::Setting::Reset => v5::Setting::Reset,
+                v4::Setting::NotSet => v5::Setting::NotSet,
+            },
+            faceting: v5::Setting::NotSet,
+            pagination: v5::Setting::NotSet,
+            _kind: std::marker::PhantomData,
+        }
+    }
+}
+
+impl From<v4::Action> for Option<v5::Action> {
+    fn from(key: v4::Action) -> Self {
+        match key {
+            v4::Action::All => Some(v5::Action::All),
+            v4::Action::Search => Some(v5::Action::Search),
+            v4::Action::DocumentsAdd => Some(v5::Action::DocumentsAdd),
+            v4::Action::DocumentsGet => Some(v5::Action::DocumentsGet),
+            v4::Action::DocumentsDelete => Some(v5::Action::DocumentsDelete),
+            v4::Action::IndexesAdd => Some(v5::Action::IndexesAdd),
+            v4::Action::IndexesGet => Some(v5::Action::IndexesGet),
+            v4::Action::IndexesUpdate => Some(v5::Action::IndexesUpdate),
+            v4::Action::IndexesDelete => Some(v5::Action::IndexesDelete),
+            v4::Action::TasksGet => Some(v5::Action::TasksGet),
+            v4::Action::SettingsGet => Some(v5::Action::SettingsGet),
+            v4::Action::SettingsUpdate => Some(v5::Action::SettingsUpdate),
+            v4::Action::StatsGet => Some(v5::Action::StatsGet),
+            v4::Action::DumpsCreate => Some(v5::Action::DumpsCreate),
+            v4::Action::DumpsGet => None,
+            v4::Action::Version => Some(v5::Action::Version),
+        }
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::BufReader;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use tempfile::TempDir;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn compat_v4_v5() {
+        let dump = File::open("tests/assets/v4.dump").unwrap();
+        let dir = TempDir::new().unwrap();
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(dir.path()).unwrap();
+
+        let mut dump = v4::V4Reader::open(dir).unwrap().to_v5();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-06 12:53:49.131989609 +00:00:00");
+        insta::assert_display_snapshot!(dump.instance_uid().unwrap().unwrap(), @"9e15e977-f2ae-4761-943f-1eaf75fd736d");
+
+        // tasks
+        let tasks = dump.tasks().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"ed9a30cded4c046ef46f7cff7450347e");
+        assert_eq!(update_files.len(), 10);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        // keys
+        let keys = dump.keys().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys, { "[].uid" => "[uuid]" }), @"1384361d734fd77c23804c9696228660");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"26947283836ee4cdf0974f82efcc5332");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"b01c8371aea4c7171af0d4d846a2bdca");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"156871410d17e23803d0c90ddc6a66cb");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"786022a66ecb992c8a2a60fee070a5ab");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"69c9916142612cf4a2da9b9ed9455e9e");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/compat/v5_to_v6.rs

@@ -0,0 +1,487 @@
+use super::v4_to_v5::{CompatIndexV4ToV5, CompatV4ToV5};
+use crate::reader::{v5, v6, Document, UpdateFile};
+use crate::Result;
+
+pub enum CompatV5ToV6 {
+    V5(v5::V5Reader),
+    Compat(CompatV4ToV5),
+}
+
+impl CompatV5ToV6 {
+    pub fn new_v5(v5: v5::V5Reader) -> CompatV5ToV6 {
+        CompatV5ToV6::V5(v5)
+    }
+
+    pub fn version(&self) -> crate::Version {
+        match self {
+            CompatV5ToV6::V5(v5) => v5.version(),
+            CompatV5ToV6::Compat(compat) => compat.version(),
+        }
+    }
+
+    pub fn date(&self) -> Option<time::OffsetDateTime> {
+        match self {
+            CompatV5ToV6::V5(v5) => v5.date(),
+            CompatV5ToV6::Compat(compat) => compat.date(),
+        }
+    }
+
+    pub fn instance_uid(&self) -> Result<Option<uuid::Uuid>> {
+        match self {
+            CompatV5ToV6::V5(v5) => v5.instance_uid(),
+            CompatV5ToV6::Compat(compat) => compat.instance_uid(),
+        }
+    }
+
+    pub fn indexes(&self) -> Result<Box<dyn Iterator<Item = Result<CompatIndexV5ToV6>> + '_>> {
+        let indexes = match self {
+            CompatV5ToV6::V5(v5) => {
+                Box::new(v5.indexes()?.map(|index| index.map(CompatIndexV5ToV6::from)))
+                    as Box<dyn Iterator<Item = Result<CompatIndexV5ToV6>> + '_>
+            }
+
+            CompatV5ToV6::Compat(compat) => {
+                Box::new(compat.indexes()?.map(|index| index.map(CompatIndexV5ToV6::from)))
+                    as Box<dyn Iterator<Item = Result<CompatIndexV5ToV6>> + '_>
+            }
+        };
+        Ok(indexes)
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Result<Box<dyn Iterator<Item = Result<(v6::Task, Option<Box<UpdateFile>>)>> + '_>> {
+        let instance_uid = self.instance_uid().ok().flatten();
+        let keys = self.keys()?.collect::<Result<Vec<_>>>()?;
+
+        let tasks = match self {
+            CompatV5ToV6::V5(v5) => v5.tasks(),
+            CompatV5ToV6::Compat(compat) => compat.tasks(),
+        };
+        Ok(Box::new(tasks.map(move |task| {
+            task.map(|(task, content_file)| {
+                let mut task_view: v5::tasks::TaskView = task.clone().into();
+
+                if task_view.status == v5::Status::Processing {
+                    task_view.started_at = None;
+                }
+
+                let task = v6::Task {
+                    uid: task_view.uid,
+                    index_uid: task_view.index_uid,
+                    status: match task_view.status {
+                        v5::Status::Enqueued => v6::Status::Enqueued,
+                        v5::Status::Processing => v6::Status::Enqueued,
+                        v5::Status::Succeeded => v6::Status::Succeeded,
+                        v5::Status::Failed => v6::Status::Failed,
+                    },
+                    kind: match task.content {
+                        v5::tasks::TaskContent::IndexCreation { primary_key, .. } => {
+                            v6::Kind::IndexCreation { primary_key }
+                        }
+                        v5::tasks::TaskContent::IndexUpdate { primary_key, .. } => {
+                            v6::Kind::IndexUpdate { primary_key }
+                        }
+                        v5::tasks::TaskContent::IndexDeletion { .. } => v6::Kind::IndexDeletion,
+                        v5::tasks::TaskContent::DocumentAddition {
+                            merge_strategy,
+                            allow_index_creation,
+                            primary_key,
+                            documents_count,
+                            ..
+                        } => v6::Kind::DocumentImport {
+                            primary_key,
+                            documents_count: documents_count as u64,
+                            method: match merge_strategy {
+                                v5::tasks::IndexDocumentsMethod::ReplaceDocuments => {
+                                    v6::milli::update::IndexDocumentsMethod::ReplaceDocuments
+                                }
+                                v5::tasks::IndexDocumentsMethod::UpdateDocuments => {
+                                    v6::milli::update::IndexDocumentsMethod::UpdateDocuments
+                                }
+                            },
+                            allow_index_creation,
+                        },
+                        v5::tasks::TaskContent::DocumentDeletion { deletion, .. } => match deletion
+                        {
+                            v5::tasks::DocumentDeletion::Clear => v6::Kind::DocumentClear,
+                            v5::tasks::DocumentDeletion::Ids(documents_ids) => {
+                                v6::Kind::DocumentDeletion { documents_ids }
+                            }
+                        },
+                        v5::tasks::TaskContent::SettingsUpdate {
+                            allow_index_creation,
+                            is_deletion,
+                            settings,
+                            ..
+                        } => v6::Kind::Settings {
+                            is_deletion,
+                            allow_index_creation,
+                            settings: Box::new(settings.into()),
+                        },
+                        v5::tasks::TaskContent::Dump { uid } => v6::Kind::DumpCreation {
+                            dump_uid: uid,
+                            keys: keys.clone(),
+                            instance_uid,
+                        },
+                    },
+                    canceled_by: None,
+                    details: task_view.details.map(|details| match details {
+                        v5::Details::DocumentAddition { received_documents, indexed_documents } => {
+                            v6::Details::DocumentAdditionOrUpdate {
+                                received_documents: received_documents as u64,
+                                indexed_documents,
+                            }
+                        }
+                        v5::Details::Settings { settings } => {
+                            v6::Details::SettingsUpdate { settings: Box::new(settings.into()) }
+                        }
+                        v5::Details::IndexInfo { primary_key } => {
+                            v6::Details::IndexInfo { primary_key }
+                        }
+                        v5::Details::DocumentDeletion {
+                            received_document_ids,
+                            deleted_documents,
+                        } => v6::Details::DocumentDeletion {
+                            matched_documents: received_document_ids,
+                            deleted_documents,
+                        },
+                        v5::Details::ClearAll { deleted_documents } => {
+                            v6::Details::ClearAll { deleted_documents }
+                        }
+                        v5::Details::Dump { dump_uid } => v6::Details::Dump { dump_uid },
+                    }),
+                    error: task_view.error.map(|e| e.into()),
+                    enqueued_at: task_view.enqueued_at,
+                    started_at: task_view.started_at,
+                    finished_at: task_view.finished_at,
+                };
+
+                (task, content_file)
+            })
+        })))
+    }
+
+    pub fn keys(&mut self) -> Result<Box<dyn Iterator<Item = Result<v6::Key>> + '_>> {
+        let keys = match self {
+            CompatV5ToV6::V5(v5) => v5.keys()?,
+            CompatV5ToV6::Compat(compat) => compat.keys(),
+        };
+
+        Ok(Box::new(keys.map(|key| {
+            key.map(|key| v6::Key {
+                description: key.description,
+                name: key.name,
+                uid: key.uid,
+                actions: key.actions.into_iter().map(|action| action.into()).collect(),
+                indexes: key
+                    .indexes
+                    .into_iter()
+                    .map(|index| match index {
+                        v5::StarOr::Star => v6::StarOr::Star,
+                        v5::StarOr::Other(uid) => {
+                            v6::StarOr::Other(v6::IndexUid::new_unchecked(uid.as_str()))
+                        }
+                    })
+                    .collect(),
+                expires_at: key.expires_at,
+                created_at: key.created_at,
+                updated_at: key.updated_at,
+            })
+        })))
+    }
+}
+
+pub enum CompatIndexV5ToV6 {
+    V5(v5::V5IndexReader),
+    Compat(CompatIndexV4ToV5),
+}
+
+impl From<v5::V5IndexReader> for CompatIndexV5ToV6 {
+    fn from(index_reader: v5::V5IndexReader) -> Self {
+        Self::V5(index_reader)
+    }
+}
+
+impl From<CompatIndexV4ToV5> for CompatIndexV5ToV6 {
+    fn from(index_reader: CompatIndexV4ToV5) -> Self {
+        Self::Compat(index_reader)
+    }
+}
+
+impl CompatIndexV5ToV6 {
+    pub fn new_v5(v5: v5::V5IndexReader) -> CompatIndexV5ToV6 {
+        CompatIndexV5ToV6::V5(v5)
+    }
+
+    pub fn metadata(&self) -> &crate::IndexMetadata {
+        match self {
+            CompatIndexV5ToV6::V5(v5) => v5.metadata(),
+            CompatIndexV5ToV6::Compat(compat) => compat.metadata(),
+        }
+    }
+
+    pub fn documents(&mut self) -> Result<Box<dyn Iterator<Item = Result<Document>> + '_>> {
+        match self {
+            CompatIndexV5ToV6::V5(v5) => v5
+                .documents()
+                .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<Document>> + '_>),
+            CompatIndexV5ToV6::Compat(compat) => compat
+                .documents()
+                .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<Document>> + '_>),
+        }
+    }
+
+    pub fn settings(&mut self) -> Result<v6::Settings<v6::Checked>> {
+        match self {
+            CompatIndexV5ToV6::V5(v5) => Ok(v6::Settings::from(v5.settings()?).check()),
+            CompatIndexV5ToV6::Compat(compat) => Ok(v6::Settings::from(compat.settings()?).check()),
+        }
+    }
+}
+
+impl<T> From<v5::Setting<T>> for v6::Setting<T> {
+    fn from(setting: v5::Setting<T>) -> Self {
+        match setting {
+            v5::Setting::Set(t) => v6::Setting::Set(t),
+            v5::Setting::Reset => v6::Setting::Reset,
+            v5::Setting::NotSet => v6::Setting::NotSet,
+        }
+    }
+}
+
+impl From<v5::ResponseError> for v6::ResponseError {
+    fn from(error: v5::ResponseError) -> Self {
+        let code = match error.error_code.as_ref() {
+            "index_creation_failed" => v6::Code::CreateIndex,
+            "index_already_exists" => v6::Code::IndexAlreadyExists,
+            "index_not_found" => v6::Code::IndexNotFound,
+            "invalid_index_uid" => v6::Code::InvalidIndexUid,
+            "invalid_min_word_length_for_typo" => v6::Code::InvalidMinWordLengthForTypo,
+            "invalid_state" => v6::Code::InvalidState,
+            "primary_key_inference_failed" => v6::Code::MissingPrimaryKey,
+            "index_primary_key_already_exists" => v6::Code::PrimaryKeyAlreadyPresent,
+            "max_fields_limit_exceeded" => v6::Code::MaxFieldsLimitExceeded,
+            "missing_document_id" => v6::Code::MissingDocumentId,
+            "invalid_document_id" => v6::Code::InvalidDocumentId,
+            "invalid_filter" => v6::Code::Filter,
+            "invalid_sort" => v6::Code::Sort,
+            "bad_parameter" => v6::Code::BadParameter,
+            "bad_request" => v6::Code::BadRequest,
+            "database_size_limit_reached" => v6::Code::DatabaseSizeLimitReached,
+            "document_not_found" => v6::Code::DocumentNotFound,
+            "internal" => v6::Code::Internal,
+            "invalid_geo_field" => v6::Code::InvalidGeoField,
+            "invalid_ranking_rule" => v6::Code::InvalidRankingRule,
+            "invalid_store_file" => v6::Code::InvalidStore,
+            "invalid_api_key" => v6::Code::InvalidToken,
+            "missing_authorization_header" => v6::Code::MissingAuthorizationHeader,
+            "no_space_left_on_device" => v6::Code::NoSpaceLeftOnDevice,
+            "dump_not_found" => v6::Code::DumpNotFound,
+            "task_not_found" => v6::Code::TaskNotFound,
+            "payload_too_large" => v6::Code::PayloadTooLarge,
+            "unretrievable_document" => v6::Code::RetrieveDocument,
+            "search_error" => v6::Code::SearchDocuments,
+            "unsupported_media_type" => v6::Code::UnsupportedMediaType,
+            "dump_already_processing" => v6::Code::DumpAlreadyInProgress,
+            "dump_process_failed" => v6::Code::DumpProcessFailed,
+            "invalid_content_type" => v6::Code::InvalidContentType,
+            "missing_content_type" => v6::Code::MissingContentType,
+            "malformed_payload" => v6::Code::MalformedPayload,
+            "missing_payload" => v6::Code::MissingPayload,
+            "api_key_not_found" => v6::Code::ApiKeyNotFound,
+            "missing_parameter" => v6::Code::MissingParameter,
+            "invalid_api_key_actions" => v6::Code::InvalidApiKeyActions,
+            "invalid_api_key_indexes" => v6::Code::InvalidApiKeyIndexes,
+            "invalid_api_key_expires_at" => v6::Code::InvalidApiKeyExpiresAt,
+            "invalid_api_key_description" => v6::Code::InvalidApiKeyDescription,
+            "invalid_api_key_name" => v6::Code::InvalidApiKeyName,
+            "invalid_api_key_uid" => v6::Code::InvalidApiKeyUid,
+            "immutable_field" => v6::Code::ImmutableField,
+            "api_key_already_exists" => v6::Code::ApiKeyAlreadyExists,
+            other => {
+                log::warn!("Unknown error code {}", other);
+                v6::Code::UnretrievableErrorCode
+            }
+        };
+        v6::ResponseError::from_msg(error.message, code)
+    }
+}
+
+impl<T> From<v5::Settings<T>> for v6::Settings<v6::Unchecked> {
+    fn from(settings: v5::Settings<T>) -> Self {
+        v6::Settings {
+            displayed_attributes: settings.displayed_attributes.into(),
+            searchable_attributes: settings.searchable_attributes.into(),
+            filterable_attributes: settings.filterable_attributes.into(),
+            sortable_attributes: settings.sortable_attributes.into(),
+            ranking_rules: settings.ranking_rules.into(),
+            stop_words: settings.stop_words.into(),
+            synonyms: settings.synonyms.into(),
+            distinct_attribute: settings.distinct_attribute.into(),
+            typo_tolerance: match settings.typo_tolerance {
+                v5::Setting::Set(typo) => v6::Setting::Set(v6::TypoTolerance {
+                    enabled: typo.enabled.into(),
+                    min_word_size_for_typos: match typo.min_word_size_for_typos {
+                        v5::Setting::Set(t) => v6::Setting::Set(v6::MinWordSizeForTypos {
+                            one_typo: t.one_typo.into(),
+                            two_typos: t.two_typos.into(),
+                        }),
+                        v5::Setting::Reset => v6::Setting::Reset,
+                        v5::Setting::NotSet => v6::Setting::NotSet,
+                    },
+                    disable_on_words: typo.disable_on_words.into(),
+                    disable_on_attributes: typo.disable_on_attributes.into(),
+                }),
+                v5::Setting::Reset => v6::Setting::Reset,
+                v5::Setting::NotSet => v6::Setting::NotSet,
+            },
+            faceting: match settings.faceting {
+                v5::Setting::Set(faceting) => v6::Setting::Set(v6::FacetingSettings {
+                    max_values_per_facet: faceting.max_values_per_facet.into(),
+                }),
+                v5::Setting::Reset => v6::Setting::Reset,
+                v5::Setting::NotSet => v6::Setting::NotSet,
+            },
+            pagination: match settings.pagination {
+                v5::Setting::Set(pagination) => v6::Setting::Set(v6::PaginationSettings {
+                    max_total_hits: pagination.max_total_hits.into(),
+                }),
+                v5::Setting::Reset => v6::Setting::Reset,
+                v5::Setting::NotSet => v6::Setting::NotSet,
+            },
+            _kind: std::marker::PhantomData,
+        }
+    }
+}
+
+impl From<v5::Action> for v6::Action {
+    fn from(key: v5::Action) -> Self {
+        match key {
+            v5::Action::All => v6::Action::All,
+            v5::Action::Search => v6::Action::Search,
+            v5::Action::DocumentsAll => v6::Action::DocumentsAll,
+            v5::Action::DocumentsAdd => v6::Action::DocumentsAdd,
+            v5::Action::DocumentsGet => v6::Action::DocumentsGet,
+            v5::Action::DocumentsDelete => v6::Action::DocumentsDelete,
+            v5::Action::IndexesAll => v6::Action::IndexesAll,
+            v5::Action::IndexesAdd => v6::Action::IndexesAdd,
+            v5::Action::IndexesGet => v6::Action::IndexesGet,
+            v5::Action::IndexesUpdate => v6::Action::IndexesUpdate,
+            v5::Action::IndexesDelete => v6::Action::IndexesDelete,
+            v5::Action::TasksAll => v6::Action::TasksAll,
+            v5::Action::TasksGet => v6::Action::TasksGet,
+            v5::Action::SettingsAll => v6::Action::SettingsAll,
+            v5::Action::SettingsGet => v6::Action::SettingsGet,
+            v5::Action::SettingsUpdate => v6::Action::SettingsUpdate,
+            v5::Action::StatsAll => v6::Action::StatsAll,
+            v5::Action::StatsGet => v6::Action::StatsGet,
+            v5::Action::MetricsAll => v6::Action::MetricsAll,
+            v5::Action::MetricsGet => v6::Action::MetricsGet,
+            v5::Action::DumpsAll => v6::Action::DumpsAll,
+            v5::Action::DumpsCreate => v6::Action::DumpsCreate,
+            v5::Action::Version => v6::Action::Version,
+            v5::Action::KeysAdd => v6::Action::KeysAdd,
+            v5::Action::KeysGet => v6::Action::KeysGet,
+            v5::Action::KeysUpdate => v6::Action::KeysUpdate,
+            v5::Action::KeysDelete => v6::Action::KeysDelete,
+        }
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::BufReader;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use tempfile::TempDir;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn compat_v5_v6() {
+        let dump = File::open("tests/assets/v5.dump").unwrap();
+        let dir = TempDir::new().unwrap();
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(dir.path()).unwrap();
+
+        let mut dump = v5::V5Reader::open(dir).unwrap().to_v6();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-04 15:55:10.344982459 +00:00:00");
+        insta::assert_display_snapshot!(dump.instance_uid().unwrap().unwrap(), @"9e15e977-f2ae-4761-943f-1eaf75fd736d");
+
+        // tasks
+        let tasks = dump.tasks().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"42d4200cf6d92a6449989ca48cd8e28a");
+        assert_eq!(update_files.len(), 22);
+        assert!(update_files[0].is_none()); // the dump creation
+        assert!(update_files[1].is_some()); // the enqueued document addition
+        assert!(update_files[2..].iter().all(|u| u.is_none())); // everything already processed
+
+        // keys
+        let keys = dump.keys().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys), @"c9d2b467fe2fca0b35580d8a999808fb");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"8e5cadabf74aebe1160bf51c3d489efe");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"b01c8371aea4c7171af0d4d846a2bdca");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"4894ac1e74b9e1069ed5ee262b7a1aca");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 200);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"e962baafd2fbae4cdd14e876053b0c5a");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"054dbf08a79e08bb9becba6f5d090f13");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/mod.rs

@@ -0,0 +1,535 @@
+use std::fs::File;
+use std::io::{BufReader, Read};
+
+use flate2::bufread::GzDecoder;
+use serde::Deserialize;
+use tempfile::TempDir;
+
+use self::compat::v4_to_v5::CompatV4ToV5;
+use self::compat::v5_to_v6::{CompatIndexV5ToV6, CompatV5ToV6};
+use self::v5::V5Reader;
+use self::v6::{V6IndexReader, V6Reader};
+use crate::{Error, Result, Version};
+
+mod compat;
+
+// pub(self) mod v1;
+pub(self) mod v2;
+pub(self) mod v3;
+pub(self) mod v4;
+pub(self) mod v5;
+pub(self) mod v6;
+
+pub type Document = serde_json::Map<String, serde_json::Value>;
+pub type UpdateFile = dyn Iterator<Item = Result<Document>>;
+
+pub enum DumpReader {
+    Current(V6Reader),
+    Compat(CompatV5ToV6),
+}
+
+impl DumpReader {
+    pub fn open(dump: impl Read) -> Result<DumpReader> {
+        let path = TempDir::new()?;
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(path.path())?;
+
+        #[derive(Deserialize)]
+        #[serde(rename_all = "camelCase")]
+        struct MetadataVersion {
+            pub dump_version: Version,
+        }
+        let mut meta_file = File::open(path.path().join("metadata.json"))?;
+        let MetadataVersion { dump_version } = serde_json::from_reader(&mut meta_file)?;
+
+        match dump_version {
+            // Version::V1 => Ok(Box::new(v1::Reader::open(path)?)),
+            Version::V1 => Err(Error::DumpV1Unsupported),
+            Version::V2 => Ok(v2::V2Reader::open(path)?.to_v3().to_v4().to_v5().to_v6().into()),
+            Version::V3 => Ok(v3::V3Reader::open(path)?.to_v4().to_v5().to_v6().into()),
+            Version::V4 => Ok(v4::V4Reader::open(path)?.to_v5().to_v6().into()),
+            Version::V5 => Ok(v5::V5Reader::open(path)?.to_v6().into()),
+            Version::V6 => Ok(v6::V6Reader::open(path)?.into()),
+        }
+    }
+
+    pub fn version(&self) -> crate::Version {
+        match self {
+            DumpReader::Current(current) => current.version(),
+            DumpReader::Compat(compat) => compat.version(),
+        }
+    }
+
+    pub fn date(&self) -> Option<time::OffsetDateTime> {
+        match self {
+            DumpReader::Current(current) => current.date(),
+            DumpReader::Compat(compat) => compat.date(),
+        }
+    }
+
+    pub fn instance_uid(&self) -> Result<Option<uuid::Uuid>> {
+        match self {
+            DumpReader::Current(current) => current.instance_uid(),
+            DumpReader::Compat(compat) => compat.instance_uid(),
+        }
+    }
+
+    pub fn indexes(&self) -> Result<Box<dyn Iterator<Item = Result<DumpIndexReader>> + '_>> {
+        match self {
+            DumpReader::Current(current) => {
+                let indexes = Box::new(current.indexes()?.map(|res| res.map(DumpIndexReader::from)))
+                    as Box<dyn Iterator<Item = Result<DumpIndexReader>> + '_>;
+                Ok(indexes)
+            }
+            DumpReader::Compat(compat) => {
+                let indexes = Box::new(compat.indexes()?.map(|res| res.map(DumpIndexReader::from)))
+                    as Box<dyn Iterator<Item = Result<DumpIndexReader>> + '_>;
+                Ok(indexes)
+            }
+        }
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Result<Box<dyn Iterator<Item = Result<(v6::Task, Option<Box<UpdateFile>>)>> + '_>> {
+        match self {
+            DumpReader::Current(current) => Ok(current.tasks()),
+            DumpReader::Compat(compat) => compat.tasks(),
+        }
+    }
+
+    pub fn keys(&mut self) -> Result<Box<dyn Iterator<Item = Result<v6::Key>> + '_>> {
+        match self {
+            DumpReader::Current(current) => Ok(current.keys()),
+            DumpReader::Compat(compat) => compat.keys(),
+        }
+    }
+}
+
+impl From<V6Reader> for DumpReader {
+    fn from(value: V6Reader) -> Self {
+        DumpReader::Current(value)
+    }
+}
+
+impl From<CompatV5ToV6> for DumpReader {
+    fn from(value: CompatV5ToV6) -> Self {
+        DumpReader::Compat(value)
+    }
+}
+
+impl From<V5Reader> for DumpReader {
+    fn from(value: V5Reader) -> Self {
+        DumpReader::Compat(value.to_v6())
+    }
+}
+
+impl From<CompatV4ToV5> for DumpReader {
+    fn from(value: CompatV4ToV5) -> Self {
+        DumpReader::Compat(value.to_v6())
+    }
+}
+
+pub enum DumpIndexReader {
+    Current(v6::V6IndexReader),
+    Compat(Box<CompatIndexV5ToV6>),
+}
+
+impl DumpIndexReader {
+    pub fn new_v6(v6: v6::V6IndexReader) -> DumpIndexReader {
+        DumpIndexReader::Current(v6)
+    }
+
+    pub fn metadata(&self) -> &crate::IndexMetadata {
+        match self {
+            DumpIndexReader::Current(v6) => v6.metadata(),
+            DumpIndexReader::Compat(compat) => compat.metadata(),
+        }
+    }
+
+    pub fn documents(&mut self) -> Result<Box<dyn Iterator<Item = Result<Document>> + '_>> {
+        match self {
+            DumpIndexReader::Current(v6) => v6
+                .documents()
+                .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<Document>> + '_>),
+            DumpIndexReader::Compat(compat) => compat
+                .documents()
+                .map(|iter| Box::new(iter) as Box<dyn Iterator<Item = Result<Document>> + '_>),
+        }
+    }
+
+    pub fn settings(&mut self) -> Result<v6::Settings<v6::Checked>> {
+        match self {
+            DumpIndexReader::Current(v6) => v6.settings(),
+            DumpIndexReader::Compat(compat) => compat.settings(),
+        }
+    }
+}
+
+impl From<V6IndexReader> for DumpIndexReader {
+    fn from(value: V6IndexReader) -> Self {
+        DumpIndexReader::Current(value)
+    }
+}
+
+impl From<CompatIndexV5ToV6> for DumpIndexReader {
+    fn from(value: CompatIndexV5ToV6) -> Self {
+        DumpIndexReader::Compat(Box::new(value))
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+
+    use meili_snap::insta;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn import_dump_v5() {
+        let dump = File::open("tests/assets/v5.dump").unwrap();
+        let mut dump = DumpReader::open(dump).unwrap();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-04 15:55:10.344982459 +00:00:00");
+        insta::assert_display_snapshot!(dump.instance_uid().unwrap().unwrap(), @"9e15e977-f2ae-4761-943f-1eaf75fd736d");
+
+        // tasks
+        let tasks = dump.tasks().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"42d4200cf6d92a6449989ca48cd8e28a");
+        assert_eq!(update_files.len(), 22);
+        assert!(update_files[0].is_none()); // the dump creation
+        assert!(update_files[1].is_some()); // the enqueued document addition
+        assert!(update_files[2..].iter().all(|u| u.is_none())); // everything already processed
+
+        // keys
+        let keys = dump.keys().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys), @"c9d2b467fe2fca0b35580d8a999808fb");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"8e5cadabf74aebe1160bf51c3d489efe");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"b01c8371aea4c7171af0d4d846a2bdca");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"4894ac1e74b9e1069ed5ee262b7a1aca");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 200);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"e962baafd2fbae4cdd14e876053b0c5a");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"054dbf08a79e08bb9becba6f5d090f13");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+
+    #[test]
+    #[ignore]
+    fn import_dump_v4() {
+        let dump = File::open("tests/assets/v4.dump").unwrap();
+        let mut dump = DumpReader::open(dump).unwrap();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-06 12:53:49.131989609 +00:00:00");
+        insta::assert_display_snapshot!(dump.instance_uid().unwrap().unwrap(), @"9e15e977-f2ae-4761-943f-1eaf75fd736d");
+
+        // tasks
+        let tasks = dump.tasks().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"491e244a80a19fe2a900b809d310c24a");
+        assert_eq!(update_files.len(), 10);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        // keys
+        let keys = dump.keys().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys, { "[].uid" => "[uuid]" }), @"d751713988987e9331980363e24189ce");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"1f9da51a4518166fb440def5437eafdb");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"b01c8371aea4c7171af0d4d846a2bdca");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"488816aba82c1bd65f1609630055c611");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"786022a66ecb992c8a2a60fee070a5ab");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"7b4f66dad597dc651650f35fe34be27f");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+
+    #[test]
+    #[ignore]
+    fn import_dump_v3() {
+        let dump = File::open("tests/assets/v3.dump").unwrap();
+        let mut dump = DumpReader::open(dump).unwrap();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-07 11:39:03.709153554 +00:00:00");
+        assert_eq!(dump.instance_uid().unwrap(), None);
+
+        // tasks
+        let tasks = dump.tasks().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"7cacce2e21702be696b866808c726946");
+        assert_eq!(update_files.len(), 10);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        // keys
+        let keys = dump.keys().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys), @"d751713988987e9331980363e24189ce");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies2 = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"855f3165dec609b919171ff83f82b364");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"548284a84de510f71e88e6cdea495cf5");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"43e0bf1746c3ea1d64c1e10ea544c190");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d153b5a81d8b3cdcbe1dec270b574022");
+
+        // movies2
+        insta::assert_json_snapshot!(movies2.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies_2",
+          "primaryKey": null,
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies2.settings()), @"5fd06a5038f49311600379d43412b655");
+        let documents = movies2.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 0);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d751713988987e9331980363e24189ce");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"5fd06a5038f49311600379d43412b655");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+
+    #[test]
+    #[ignore]
+    fn import_dump_v2() {
+        let dump = File::open("tests/assets/v2.dump").unwrap();
+        let mut dump = DumpReader::open(dump).unwrap();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-09 20:27:59.904096267 +00:00:00");
+        assert_eq!(dump.instance_uid().unwrap(), None);
+
+        // tasks
+        let tasks = dump.tasks().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"6cabec4e252b74c8f3a2c8517622e85f");
+        assert_eq!(update_files.len(), 9);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        // keys
+        let keys = dump.keys().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys), @"d751713988987e9331980363e24189ce");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies2 = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"b15b71f56dd082d8e8ec5182e688bf36");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"548284a84de510f71e88e6cdea495cf5");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"5389153ddf5527fa79c54b6a6e9c21f6");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d153b5a81d8b3cdcbe1dec270b574022");
+
+        // movies2
+        insta::assert_json_snapshot!(movies2.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies_2",
+          "primaryKey": null,
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies2.settings()), @"8aebab01301d266acf3e18dd449c008f");
+        let documents = movies2.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 0);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d751713988987e9331980363e24189ce");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"8aebab01301d266acf3e18dd449c008f");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/v1/mod.rs

@@ -0,0 +1,173 @@
+use std::{
+    convert::Infallible,
+    fs::{self, File},
+    io::{BufRead, BufReader},
+    path::Path,
+};
+
+use tempfile::TempDir;
+use time::OffsetDateTime;
+
+use self::update::UpdateStatus;
+
+use super::{DumpReader, IndexReader};
+use crate::{Error, Result, Version};
+
+pub mod settings;
+pub mod update;
+pub mod v1;
+
+pub struct V1Reader {
+    dump: TempDir,
+    metadata: v1::Metadata,
+    indexes: Vec<V1IndexReader>,
+}
+
+struct V1IndexReader {
+    name: String,
+    documents: BufReader<File>,
+    settings: BufReader<File>,
+    updates: BufReader<File>,
+
+    current_update: Option<UpdateStatus>,
+}
+
+impl V1IndexReader {
+    pub fn new(name: String, path: &Path) -> Result<Self> {
+        let mut ret = V1IndexReader {
+            name,
+            documents: BufReader::new(File::open(path.join("documents.jsonl"))?),
+            settings: BufReader::new(File::open(path.join("settings.json"))?),
+            updates: BufReader::new(File::open(path.join("updates.jsonl"))?),
+            current_update: None,
+        };
+        ret.next_update();
+
+        Ok(ret)
+    }
+
+    pub fn next_update(&mut self) -> Result<Option<UpdateStatus>> {
+        let current_update = if let Some(line) = self.updates.lines().next() {
+            Some(serde_json::from_str(&line?)?)
+        } else {
+            None
+        };
+
+        Ok(std::mem::replace(&mut self.current_update, current_update))
+    }
+}
+
+impl V1Reader {
+    pub fn open(dump: TempDir) -> Result<Self> {
+        let mut meta_file = fs::read(dump.path().join("metadata.json"))?;
+        let metadata = serde_json::from_reader(&*meta_file)?;
+
+        let mut indexes = Vec::new();
+
+        let entries = fs::read_dir(dump.path())?;
+        for entry in entries {
+            let entry = entry?;
+            if entry.file_type()?.is_dir() {
+                indexes.push(V1IndexReader::new(
+                    entry
+                        .file_name()
+                        .to_str()
+                        .ok_or(Error::BadIndexName)?
+                        .to_string(),
+                    &entry.path(),
+                )?);
+            }
+        }
+
+        Ok(V1Reader {
+            dump,
+            metadata,
+            indexes,
+        })
+    }
+
+    fn next_update(&mut self) -> Result<Option<UpdateStatus>> {
+        if let Some((idx, _)) = self
+            .indexes
+            .iter()
+            .map(|index| index.current_update)
+            .enumerate()
+            .filter_map(|(idx, update)| update.map(|u| (idx, u)))
+            .min_by_key(|(_, update)| update.enqueued_at())
+        {
+            self.indexes[idx].next_update()
+        } else {
+            Ok(None)
+        }
+    }
+}
+
+impl IndexReader for &V1IndexReader {
+    type Document = serde_json::Map<String, serde_json::Value>;
+    type Settings = settings::Settings;
+
+    fn name(&self) -> &str {
+        todo!()
+    }
+
+    fn documents(&self) -> Result<Box<dyn Iterator<Item = Result<Self::Document>>>> {
+        todo!()
+    }
+
+    fn settings(&self) -> Result<Self::Settings> {
+        todo!()
+    }
+}
+
+impl DumpReader for V1Reader {
+    type Document = serde_json::Map<String, serde_json::Value>;
+    type Settings = settings::Settings;
+
+    type Task = update::UpdateStatus;
+    type UpdateFile = Infallible;
+
+    type Key = Infallible;
+
+    fn date(&self) -> Option<OffsetDateTime> {
+        None
+    }
+
+    fn version(&self) -> Version {
+        Version::V1
+    }
+
+    fn indexes(
+        &self,
+    ) -> Result<
+        Box<
+            dyn Iterator<
+                Item = Result<
+                    Box<
+                        dyn super::IndexReader<
+                            Document = Self::Document,
+                            Settings = Self::Settings,
+                        >,
+                    >,
+                >,
+            >,
+        >,
+    > {
+        Ok(Box::new(self.indexes.iter().map(|index| {
+            let index = Box::new(index)
+                as Box<dyn IndexReader<Document = Self::Document, Settings = Self::Settings>>;
+            Ok(index)
+        })))
+    }
+
+    fn tasks(&self) -> Box<dyn Iterator<Item = Result<(Self::Task, Option<Self::UpdateFile>)>>> {
+        Box::new(std::iter::from_fn(|| {
+            self.next_update()
+                .transpose()
+                .map(|result| result.map(|task| (task, None)))
+        }))
+    }
+
+    fn keys(&self) -> Box<dyn Iterator<Item = Result<Self::Key>>> {
+        Box::new(std::iter::empty())
+    }
+}

dump/src/reader/v1/settings.rs

@@ -0,0 +1,63 @@
+use std::collections::{BTreeMap, BTreeSet};
+use std::result::Result as StdResult;
+
+use serde::{Deserialize, Deserializer, Serialize};
+
+#[derive(Default, Clone, Serialize, Deserialize, Debug)]
+#[serde(rename_all = "camelCase", deny_unknown_fields)]
+pub struct Settings {
+    #[serde(default, deserialize_with = "deserialize_some")]
+    pub ranking_rules: Option<Option<Vec<String>>>,
+    #[serde(default, deserialize_with = "deserialize_some")]
+    pub distinct_attribute: Option<Option<String>>,
+    #[serde(default, deserialize_with = "deserialize_some")]
+    pub searchable_attributes: Option<Option<Vec<String>>>,
+    #[serde(default, deserialize_with = "deserialize_some")]
+    pub displayed_attributes: Option<Option<BTreeSet<String>>>,
+    #[serde(default, deserialize_with = "deserialize_some")]
+    pub stop_words: Option<Option<BTreeSet<String>>>,
+    #[serde(default, deserialize_with = "deserialize_some")]
+    pub synonyms: Option<Option<BTreeMap<String, Vec<String>>>>,
+    #[serde(default, deserialize_with = "deserialize_some")]
+    pub attributes_for_faceting: Option<Option<Vec<String>>>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SettingsUpdate {
+    pub ranking_rules: UpdateState<Vec<RankingRule>>,
+    pub distinct_attribute: UpdateState<String>,
+    pub primary_key: UpdateState<String>,
+    pub searchable_attributes: UpdateState<Vec<String>>,
+    pub displayed_attributes: UpdateState<BTreeSet<String>>,
+    pub stop_words: UpdateState<BTreeSet<String>>,
+    pub synonyms: UpdateState<BTreeMap<String, Vec<String>>>,
+    pub attributes_for_faceting: UpdateState<Vec<String>>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum UpdateState<T> {
+    Update(T),
+    Clear,
+    Nothing,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum RankingRule {
+    Typo,
+    Words,
+    Proximity,
+    Attribute,
+    WordsPosition,
+    Exactness,
+    Asc(String),
+    Desc(String),
+}
+
+// Any value that is present is considered Some value, including null.
+fn deserialize_some<'de, T, D>(deserializer: D) -> StdResult<Option<T>, D::Error>
+where
+    T: Deserialize<'de>,
+    D: Deserializer<'de>,
+{
+    Deserialize::deserialize(deserializer).map(Some)
+}

dump/src/reader/v1/update.rs

@@ -0,0 +1,120 @@
+use serde::{Deserialize, Serialize};
+use serde_json::Value;
+use time::OffsetDateTime;
+
+use super::settings::SettingsUpdate;
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Update {
+    data: UpdateData,
+    #[serde(with = "time::serde::rfc3339")]
+    enqueued_at: OffsetDateTime,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum UpdateData {
+    ClearAll,
+    Customs(Vec<u8>),
+    // (primary key, documents)
+    DocumentsAddition {
+        primary_key: Option<String>,
+        documents: Vec<serde_json::Map<String, Value>>,
+    },
+    DocumentsPartial {
+        primary_key: Option<String>,
+        documents: Vec<serde_json::Map<String, Value>>,
+    },
+    DocumentsDeletion(Vec<String>),
+    Settings(Box<SettingsUpdate>),
+}
+
+impl UpdateData {
+    pub fn update_type(&self) -> UpdateType {
+        match self {
+            UpdateData::ClearAll => UpdateType::ClearAll,
+            UpdateData::Customs(_) => UpdateType::Customs,
+            UpdateData::DocumentsAddition { documents, .. } => UpdateType::DocumentsAddition {
+                number: documents.len(),
+            },
+            UpdateData::DocumentsPartial { documents, .. } => UpdateType::DocumentsPartial {
+                number: documents.len(),
+            },
+            UpdateData::DocumentsDeletion(deletion) => UpdateType::DocumentsDeletion {
+                number: deletion.len(),
+            },
+            UpdateData::Settings(update) => UpdateType::Settings {
+                settings: update.clone(),
+            },
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(tag = "name")]
+pub enum UpdateType {
+    ClearAll,
+    Customs,
+    DocumentsAddition { number: usize },
+    DocumentsPartial { number: usize },
+    DocumentsDeletion { number: usize },
+    Settings { settings: Box<SettingsUpdate> },
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ProcessedUpdateResult {
+    pub update_id: u64,
+    #[serde(rename = "type")]
+    pub update_type: UpdateType,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub error: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub error_type: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub error_code: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub error_link: Option<String>,
+    pub duration: f64, // in seconds
+    #[serde(with = "time::serde::rfc3339")]
+    pub enqueued_at: OffsetDateTime,
+    #[serde(with = "time::serde::rfc3339")]
+    pub processed_at: OffsetDateTime,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct EnqueuedUpdateResult {
+    pub update_id: u64,
+    #[serde(rename = "type")]
+    pub update_type: UpdateType,
+    #[serde(with = "time::serde::rfc3339")]
+    pub enqueued_at: OffsetDateTime,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase", tag = "status")]
+pub enum UpdateStatus {
+    Enqueued {
+        #[serde(flatten)]
+        content: EnqueuedUpdateResult,
+    },
+    Failed {
+        #[serde(flatten)]
+        content: ProcessedUpdateResult,
+    },
+    Processed {
+        #[serde(flatten)]
+        content: ProcessedUpdateResult,
+    },
+}
+
+impl UpdateStatus {
+    pub fn enqueued_at(&self) -> &OffsetDateTime {
+        match self {
+            UpdateStatus::Enqueued { content } => &content.enqueued_at,
+            UpdateStatus::Failed { content } | UpdateStatus::Processed { content } => {
+                &content.enqueued_at
+            }
+        }
+    }
+}

dump/src/reader/v1/v1.rs

@@ -0,0 +1,22 @@
+use serde::Deserialize;
+use time::OffsetDateTime;
+
+#[derive(Debug, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct Index {
+    pub name: String,
+    pub uid: String,
+    #[serde(with = "time::serde::rfc3339")]
+    created_at: OffsetDateTime,
+    #[serde(with = "time::serde::rfc3339")]
+    updated_at: OffsetDateTime,
+    pub primary_key: Option<String>,
+}
+
+#[derive(Debug, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct Metadata {
+    indexes: Vec<Index>,
+    db_version: String,
+    dump_version: crate::Version,
+}

dump/src/reader/v2/errors.rs

@@ -0,0 +1,14 @@
+use http::StatusCode;
+use serde::Deserialize;
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct ResponseError {
+    #[serde(skip)]
+    pub code: StatusCode,
+    pub message: String,
+    pub error_code: String,
+    pub error_type: String,
+    pub error_link: String,
+}

dump/src/reader/v2/meta.rs

@@ -0,0 +1,18 @@
+use serde::Deserialize;
+use uuid::Uuid;
+
+use super::Settings;
+
+#[derive(Deserialize, Debug, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct IndexUuid {
+    pub uid: String,
+    pub uuid: Uuid,
+}
+
+#[derive(Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct DumpMeta {
+    pub settings: Settings<super::Unchecked>,
+    pub primary_key: Option<String>,
+}

dump/src/reader/v2/mod.rs

@@ -0,0 +1,310 @@
+//! ```text
+//! .
+//! ├── indexes
+//! │   ├── index-40d14c5f-37ae-4873-9d51-b69e014a0d30
+//! │   │   ├── documents.jsonl
+//! │   │   └── meta.json
+//! │   ├── index-88202369-4524-4410-9b3d-3e924c867fec
+//! │   │   ├── documents.jsonl
+//! │   │   └── meta.json
+//! │   ├── index-b7f2d03b-bf9b-40d9-a25b-94dc5ec60c32
+//! │   │   ├── documents.jsonl
+//! │   │   └── meta.json
+//! │   └── index-dc9070b3-572d-4f30-ab45-d4903ab71708
+//! │       ├── documents.jsonl
+//! │       └── meta.json
+//! ├── index_uuids
+//! │   └── data.jsonl
+//! ├── metadata.json
+//! └── updates
+//!     ├── data.jsonl
+//!     └── update_files
+//!         └── update_202573df-718b-4d80-9a65-2ee397c23dc3
+//! ```
+
+use std::fs::{self, File};
+use std::io::{BufRead, BufReader};
+use std::path::Path;
+
+use serde::{Deserialize, Serialize};
+use tempfile::TempDir;
+use time::OffsetDateTime;
+
+pub mod errors;
+pub mod meta;
+pub mod settings;
+pub mod updates;
+
+use self::meta::{DumpMeta, IndexUuid};
+use super::compat::v2_to_v3::CompatV2ToV3;
+use super::Document;
+use crate::{IndexMetadata, Result, Version};
+
+pub type Settings<T> = settings::Settings<T>;
+pub type Checked = settings::Checked;
+pub type Unchecked = settings::Unchecked;
+
+pub type Task = updates::UpdateEntry;
+
+// everything related to the errors
+pub type ResponseError = errors::ResponseError;
+
+#[derive(Serialize, Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct Metadata {
+    db_version: String,
+    index_db_size: usize,
+    update_db_size: usize,
+    #[serde(with = "time::serde::rfc3339")]
+    dump_date: OffsetDateTime,
+}
+
+pub struct V2Reader {
+    dump: TempDir,
+    metadata: Metadata,
+    tasks: BufReader<File>,
+    pub index_uuid: Vec<IndexUuid>,
+}
+
+impl V2Reader {
+    pub fn open(dump: TempDir) -> Result<Self> {
+        let meta_file = fs::read(dump.path().join("metadata.json"))?;
+        let metadata = serde_json::from_reader(&*meta_file)?;
+        let index_uuid = File::open(dump.path().join("index_uuids/data.jsonl"))?;
+        let index_uuid = BufReader::new(index_uuid);
+        let index_uuid = index_uuid
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) })
+            .collect::<Result<Vec<_>>>()?;
+
+        Ok(V2Reader {
+            metadata,
+            tasks: BufReader::new(
+                File::open(dump.path().join("updates").join("data.jsonl")).unwrap(),
+            ),
+            index_uuid,
+            dump,
+        })
+    }
+
+    pub fn to_v3(self) -> CompatV2ToV3 {
+        CompatV2ToV3::new(self)
+    }
+
+    pub fn index_uuid(&self) -> Vec<IndexUuid> {
+        self.index_uuid.clone()
+    }
+
+    pub fn version(&self) -> Version {
+        Version::V2
+    }
+
+    pub fn date(&self) -> Option<OffsetDateTime> {
+        Some(self.metadata.dump_date)
+    }
+
+    pub fn indexes(&self) -> Result<impl Iterator<Item = Result<V2IndexReader>> + '_> {
+        Ok(self.index_uuid.iter().map(|index| -> Result<_> {
+            V2IndexReader::new(
+                index.uid.clone(),
+                &self.dump.path().join("indexes").join(format!("index-{}", index.uuid)),
+            )
+        }))
+    }
+
+    pub fn tasks(&mut self) -> Box<dyn Iterator<Item = Result<(Task, Option<UpdateFile>)>> + '_> {
+        Box::new((&mut self.tasks).lines().map(|line| -> Result<_> {
+            let task: Task = serde_json::from_str(&line?)?;
+            if !task.is_finished() {
+                if let Some(uuid) = task.get_content_uuid() {
+                    let update_file_path = self
+                        .dump
+                        .path()
+                        .join("updates")
+                        .join("update_files")
+                        .join(format!("update_{}", uuid));
+                    Ok((task, Some(UpdateFile::new(&update_file_path)?)))
+                } else {
+                    Ok((task, None))
+                }
+            } else {
+                Ok((task, None))
+            }
+        }))
+    }
+}
+
+pub struct V2IndexReader {
+    metadata: IndexMetadata,
+    settings: Settings<Checked>,
+
+    documents: BufReader<File>,
+}
+
+impl V2IndexReader {
+    pub fn new(name: String, path: &Path) -> Result<Self> {
+        let meta = File::open(path.join("meta.json"))?;
+        let meta: DumpMeta = serde_json::from_reader(meta)?;
+
+        let metadata = IndexMetadata {
+            uid: name,
+            primary_key: meta.primary_key,
+            // FIXME: Iterate over the whole task queue to find the creation and last update date.
+            created_at: OffsetDateTime::now_utc(),
+            updated_at: OffsetDateTime::now_utc(),
+        };
+
+        let ret = V2IndexReader {
+            metadata,
+            settings: meta.settings.check(),
+            documents: BufReader::new(File::open(path.join("documents.jsonl"))?),
+        };
+
+        Ok(ret)
+    }
+
+    pub fn metadata(&self) -> &IndexMetadata {
+        &self.metadata
+    }
+
+    pub fn documents(&mut self) -> Result<impl Iterator<Item = Result<Document>> + '_> {
+        Ok((&mut self.documents)
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) }))
+    }
+
+    pub fn settings(&mut self) -> Result<Settings<Checked>> {
+        Ok(self.settings.clone())
+    }
+}
+
+pub struct UpdateFile {
+    documents: Vec<Document>,
+    index: usize,
+}
+
+impl UpdateFile {
+    fn new(path: &Path) -> Result<Self> {
+        let reader = BufReader::new(File::open(path)?);
+        Ok(UpdateFile { documents: serde_json::from_reader(reader)?, index: 0 })
+    }
+}
+
+impl Iterator for UpdateFile {
+    type Item = Result<Document>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.index += 1;
+        self.documents.get(self.index - 1).cloned().map(Ok)
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::BufReader;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use tempfile::TempDir;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn read_dump_v2() {
+        let dump = File::open("tests/assets/v2.dump").unwrap();
+        let dir = TempDir::new().unwrap();
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(dir.path()).unwrap();
+
+        let mut dump = V2Reader::open(dir).unwrap();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-09 20:27:59.904096267 +00:00:00");
+
+        // tasks
+        let tasks = dump.tasks().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, mut update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"ec5fc0a14bf735ad4e361d5aa8a89ac6");
+        assert_eq!(update_files.len(), 9);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        let update_file = update_files.remove(0).unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(update_file), @"7b8889539b669c7b9ddba448bafa385d");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies2 = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"c41bf7315d404da46c99b9e3a2a3cc1e");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"548284a84de510f71e88e6cdea495cf5");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"3d1d96c85b6bab46e957bc8d2532a910");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d153b5a81d8b3cdcbe1dec270b574022");
+
+        // movies2
+        insta::assert_json_snapshot!(movies2.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies_2",
+          "primaryKey": null,
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies2.settings()), @"4f04afc086828d8da0da57a7d598ddba");
+        let documents = movies2.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 0);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d751713988987e9331980363e24189ce");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"4f04afc086828d8da0da57a7d598ddba");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/v2/settings.rs

@@ -0,0 +1,176 @@
+use std::collections::{BTreeMap, BTreeSet};
+use std::marker::PhantomData;
+use std::str::FromStr;
+
+use once_cell::sync::Lazy;
+use regex::Regex;
+use serde::{Deserialize, Deserializer};
+
+#[cfg(test)]
+fn serialize_with_wildcard<S>(
+    field: &Option<Option<Vec<String>>>,
+    s: S,
+) -> std::result::Result<S::Ok, S::Error>
+where
+    S: serde::Serializer,
+{
+    let wildcard = vec!["*".to_string()];
+    s.serialize_some(&field.as_ref().map(|o| o.as_ref().unwrap_or(&wildcard)))
+}
+
+fn deserialize_some<'de, T, D>(deserializer: D) -> std::result::Result<Option<T>, D::Error>
+where
+    T: Deserialize<'de>,
+    D: Deserializer<'de>,
+{
+    Deserialize::deserialize(deserializer).map(Some)
+}
+
+#[derive(Clone, Default, Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Checked;
+#[derive(Clone, Default, Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Unchecked;
+
+#[derive(Debug, Clone, Default, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+#[serde(bound(serialize = "T: serde::Serialize", deserialize = "T: Deserialize<'static>"))]
+pub struct Settings<T> {
+    #[serde(
+        default,
+        deserialize_with = "deserialize_some",
+        serialize_with = "serialize_with_wildcard",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub displayed_attributes: Option<Option<Vec<String>>>,
+
+    #[serde(
+        default,
+        deserialize_with = "deserialize_some",
+        serialize_with = "serialize_with_wildcard",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub searchable_attributes: Option<Option<Vec<String>>>,
+
+    #[serde(
+        default,
+        deserialize_with = "deserialize_some",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub filterable_attributes: Option<Option<BTreeSet<String>>>,
+
+    #[serde(
+        default,
+        deserialize_with = "deserialize_some",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub ranking_rules: Option<Option<Vec<String>>>,
+    #[serde(
+        default,
+        deserialize_with = "deserialize_some",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub stop_words: Option<Option<BTreeSet<String>>>,
+    #[serde(
+        default,
+        deserialize_with = "deserialize_some",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub synonyms: Option<Option<BTreeMap<String, Vec<String>>>>,
+    #[serde(
+        default,
+        deserialize_with = "deserialize_some",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub distinct_attribute: Option<Option<String>>,
+
+    #[serde(skip)]
+    pub _kind: PhantomData<T>,
+}
+
+impl Settings<Unchecked> {
+    pub fn check(mut self) -> Settings<Checked> {
+        let displayed_attributes = match self.displayed_attributes.take() {
+            Some(Some(fields)) => {
+                if fields.iter().any(|f| f == "*") {
+                    Some(None)
+                } else {
+                    Some(Some(fields))
+                }
+            }
+            otherwise => otherwise,
+        };
+
+        let searchable_attributes = match self.searchable_attributes.take() {
+            Some(Some(fields)) => {
+                if fields.iter().any(|f| f == "*") {
+                    Some(None)
+                } else {
+                    Some(Some(fields))
+                }
+            }
+            otherwise => otherwise,
+        };
+
+        Settings {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes: self.filterable_attributes,
+            ranking_rules: self.ranking_rules,
+            stop_words: self.stop_words,
+            synonyms: self.synonyms,
+            distinct_attribute: self.distinct_attribute,
+            _kind: PhantomData,
+        }
+    }
+}
+
+static ASC_DESC_REGEX: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r#"(asc|desc)\(([\w_-]+)\)"#).unwrap());
+
+#[derive(Debug, Deserialize, Clone, PartialEq, Eq)]
+pub enum Criterion {
+    /// Sorted by decreasing number of matched query terms.
+    /// Query words at the front of an attribute is considered better than if it was at the back.
+    Words,
+    /// Sorted by increasing number of typos.
+    Typo,
+    /// Sorted by increasing distance between matched query terms.
+    Proximity,
+    /// Documents with quey words contained in more important
+    /// attributes are considred better.
+    Attribute,
+    /// Sorted by the similarity of the matched words with the query words.
+    Exactness,
+    /// Sorted by the increasing value of the field specified.
+    Asc(String),
+    /// Sorted by the decreasing value of the field specified.
+    Desc(String),
+}
+
+impl FromStr for Criterion {
+    type Err = ();
+
+    fn from_str(txt: &str) -> Result<Criterion, Self::Err> {
+        match txt {
+            "words" => Ok(Criterion::Words),
+            "typo" => Ok(Criterion::Typo),
+            "proximity" => Ok(Criterion::Proximity),
+            "attribute" => Ok(Criterion::Attribute),
+            "exactness" => Ok(Criterion::Exactness),
+            text => {
+                let caps = ASC_DESC_REGEX.captures(text).ok_or(())?;
+                let order = caps.get(1).unwrap().as_str();
+                let field_name = caps.get(2).unwrap().as_str();
+                match order {
+                    "asc" => Ok(Criterion::Asc(field_name.to_string())),
+                    "desc" => Ok(Criterion::Desc(field_name.to_string())),
+                    _text => Err(()),
+                }
+            }
+        }
+    }
+}

dump/src/reader/v2/updates.rs

@@ -0,0 +1,230 @@
+use serde::Deserialize;
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+use super::{ResponseError, Settings, Unchecked};
+
+#[derive(Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct UpdateEntry {
+    pub uuid: Uuid,
+    pub update: UpdateStatus,
+}
+
+impl UpdateEntry {
+    pub fn is_finished(&self) -> bool {
+        match self.update {
+            UpdateStatus::Processing(_) | UpdateStatus::Enqueued(_) => false,
+            UpdateStatus::Processed(_) | UpdateStatus::Aborted(_) | UpdateStatus::Failed(_) => true,
+        }
+    }
+
+    pub fn get_content_uuid(&self) -> Option<&Uuid> {
+        match &self.update {
+            UpdateStatus::Enqueued(enqueued) => enqueued.content.as_ref(),
+            UpdateStatus::Processing(processing) => processing.from.content.as_ref(),
+            UpdateStatus::Processed(processed) => processed.from.from.content.as_ref(),
+            UpdateStatus::Aborted(aborted) => aborted.from.content.as_ref(),
+            UpdateStatus::Failed(failed) => failed.from.from.content.as_ref(),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum UpdateResult {
+    DocumentsAddition(DocumentAdditionResult),
+    DocumentDeletion { deleted: u64 },
+    Other,
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct DocumentAdditionResult {
+    pub nb_documents: usize,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[non_exhaustive]
+pub enum IndexDocumentsMethod {
+    /// Replace the previous document with the new one,
+    /// removing all the already known attributes.
+    ReplaceDocuments,
+
+    /// Merge the previous version of the document with the new version,
+    /// replacing old attributes values with the new ones and add the new attributes.
+    UpdateDocuments,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[non_exhaustive]
+pub enum UpdateFormat {
+    /// The given update is a real **comma seperated** CSV with headers on the first line.
+    Csv,
+    /// The given update is a JSON array with documents inside.
+    Json,
+    /// The given update is a JSON stream with a document on each line.
+    JsonStream,
+}
+
+#[allow(clippy::large_enum_variant)]
+#[derive(Debug, Clone, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(tag = "type")]
+pub enum UpdateMeta {
+    DocumentsAddition {
+        method: IndexDocumentsMethod,
+        format: UpdateFormat,
+        primary_key: Option<String>,
+    },
+    ClearDocuments,
+    DeleteDocuments {
+        ids: Vec<String>,
+    },
+    Settings(Settings<Unchecked>),
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Enqueued {
+    pub update_id: u64,
+    pub meta: UpdateMeta,
+    #[serde(with = "time::serde::rfc3339")]
+    pub enqueued_at: OffsetDateTime,
+    pub content: Option<Uuid>,
+}
+
+impl Enqueued {
+    pub fn meta(&self) -> &UpdateMeta {
+        &self.meta
+    }
+
+    pub fn id(&self) -> u64 {
+        self.update_id
+    }
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Processed {
+    pub success: UpdateResult,
+    #[serde(with = "time::serde::rfc3339")]
+    pub processed_at: OffsetDateTime,
+    #[serde(flatten)]
+    pub from: Processing,
+}
+
+impl Processed {
+    pub fn id(&self) -> u64 {
+        self.from.id()
+    }
+
+    pub fn meta(&self) -> &UpdateMeta {
+        self.from.meta()
+    }
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Processing {
+    #[serde(flatten)]
+    pub from: Enqueued,
+    #[serde(with = "time::serde::rfc3339")]
+    pub started_processing_at: OffsetDateTime,
+}
+
+impl Processing {
+    pub fn id(&self) -> u64 {
+        self.from.id()
+    }
+
+    pub fn meta(&self) -> &UpdateMeta {
+        self.from.meta()
+    }
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Aborted {
+    #[serde(flatten)]
+    pub from: Enqueued,
+    #[serde(with = "time::serde::rfc3339")]
+    pub aborted_at: OffsetDateTime,
+}
+
+impl Aborted {
+    pub fn id(&self) -> u64 {
+        self.from.id()
+    }
+
+    pub fn meta(&self) -> &UpdateMeta {
+        self.from.meta()
+    }
+}
+
+#[derive(Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Failed {
+    #[serde(flatten)]
+    pub from: Processing,
+    pub error: ResponseError,
+    #[serde(with = "time::serde::rfc3339")]
+    pub failed_at: OffsetDateTime,
+}
+
+impl Failed {
+    pub fn id(&self) -> u64 {
+        self.from.id()
+    }
+
+    pub fn meta(&self) -> &UpdateMeta {
+        self.from.meta()
+    }
+}
+
+#[derive(Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(tag = "status", rename_all = "camelCase")]
+pub enum UpdateStatus {
+    Processing(Processing),
+    Enqueued(Enqueued),
+    Processed(Processed),
+    Aborted(Aborted),
+    Failed(Failed),
+}
+
+impl UpdateStatus {
+    pub fn id(&self) -> u64 {
+        match self {
+            UpdateStatus::Processing(u) => u.id(),
+            UpdateStatus::Enqueued(u) => u.id(),
+            UpdateStatus::Processed(u) => u.id(),
+            UpdateStatus::Aborted(u) => u.id(),
+            UpdateStatus::Failed(u) => u.id(),
+        }
+    }
+
+    pub fn meta(&self) -> &UpdateMeta {
+        match self {
+            UpdateStatus::Processing(u) => u.meta(),
+            UpdateStatus::Enqueued(u) => u.meta(),
+            UpdateStatus::Processed(u) => u.meta(),
+            UpdateStatus::Aborted(u) => u.meta(),
+            UpdateStatus::Failed(u) => u.meta(),
+        }
+    }
+
+    pub fn processed(&self) -> Option<&Processed> {
+        match self {
+            UpdateStatus::Processed(p) => Some(p),
+            _ => None,
+        }
+    }
+}

dump/src/reader/v3/errors.rs

@@ -0,0 +1,51 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Serialize, Deserialize, Debug, Clone, Copy)]
+pub enum Code {
+    // index related error
+    CreateIndex,
+    IndexAlreadyExists,
+    IndexNotFound,
+    InvalidIndexUid,
+
+    // invalid state error
+    InvalidState,
+    MissingPrimaryKey,
+    PrimaryKeyAlreadyPresent,
+
+    MaxFieldsLimitExceeded,
+    MissingDocumentId,
+    InvalidDocumentId,
+
+    Filter,
+    Sort,
+
+    BadParameter,
+    BadRequest,
+    DatabaseSizeLimitReached,
+    DocumentNotFound,
+    Internal,
+    InvalidGeoField,
+    InvalidRankingRule,
+    InvalidStore,
+    InvalidToken,
+    MissingAuthorizationHeader,
+    NoSpaceLeftOnDevice,
+    DumpNotFound,
+    TaskNotFound,
+    PayloadTooLarge,
+    RetrieveDocument,
+    SearchDocuments,
+    UnsupportedMediaType,
+
+    DumpAlreadyInProgress,
+    DumpProcessFailed,
+
+    InvalidContentType,
+    MissingContentType,
+    MalformedPayload,
+    MissingPayload,
+
+    MalformedDump,
+    UnretrievableErrorCode,
+}

dump/src/reader/v3/meta.rs

@@ -0,0 +1,18 @@
+use serde::Deserialize;
+use uuid::Uuid;
+
+use super::Settings;
+
+#[derive(Deserialize, Debug, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct IndexUuid {
+    pub uid: String,
+    pub uuid: Uuid,
+}
+
+#[derive(Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct DumpMeta {
+    pub settings: Settings<super::Unchecked>,
+    pub primary_key: Option<String>,
+}

dump/src/reader/v3/mod.rs

@@ -0,0 +1,326 @@
+//! ```text
+//! .
+//! ├── indexes
+//! │   ├── 01d7dd17-8241-4f1f-a7d1-2d1cb255f5b0
+//! │   │   ├── documents.jsonl
+//! │   │   └── meta.json
+//! │   ├── 78be64a3-cae1-449e-b7ed-13e77c9a8a0c
+//! │   │   ├── documents.jsonl
+//! │   │   └── meta.json
+//! │   ├── ba553439-18fe-4733-ba53-44eed898280c
+//! │   │   ├── documents.jsonl
+//! │   │   └── meta.json
+//! │   └── c408bc22-5859-49d1-8e9f-c88e2fa95cb0
+//! │       ├── documents.jsonl
+//! │       └── meta.json
+//! ├── index_uuids
+//! │   └── data.jsonl
+//! ├── metadata.json
+//! └── updates
+//!     ├── data.jsonl
+//!     └── updates_files
+//!         └── 66d3f12d-fcf3-4b53-88cb-407017373de7
+//! ```
+
+use std::fs::{self, File};
+use std::io::{BufRead, BufReader};
+use std::path::Path;
+
+use serde::{Deserialize, Serialize};
+use tempfile::TempDir;
+use time::OffsetDateTime;
+
+pub mod errors;
+pub mod meta;
+pub mod settings;
+pub mod updates;
+
+use self::meta::{DumpMeta, IndexUuid};
+use super::compat::v3_to_v4::CompatV3ToV4;
+use super::Document;
+use crate::{Error, IndexMetadata, Result, Version};
+
+pub type Settings<T> = settings::Settings<T>;
+pub type Checked = settings::Checked;
+pub type Unchecked = settings::Unchecked;
+
+pub type Task = updates::UpdateEntry;
+
+// ===== Other types to clarify the code of the compat module
+// everything related to the tasks
+pub type Status = updates::UpdateStatus;
+pub type Kind = updates::Update;
+
+// everything related to the settings
+pub type Setting<T> = settings::Setting<T>;
+
+// everything related to the errors
+pub type Code = errors::Code;
+
+#[derive(Serialize, Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct Metadata {
+    db_version: String,
+    index_db_size: usize,
+    update_db_size: usize,
+    #[serde(with = "time::serde::rfc3339")]
+    dump_date: OffsetDateTime,
+}
+
+pub struct V3Reader {
+    dump: TempDir,
+    metadata: Metadata,
+    tasks: BufReader<File>,
+    index_uuid: Vec<IndexUuid>,
+}
+
+impl V3Reader {
+    pub fn open(dump: TempDir) -> Result<Self> {
+        let meta_file = fs::read(dump.path().join("metadata.json"))?;
+        let metadata = serde_json::from_reader(&*meta_file)?;
+        let index_uuid = File::open(dump.path().join("index_uuids/data.jsonl"))?;
+        let index_uuid = BufReader::new(index_uuid);
+        let index_uuid = index_uuid
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) })
+            .collect::<Result<Vec<_>>>()?;
+
+        Ok(V3Reader {
+            metadata,
+            tasks: BufReader::new(File::open(dump.path().join("updates").join("data.jsonl"))?),
+            index_uuid,
+            dump,
+        })
+    }
+
+    pub fn index_uuid(&self) -> Vec<IndexUuid> {
+        self.index_uuid.clone()
+    }
+
+    pub fn to_v4(self) -> CompatV3ToV4 {
+        CompatV3ToV4::new(self)
+    }
+
+    pub fn version(&self) -> Version {
+        Version::V3
+    }
+
+    pub fn date(&self) -> Option<OffsetDateTime> {
+        Some(self.metadata.dump_date)
+    }
+
+    pub fn indexes(&self) -> Result<impl Iterator<Item = Result<V3IndexReader>> + '_> {
+        Ok(self.index_uuid.iter().map(|index| -> Result<_> {
+            V3IndexReader::new(
+                index.uid.clone(),
+                &self.dump.path().join("indexes").join(index.uuid.to_string()),
+            )
+        }))
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Box<dyn Iterator<Item = Result<(Task, Option<Box<super::UpdateFile>>)>> + '_> {
+        Box::new((&mut self.tasks).lines().map(|line| -> Result<_> {
+            let task: Task = serde_json::from_str(&line?)?;
+            if !task.is_finished() {
+                if let Some(uuid) = task.get_content_uuid() {
+                    let update_file_path = self
+                        .dump
+                        .path()
+                        .join("updates")
+                        .join("updates_files")
+                        .join(uuid.to_string());
+                    Ok((
+                        task,
+                        Some(
+                            Box::new(UpdateFile::new(&update_file_path)?) as Box<super::UpdateFile>
+                        ),
+                    ))
+                } else {
+                    Ok((task, None))
+                }
+            } else {
+                Ok((task, None))
+            }
+        }))
+    }
+}
+
+pub struct V3IndexReader {
+    metadata: IndexMetadata,
+    settings: Settings<Checked>,
+
+    documents: BufReader<File>,
+}
+
+impl V3IndexReader {
+    pub fn new(name: String, path: &Path) -> Result<Self> {
+        let meta = File::open(path.join("meta.json"))?;
+        let meta: DumpMeta = serde_json::from_reader(meta)?;
+
+        let metadata = IndexMetadata {
+            uid: name,
+            primary_key: meta.primary_key,
+            // FIXME: Iterate over the whole task queue to find the creation and last update date.
+            created_at: OffsetDateTime::now_utc(),
+            updated_at: OffsetDateTime::now_utc(),
+        };
+
+        let ret = V3IndexReader {
+            metadata,
+            settings: meta.settings.check(),
+            documents: BufReader::new(File::open(path.join("documents.jsonl"))?),
+        };
+
+        Ok(ret)
+    }
+
+    pub fn metadata(&self) -> &IndexMetadata {
+        &self.metadata
+    }
+
+    pub fn documents(&mut self) -> Result<impl Iterator<Item = Result<Document>> + '_> {
+        Ok((&mut self.documents)
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) }))
+    }
+
+    pub fn settings(&mut self) -> Result<Settings<Checked>> {
+        Ok(self.settings.clone())
+    }
+}
+
+pub struct UpdateFile {
+    reader: BufReader<File>,
+}
+
+impl UpdateFile {
+    fn new(path: &Path) -> Result<Self> {
+        Ok(UpdateFile { reader: BufReader::new(File::open(path)?) })
+    }
+}
+
+impl Iterator for UpdateFile {
+    type Item = Result<Document>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        (&mut self.reader)
+            .lines()
+            .map(|line| {
+                line.map_err(Error::from)
+                    .and_then(|line| serde_json::from_str(&line).map_err(Error::from))
+            })
+            .next()
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::BufReader;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use tempfile::TempDir;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn read_dump_v3() {
+        let dump = File::open("tests/assets/v3.dump").unwrap();
+        let dir = TempDir::new().unwrap();
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(dir.path()).unwrap();
+
+        let mut dump = V3Reader::open(dir).unwrap();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-07 11:39:03.709153554 +00:00:00");
+
+        // tasks
+        let tasks = dump.tasks().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, mut update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"63086d59c3f2074e4ab3fff7e8cc36c1");
+        assert_eq!(update_files.len(), 10);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        let update_file = update_files.remove(0).unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(update_file), @"7b8889539b669c7b9ddba448bafa385d");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies2 = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"f309b009608cc0b770b2f74516f92647");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"548284a84de510f71e88e6cdea495cf5");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"95dff22ba3a7019616c12df9daa35e1e");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d153b5a81d8b3cdcbe1dec270b574022");
+
+        // movies2
+        insta::assert_json_snapshot!(movies2.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies_2",
+          "primaryKey": null,
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies2.settings()), @"1dafc4b123e3a8e14a889719cc01f6e5");
+        let documents = movies2.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 0);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"d751713988987e9331980363e24189ce");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"1dafc4b123e3a8e14a889719cc01f6e5");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/v3/settings.rs

@@ -0,0 +1,233 @@
+use std::collections::{BTreeMap, BTreeSet};
+use std::marker::PhantomData;
+use std::num::NonZeroUsize;
+
+use serde::{Deserialize, Deserializer};
+
+#[cfg(test)]
+fn serialize_with_wildcard<S>(
+    field: &Setting<Vec<String>>,
+    s: S,
+) -> std::result::Result<S::Ok, S::Error>
+where
+    S: serde::Serializer,
+{
+    use serde::Serialize;
+
+    let wildcard = vec!["*".to_string()];
+    match field {
+        Setting::Set(value) => Some(value),
+        Setting::Reset => Some(&wildcard),
+        Setting::NotSet => None,
+    }
+    .serialize(s)
+}
+
+#[derive(Clone, Default, Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Checked;
+
+#[derive(Clone, Default, Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Unchecked;
+
+/// Holds all the settings for an index. `T` can either be `Checked` if they represents settings
+/// whose validity is guaranteed, or `Unchecked` if they need to be validated. In the later case, a
+/// call to `check` will return a `Settings<Checked>` from a `Settings<Unchecked>`.
+#[derive(Debug, Clone, Default, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+#[serde(bound(serialize = "T: serde::Serialize", deserialize = "T: Deserialize<'static>"))]
+pub struct Settings<T> {
+    #[serde(
+        default,
+        serialize_with = "serialize_with_wildcard",
+        skip_serializing_if = "Setting::is_not_set"
+    )]
+    pub displayed_attributes: Setting<Vec<String>>,
+
+    #[serde(
+        default,
+        serialize_with = "serialize_with_wildcard",
+        skip_serializing_if = "Setting::is_not_set"
+    )]
+    pub searchable_attributes: Setting<Vec<String>>,
+
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub filterable_attributes: Setting<BTreeSet<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub sortable_attributes: Setting<BTreeSet<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub ranking_rules: Setting<Vec<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub stop_words: Setting<BTreeSet<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub synonyms: Setting<BTreeMap<String, Vec<String>>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub distinct_attribute: Setting<String>,
+
+    #[serde(skip)]
+    pub _kind: PhantomData<T>,
+}
+
+impl Settings<Checked> {
+    pub fn cleared() -> Settings<Checked> {
+        Settings {
+            displayed_attributes: Setting::Reset,
+            searchable_attributes: Setting::Reset,
+            filterable_attributes: Setting::Reset,
+            sortable_attributes: Setting::Reset,
+            ranking_rules: Setting::Reset,
+            stop_words: Setting::Reset,
+            synonyms: Setting::Reset,
+            distinct_attribute: Setting::Reset,
+            _kind: PhantomData,
+        }
+    }
+
+    pub fn into_unchecked(self) -> Settings<Unchecked> {
+        let Self {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes,
+            sortable_attributes,
+            ranking_rules,
+            stop_words,
+            synonyms,
+            distinct_attribute,
+            ..
+        } = self;
+
+        Settings {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes,
+            sortable_attributes,
+            ranking_rules,
+            stop_words,
+            synonyms,
+            distinct_attribute,
+            _kind: PhantomData,
+        }
+    }
+}
+
+impl Settings<Unchecked> {
+    pub fn check(self) -> Settings<Checked> {
+        let displayed_attributes = match self.displayed_attributes {
+            Setting::Set(fields) => {
+                if fields.iter().any(|f| f == "*") {
+                    Setting::Reset
+                } else {
+                    Setting::Set(fields)
+                }
+            }
+            otherwise => otherwise,
+        };
+
+        let searchable_attributes = match self.searchable_attributes {
+            Setting::Set(fields) => {
+                if fields.iter().any(|f| f == "*") {
+                    Setting::Reset
+                } else {
+                    Setting::Set(fields)
+                }
+            }
+            otherwise => otherwise,
+        };
+
+        Settings {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes: self.filterable_attributes,
+            sortable_attributes: self.sortable_attributes,
+            ranking_rules: self.ranking_rules,
+            stop_words: self.stop_words,
+            synonyms: self.synonyms,
+            distinct_attribute: self.distinct_attribute,
+            _kind: PhantomData,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+pub struct Facets {
+    pub level_group_size: Option<NonZeroUsize>,
+    pub min_level_size: Option<NonZeroUsize>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum Setting<T> {
+    Set(T),
+    Reset,
+    NotSet,
+}
+
+impl<T> Default for Setting<T> {
+    fn default() -> Self {
+        Self::NotSet
+    }
+}
+
+impl<T> Setting<T> {
+    pub fn map<U, F>(self, f: F) -> Setting<U>
+    where
+        F: FnOnce(T) -> U,
+    {
+        match self {
+            Setting::Set(t) => Setting::Set(f(t)),
+            Setting::Reset => Setting::Reset,
+            Setting::NotSet => Setting::NotSet,
+        }
+    }
+
+    pub fn set(self) -> Option<T> {
+        match self {
+            Self::Set(value) => Some(value),
+            _ => None,
+        }
+    }
+
+    pub const fn as_ref(&self) -> Setting<&T> {
+        match *self {
+            Self::Set(ref value) => Setting::Set(value),
+            Self::Reset => Setting::Reset,
+            Self::NotSet => Setting::NotSet,
+        }
+    }
+
+    pub const fn is_not_set(&self) -> bool {
+        matches!(self, Self::NotSet)
+    }
+}
+
+#[cfg(test)]
+impl<T: serde::Serialize> serde::Serialize for Setting<T> {
+    fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            Self::Set(value) => Some(value),
+            // Usually not_set isn't serialized by setting skip_serializing_if field attribute
+            Self::NotSet | Self::Reset => None,
+        }
+        .serialize(serializer)
+    }
+}
+
+impl<'de, T: Deserialize<'de>> Deserialize<'de> for Setting<T> {
+    fn deserialize<D>(deserializer: D) -> std::result::Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        Deserialize::deserialize(deserializer).map(|x| match x {
+            Some(x) => Self::Set(x),
+            None => Self::Reset, // Reset is forced by sending null value
+        })
+    }
+}

dump/src/reader/v3/updates.rs

@@ -0,0 +1,227 @@
+use std::fmt::Display;
+
+use serde::Deserialize;
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+use super::{Code, Settings, Unchecked};
+
+#[derive(Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct UpdateEntry {
+    pub uuid: Uuid,
+    pub update: UpdateStatus,
+}
+
+impl UpdateEntry {
+    pub fn is_finished(&self) -> bool {
+        match self.update {
+            UpdateStatus::Processed(_) | UpdateStatus::Aborted(_) | UpdateStatus::Failed(_) => true,
+            UpdateStatus::Processing(_) | UpdateStatus::Enqueued(_) => false,
+        }
+    }
+
+    pub fn get_content_uuid(&self) -> Option<&Uuid> {
+        match self.update.meta() {
+            Update::DocumentAddition { content_uuid, .. } => Some(content_uuid),
+            Update::DeleteDocuments(_) | Update::Settings(_) | Update::ClearDocuments => None,
+        }
+    }
+}
+
+#[derive(Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(tag = "status", rename_all = "camelCase")]
+pub enum UpdateStatus {
+    Processing(Processing),
+    Enqueued(Enqueued),
+    Processed(Processed),
+    Aborted(Aborted),
+    Failed(Failed),
+}
+
+impl UpdateStatus {
+    pub fn id(&self) -> u64 {
+        match self {
+            UpdateStatus::Processing(u) => u.id(),
+            UpdateStatus::Enqueued(u) => u.id(),
+            UpdateStatus::Processed(u) => u.id(),
+            UpdateStatus::Aborted(u) => u.id(),
+            UpdateStatus::Failed(u) => u.id(),
+        }
+    }
+
+    pub fn meta(&self) -> &Update {
+        match self {
+            UpdateStatus::Processing(u) => u.meta(),
+            UpdateStatus::Enqueued(u) => u.meta(),
+            UpdateStatus::Processed(u) => u.meta(),
+            UpdateStatus::Aborted(u) => u.meta(),
+            UpdateStatus::Failed(u) => u.meta(),
+        }
+    }
+
+    pub fn is_finished(&self) -> bool {
+        match self {
+            UpdateStatus::Processing(_) | UpdateStatus::Enqueued(_) => false,
+            UpdateStatus::Aborted(_) | UpdateStatus::Failed(_) | UpdateStatus::Processed(_) => true,
+        }
+    }
+
+    pub fn processed(&self) -> Option<&Processed> {
+        match self {
+            UpdateStatus::Processed(p) => Some(p),
+            _ => None,
+        }
+    }
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Enqueued {
+    pub update_id: u64,
+    pub meta: Update,
+    #[serde(with = "time::serde::rfc3339")]
+    pub enqueued_at: OffsetDateTime,
+}
+
+impl Enqueued {
+    pub fn meta(&self) -> &Update {
+        &self.meta
+    }
+
+    pub fn id(&self) -> u64 {
+        self.update_id
+    }
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Processed {
+    pub success: UpdateResult,
+    #[serde(with = "time::serde::rfc3339")]
+    pub processed_at: OffsetDateTime,
+    #[serde(flatten)]
+    pub from: Processing,
+}
+
+impl Processed {
+    pub fn id(&self) -> u64 {
+        self.from.id()
+    }
+
+    pub fn meta(&self) -> &Update {
+        self.from.meta()
+    }
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Processing {
+    #[serde(flatten)]
+    pub from: Enqueued,
+    #[serde(with = "time::serde::rfc3339")]
+    pub started_processing_at: OffsetDateTime,
+}
+
+impl Processing {
+    pub fn id(&self) -> u64 {
+        self.from.id()
+    }
+
+    pub fn meta(&self) -> &Update {
+        self.from.meta()
+    }
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Aborted {
+    #[serde(flatten)]
+    pub from: Enqueued,
+    #[serde(with = "time::serde::rfc3339")]
+    pub aborted_at: OffsetDateTime,
+}
+
+impl Aborted {
+    pub fn id(&self) -> u64 {
+        self.from.id()
+    }
+
+    pub fn meta(&self) -> &Update {
+        self.from.meta()
+    }
+}
+
+#[derive(Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub struct Failed {
+    #[serde(flatten)]
+    pub from: Processing,
+    pub msg: String,
+    pub code: Code,
+    #[serde(with = "time::serde::rfc3339")]
+    pub failed_at: OffsetDateTime,
+}
+
+impl Display for Failed {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.msg.fmt(f)
+    }
+}
+
+impl Failed {
+    pub fn id(&self) -> u64 {
+        self.from.id()
+    }
+
+    pub fn meta(&self) -> &Update {
+        self.from.meta()
+    }
+}
+
+#[allow(clippy::large_enum_variant)]
+#[derive(Debug, Clone, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum Update {
+    DeleteDocuments(Vec<String>),
+    DocumentAddition {
+        primary_key: Option<String>,
+        method: IndexDocumentsMethod,
+        content_uuid: Uuid,
+    },
+    Settings(Settings<Unchecked>),
+    ClearDocuments,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[non_exhaustive]
+pub enum IndexDocumentsMethod {
+    /// Replace the previous document with the new one,
+    /// removing all the already known attributes.
+    ReplaceDocuments,
+
+    /// Merge the previous version of the document with the new version,
+    /// replacing old attributes values with the new ones and add the new attributes.
+    UpdateDocuments,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum UpdateResult {
+    DocumentsAddition(DocumentAdditionResult),
+    DocumentDeletion { deleted: u64 },
+    Other,
+}
+
+#[derive(Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct DocumentAdditionResult {
+    pub nb_documents: usize,
+}

dump/src/reader/v4/errors.rs

@@ -0,0 +1,311 @@
+use std::fmt;
+
+use http::StatusCode;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, Eq)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "test-traits", derive(proptest_derive::Arbitrary))]
+pub struct ResponseError {
+    #[serde(skip)]
+    #[cfg_attr(feature = "test-traits", proptest(strategy = "strategy::status_code_strategy()"))]
+    pub code: StatusCode,
+    pub message: String,
+    #[serde(rename = "code")]
+    pub error_code: String,
+    #[serde(rename = "type")]
+    pub error_type: String,
+    #[serde(rename = "link")]
+    pub error_link: String,
+}
+
+impl ResponseError {
+    pub fn from_msg(message: String, code: Code) -> Self {
+        Self {
+            code: code.http(),
+            message,
+            error_code: code.err_code().error_name.to_string(),
+            error_type: code.type_(),
+            error_link: code.url(),
+        }
+    }
+}
+
+impl fmt::Display for ResponseError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.message.fmt(f)
+    }
+}
+
+impl std::error::Error for ResponseError {}
+
+impl<T> From<T> for ResponseError
+where
+    T: ErrorCode,
+{
+    fn from(other: T) -> Self {
+        Self {
+            code: other.http_status(),
+            message: other.to_string(),
+            error_code: other.error_name(),
+            error_type: other.error_type(),
+            error_link: other.error_url(),
+        }
+    }
+}
+
+pub trait ErrorCode: std::error::Error {
+    fn error_code(&self) -> Code;
+
+    /// returns the HTTP status code ascociated with the error
+    fn http_status(&self) -> StatusCode {
+        self.error_code().http()
+    }
+
+    /// returns the doc url ascociated with the error
+    fn error_url(&self) -> String {
+        self.error_code().url()
+    }
+
+    /// returns error name, used as error code
+    fn error_name(&self) -> String {
+        self.error_code().name()
+    }
+
+    /// return the error type
+    fn error_type(&self) -> String {
+        self.error_code().type_()
+    }
+}
+
+#[allow(clippy::enum_variant_names)]
+enum ErrorType {
+    InternalError,
+    InvalidRequestError,
+    AuthenticationError,
+}
+
+impl fmt::Display for ErrorType {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        use ErrorType::*;
+
+        match self {
+            InternalError => write!(f, "internal"),
+            InvalidRequestError => write!(f, "invalid_request"),
+            AuthenticationError => write!(f, "auth"),
+        }
+    }
+}
+
+#[derive(Serialize, Deserialize, Debug, Clone, Copy)]
+pub enum Code {
+    // index related error
+    CreateIndex,
+    IndexAlreadyExists,
+    IndexNotFound,
+    InvalidIndexUid,
+    InvalidMinWordLengthForTypo,
+
+    // invalid state error
+    InvalidState,
+    MissingPrimaryKey,
+    PrimaryKeyAlreadyPresent,
+
+    MaxFieldsLimitExceeded,
+    MissingDocumentId,
+    InvalidDocumentId,
+
+    Filter,
+    Sort,
+
+    BadParameter,
+    BadRequest,
+    DatabaseSizeLimitReached,
+    DocumentNotFound,
+    Internal,
+    InvalidGeoField,
+    InvalidRankingRule,
+    InvalidStore,
+    InvalidToken,
+    MissingAuthorizationHeader,
+    NoSpaceLeftOnDevice,
+    DumpNotFound,
+    TaskNotFound,
+    PayloadTooLarge,
+    RetrieveDocument,
+    SearchDocuments,
+    UnsupportedMediaType,
+
+    DumpAlreadyInProgress,
+    DumpProcessFailed,
+
+    InvalidContentType,
+    MissingContentType,
+    MalformedPayload,
+    MissingPayload,
+
+    ApiKeyNotFound,
+    MissingParameter,
+    InvalidApiKeyActions,
+    InvalidApiKeyIndexes,
+    InvalidApiKeyExpiresAt,
+    InvalidApiKeyDescription,
+
+    UnretrievableErrorCode,
+    MalformedDump,
+}
+
+impl Code {
+    /// ascociate a `Code` variant to the actual ErrCode
+    fn err_code(&self) -> ErrCode {
+        use Code::*;
+
+        match self {
+            // index related errors
+            // create index is thrown on internal error while creating an index.
+            CreateIndex => {
+                ErrCode::internal("index_creation_failed", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            IndexAlreadyExists => ErrCode::invalid("index_already_exists", StatusCode::CONFLICT),
+            // thrown when requesting an unexisting index
+            IndexNotFound => ErrCode::invalid("index_not_found", StatusCode::NOT_FOUND),
+            InvalidIndexUid => ErrCode::invalid("invalid_index_uid", StatusCode::BAD_REQUEST),
+
+            // invalid state error
+            InvalidState => ErrCode::internal("invalid_state", StatusCode::INTERNAL_SERVER_ERROR),
+            // thrown when no primary key has been set
+            MissingPrimaryKey => {
+                ErrCode::invalid("primary_key_inference_failed", StatusCode::BAD_REQUEST)
+            }
+            // error thrown when trying to set an already existing primary key
+            PrimaryKeyAlreadyPresent => {
+                ErrCode::invalid("index_primary_key_already_exists", StatusCode::BAD_REQUEST)
+            }
+            // invalid ranking rule
+            InvalidRankingRule => ErrCode::invalid("invalid_ranking_rule", StatusCode::BAD_REQUEST),
+
+            // invalid database
+            InvalidStore => {
+                ErrCode::internal("invalid_store_file", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+
+            // invalid document
+            MaxFieldsLimitExceeded => {
+                ErrCode::invalid("max_fields_limit_exceeded", StatusCode::BAD_REQUEST)
+            }
+            MissingDocumentId => ErrCode::invalid("missing_document_id", StatusCode::BAD_REQUEST),
+            InvalidDocumentId => ErrCode::invalid("invalid_document_id", StatusCode::BAD_REQUEST),
+
+            // error related to filters
+            Filter => ErrCode::invalid("invalid_filter", StatusCode::BAD_REQUEST),
+            // error related to sorts
+            Sort => ErrCode::invalid("invalid_sort", StatusCode::BAD_REQUEST),
+
+            BadParameter => ErrCode::invalid("bad_parameter", StatusCode::BAD_REQUEST),
+            BadRequest => ErrCode::invalid("bad_request", StatusCode::BAD_REQUEST),
+            DatabaseSizeLimitReached => {
+                ErrCode::internal("database_size_limit_reached", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            DocumentNotFound => ErrCode::invalid("document_not_found", StatusCode::NOT_FOUND),
+            Internal => ErrCode::internal("internal", StatusCode::INTERNAL_SERVER_ERROR),
+            InvalidGeoField => ErrCode::invalid("invalid_geo_field", StatusCode::BAD_REQUEST),
+            InvalidToken => ErrCode::authentication("invalid_api_key", StatusCode::FORBIDDEN),
+            MissingAuthorizationHeader => {
+                ErrCode::authentication("missing_authorization_header", StatusCode::UNAUTHORIZED)
+            }
+            TaskNotFound => ErrCode::invalid("task_not_found", StatusCode::NOT_FOUND),
+            DumpNotFound => ErrCode::invalid("dump_not_found", StatusCode::NOT_FOUND),
+            NoSpaceLeftOnDevice => {
+                ErrCode::internal("no_space_left_on_device", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            PayloadTooLarge => ErrCode::invalid("payload_too_large", StatusCode::PAYLOAD_TOO_LARGE),
+            RetrieveDocument => {
+                ErrCode::internal("unretrievable_document", StatusCode::BAD_REQUEST)
+            }
+            SearchDocuments => ErrCode::internal("search_error", StatusCode::BAD_REQUEST),
+            UnsupportedMediaType => {
+                ErrCode::invalid("unsupported_media_type", StatusCode::UNSUPPORTED_MEDIA_TYPE)
+            }
+
+            // error related to dump
+            DumpAlreadyInProgress => {
+                ErrCode::invalid("dump_already_processing", StatusCode::CONFLICT)
+            }
+            DumpProcessFailed => {
+                ErrCode::internal("dump_process_failed", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            MissingContentType => {
+                ErrCode::invalid("missing_content_type", StatusCode::UNSUPPORTED_MEDIA_TYPE)
+            }
+            MalformedPayload => ErrCode::invalid("malformed_payload", StatusCode::BAD_REQUEST),
+            InvalidContentType => {
+                ErrCode::invalid("invalid_content_type", StatusCode::UNSUPPORTED_MEDIA_TYPE)
+            }
+            MissingPayload => ErrCode::invalid("missing_payload", StatusCode::BAD_REQUEST),
+
+            // error related to keys
+            ApiKeyNotFound => ErrCode::invalid("api_key_not_found", StatusCode::NOT_FOUND),
+            MissingParameter => ErrCode::invalid("missing_parameter", StatusCode::BAD_REQUEST),
+            InvalidApiKeyActions => {
+                ErrCode::invalid("invalid_api_key_actions", StatusCode::BAD_REQUEST)
+            }
+            InvalidApiKeyIndexes => {
+                ErrCode::invalid("invalid_api_key_indexes", StatusCode::BAD_REQUEST)
+            }
+            InvalidApiKeyExpiresAt => {
+                ErrCode::invalid("invalid_api_key_expires_at", StatusCode::BAD_REQUEST)
+            }
+            InvalidApiKeyDescription => {
+                ErrCode::invalid("invalid_api_key_description", StatusCode::BAD_REQUEST)
+            }
+            InvalidMinWordLengthForTypo => {
+                ErrCode::invalid("invalid_min_word_length_for_typo", StatusCode::BAD_REQUEST)
+            }
+            UnretrievableErrorCode => {
+                ErrCode::invalid("unretrievable_error_code", StatusCode::BAD_REQUEST)
+            }
+            MalformedDump => ErrCode::invalid("malformed_dump", StatusCode::BAD_REQUEST),
+        }
+    }
+
+    /// return the HTTP status code ascociated with the `Code`
+    fn http(&self) -> StatusCode {
+        self.err_code().status_code
+    }
+
+    /// return error name, used as error code
+    fn name(&self) -> String {
+        self.err_code().error_name.to_string()
+    }
+
+    /// return the error type
+    fn type_(&self) -> String {
+        self.err_code().error_type.to_string()
+    }
+
+    /// return the doc url ascociated with the error
+    fn url(&self) -> String {
+        format!("https://docs.meilisearch.com/errors#{}", self.name())
+    }
+}
+
+/// Internal structure providing a convenient way to create error codes
+struct ErrCode {
+    status_code: StatusCode,
+    error_type: ErrorType,
+    error_name: &'static str,
+}
+
+impl ErrCode {
+    fn authentication(error_name: &'static str, status_code: StatusCode) -> ErrCode {
+        ErrCode { status_code, error_name, error_type: ErrorType::AuthenticationError }
+    }
+
+    fn internal(error_name: &'static str, status_code: StatusCode) -> ErrCode {
+        ErrCode { status_code, error_name, error_type: ErrorType::InternalError }
+    }
+
+    fn invalid(error_name: &'static str, status_code: StatusCode) -> ErrCode {
+        ErrCode { status_code, error_name, error_type: ErrorType::InvalidRequestError }
+    }
+}

dump/src/reader/v4/keys.rs

@@ -0,0 +1,77 @@
+use serde::Deserialize;
+use time::OffsetDateTime;
+
+pub const KEY_ID_LENGTH: usize = 8;
+pub type KeyId = [u8; KEY_ID_LENGTH];
+
+#[derive(Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Key {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub description: Option<String>,
+    pub id: KeyId,
+    pub actions: Vec<Action>,
+    pub indexes: Vec<String>,
+    #[serde(with = "time::serde::rfc3339::option")]
+    pub expires_at: Option<OffsetDateTime>,
+    #[serde(with = "time::serde::rfc3339")]
+    pub created_at: OffsetDateTime,
+    #[serde(with = "time::serde::rfc3339")]
+    pub updated_at: OffsetDateTime,
+}
+
+#[derive(Copy, Clone, Deserialize, Debug, Eq, PartialEq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[repr(u8)]
+pub enum Action {
+    #[serde(rename = "*")]
+    All = 0,
+    #[serde(rename = "search")]
+    Search = actions::SEARCH,
+    #[serde(rename = "documents.add")]
+    DocumentsAdd = actions::DOCUMENTS_ADD,
+    #[serde(rename = "documents.get")]
+    DocumentsGet = actions::DOCUMENTS_GET,
+    #[serde(rename = "documents.delete")]
+    DocumentsDelete = actions::DOCUMENTS_DELETE,
+    #[serde(rename = "indexes.create")]
+    IndexesAdd = actions::INDEXES_CREATE,
+    #[serde(rename = "indexes.get")]
+    IndexesGet = actions::INDEXES_GET,
+    #[serde(rename = "indexes.update")]
+    IndexesUpdate = actions::INDEXES_UPDATE,
+    #[serde(rename = "indexes.delete")]
+    IndexesDelete = actions::INDEXES_DELETE,
+    #[serde(rename = "tasks.get")]
+    TasksGet = actions::TASKS_GET,
+    #[serde(rename = "settings.get")]
+    SettingsGet = actions::SETTINGS_GET,
+    #[serde(rename = "settings.update")]
+    SettingsUpdate = actions::SETTINGS_UPDATE,
+    #[serde(rename = "stats.get")]
+    StatsGet = actions::STATS_GET,
+    #[serde(rename = "dumps.create")]
+    DumpsCreate = actions::DUMPS_CREATE,
+    #[serde(rename = "dumps.get")]
+    DumpsGet = actions::DUMPS_GET,
+    #[serde(rename = "version")]
+    Version = actions::VERSION,
+}
+
+pub mod actions {
+    pub const SEARCH: u8 = 1;
+    pub const DOCUMENTS_ADD: u8 = 2;
+    pub const DOCUMENTS_GET: u8 = 3;
+    pub const DOCUMENTS_DELETE: u8 = 4;
+    pub const INDEXES_CREATE: u8 = 5;
+    pub const INDEXES_GET: u8 = 6;
+    pub const INDEXES_UPDATE: u8 = 7;
+    pub const INDEXES_DELETE: u8 = 8;
+    pub const TASKS_GET: u8 = 9;
+    pub const SETTINGS_GET: u8 = 10;
+    pub const SETTINGS_UPDATE: u8 = 11;
+    pub const STATS_GET: u8 = 12;
+    pub const DUMPS_CREATE: u8 = 13;
+    pub const DUMPS_GET: u8 = 14;
+    pub const VERSION: u8 = 15;
+}

dump/src/reader/v4/meta.rs

@@ -0,0 +1,139 @@
+use std::fmt::{self, Display, Formatter};
+use std::marker::PhantomData;
+use std::str::FromStr;
+
+use serde::de::Visitor;
+use serde::{Deserialize, Deserializer};
+use uuid::Uuid;
+
+use super::settings::{Settings, Unchecked};
+
+#[derive(Deserialize, Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct IndexUuid {
+    pub uid: String,
+    pub index_meta: IndexMeta,
+}
+
+#[derive(Deserialize, Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct IndexMeta {
+    pub uuid: Uuid,
+    pub creation_task_id: usize,
+}
+
+// There is one in each indexes under `meta.json`.
+#[derive(Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct DumpMeta {
+    pub settings: Settings<Unchecked>,
+    pub primary_key: Option<String>,
+}
+
+#[derive(Deserialize, Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct IndexUid(pub String);
+
+impl TryFrom<String> for IndexUid {
+    type Error = IndexUidFormatError;
+
+    fn try_from(uid: String) -> Result<Self, Self::Error> {
+        if !uid.chars().all(|x| x.is_ascii_alphanumeric() || x == '-' || x == '_')
+            || uid.is_empty()
+            || uid.len() > 400
+        {
+            Err(IndexUidFormatError { invalid_uid: uid })
+        } else {
+            Ok(IndexUid(uid))
+        }
+    }
+}
+
+impl FromStr for IndexUid {
+    type Err = IndexUidFormatError;
+
+    fn from_str(uid: &str) -> Result<IndexUid, IndexUidFormatError> {
+        uid.to_string().try_into()
+    }
+}
+
+impl From<IndexUid> for String {
+    fn from(uid: IndexUid) -> Self {
+        uid.into_inner()
+    }
+}
+
+#[derive(Debug)]
+pub struct IndexUidFormatError {
+    pub invalid_uid: String,
+}
+
+impl Display for IndexUidFormatError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        write!(
+            f,
+            "invalid index uid `{}`, the uid must be an integer \
+            or a string containing only alphanumeric characters \
+            a-z A-Z 0-9, hyphens - and underscores _.",
+            self.invalid_uid,
+        )
+    }
+}
+
+impl std::error::Error for IndexUidFormatError {}
+
+/// A type that tries to match either a star (*) or
+/// any other thing that implements `FromStr`.
+#[derive(Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum StarOr<T> {
+    Star,
+    Other(T),
+}
+
+impl<'de, T, E> Deserialize<'de> for StarOr<T>
+where
+    T: FromStr<Err = E>,
+    E: Display,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        /// Serde can't differentiate between `StarOr::Star` and `StarOr::Other` without a tag.
+        /// Simply using `#[serde(untagged)]` + `#[serde(rename="*")]` will lead to attempting to
+        /// deserialize everything as a `StarOr::Other`, including "*".
+        /// [`#[serde(other)]`](https://serde.rs/variant-attrs.html#other) might have helped but is
+        /// not supported on untagged enums.
+        struct StarOrVisitor<T>(PhantomData<T>);
+
+        impl<'de, T, FE> Visitor<'de> for StarOrVisitor<T>
+        where
+            T: FromStr<Err = FE>,
+            FE: Display,
+        {
+            type Value = StarOr<T>;
+
+            fn expecting(&self, formatter: &mut Formatter) -> std::fmt::Result {
+                formatter.write_str("a string")
+            }
+
+            fn visit_str<SE>(self, v: &str) -> Result<Self::Value, SE>
+            where
+                SE: serde::de::Error,
+            {
+                match v {
+                    "*" => Ok(StarOr::Star),
+                    v => {
+                        let other = FromStr::from_str(v).map_err(|e: T::Err| {
+                            SE::custom(format!("Invalid `other` value: {}", e))
+                        })?;
+                        Ok(StarOr::Other(other))
+                    }
+                }
+            }
+        }
+
+        deserializer.deserialize_str(StarOrVisitor(PhantomData))
+    }
+}

dump/src/reader/v4/mod.rs

@@ -0,0 +1,307 @@
+use std::fs::{self, File};
+use std::io::{BufRead, BufReader, ErrorKind};
+use std::path::Path;
+
+use serde::{Deserialize, Serialize};
+use tempfile::TempDir;
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+pub mod errors;
+pub mod keys;
+pub mod meta;
+pub mod settings;
+pub mod tasks;
+
+use self::meta::{DumpMeta, IndexUuid};
+use super::compat::v4_to_v5::CompatV4ToV5;
+use crate::{Error, IndexMetadata, Result, Version};
+
+pub type Document = serde_json::Map<String, serde_json::Value>;
+pub type Settings<T> = settings::Settings<T>;
+pub type Checked = settings::Checked;
+pub type Unchecked = settings::Unchecked;
+
+pub type Task = tasks::Task;
+pub type Key = keys::Key;
+
+// everything related to the settings
+pub type Setting<T> = settings::Setting<T>;
+
+// everything related to the api keys
+pub type Action = keys::Action;
+
+// everything related to the errors
+pub type ResponseError = errors::ResponseError;
+pub type Code = errors::Code;
+
+#[derive(Serialize, Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct Metadata {
+    db_version: String,
+    index_db_size: usize,
+    update_db_size: usize,
+    #[serde(with = "time::serde::rfc3339")]
+    dump_date: OffsetDateTime,
+}
+
+pub struct V4Reader {
+    dump: TempDir,
+    metadata: Metadata,
+    tasks: BufReader<File>,
+    keys: BufReader<File>,
+    index_uuid: Vec<IndexUuid>,
+}
+
+impl V4Reader {
+    pub fn open(dump: TempDir) -> Result<Self> {
+        let meta_file = fs::read(dump.path().join("metadata.json"))?;
+        let metadata = serde_json::from_reader(&*meta_file)?;
+        let index_uuid = File::open(dump.path().join("index_uuids/data.jsonl"))?;
+        let index_uuid = BufReader::new(index_uuid);
+        let index_uuid = index_uuid
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) })
+            .collect::<Result<Vec<_>>>()?;
+
+        Ok(V4Reader {
+            metadata,
+            tasks: BufReader::new(
+                File::open(dump.path().join("updates").join("data.jsonl")).unwrap(),
+            ),
+            keys: BufReader::new(File::open(dump.path().join("keys"))?),
+            index_uuid,
+            dump,
+        })
+    }
+
+    pub fn to_v5(self) -> CompatV4ToV5 {
+        CompatV4ToV5::new(self)
+    }
+
+    pub fn version(&self) -> Version {
+        Version::V4
+    }
+
+    pub fn date(&self) -> Option<OffsetDateTime> {
+        Some(self.metadata.dump_date)
+    }
+
+    pub fn instance_uid(&self) -> Result<Option<Uuid>> {
+        match fs::read_to_string(self.dump.path().join("instance-uid")) {
+            Ok(uuid) => Ok(Some(Uuid::parse_str(&uuid)?)),
+            Err(e) if e.kind() == ErrorKind::NotFound => Ok(None),
+            Err(e) => Err(e.into()),
+        }
+    }
+
+    pub fn indexes(&self) -> Result<impl Iterator<Item = Result<V4IndexReader>> + '_> {
+        Ok(self.index_uuid.iter().map(|index| -> Result<_> {
+            V4IndexReader::new(
+                index.uid.clone(),
+                &self.dump.path().join("indexes").join(index.index_meta.uuid.to_string()),
+            )
+        }))
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Box<dyn Iterator<Item = Result<(Task, Option<Box<super::UpdateFile>>)>> + '_> {
+        Box::new((&mut self.tasks).lines().map(|line| -> Result<_> {
+            let task: Task = serde_json::from_str(&line?)?;
+            if !task.is_finished() {
+                if let Some(uuid) = task.get_content_uuid() {
+                    let update_file_path = self
+                        .dump
+                        .path()
+                        .join("updates")
+                        .join("updates_files")
+                        .join(uuid.to_string());
+                    Ok((
+                        task,
+                        Some(
+                            Box::new(UpdateFile::new(&update_file_path)?) as Box<super::UpdateFile>
+                        ),
+                    ))
+                } else {
+                    Ok((task, None))
+                }
+            } else {
+                Ok((task, None))
+            }
+        }))
+    }
+
+    pub fn keys(&mut self) -> Box<dyn Iterator<Item = Result<Key>> + '_> {
+        Box::new(
+            (&mut self.keys).lines().map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) }),
+        )
+    }
+}
+
+pub struct V4IndexReader {
+    metadata: IndexMetadata,
+    settings: Settings<Checked>,
+
+    documents: BufReader<File>,
+}
+
+impl V4IndexReader {
+    pub fn new(name: String, path: &Path) -> Result<Self> {
+        let meta = File::open(path.join("meta.json"))?;
+        let meta: DumpMeta = serde_json::from_reader(meta)?;
+
+        let metadata = IndexMetadata {
+            uid: name,
+            primary_key: meta.primary_key,
+            // FIXME: Iterate over the whole task queue to find the creation and last update date.
+            created_at: OffsetDateTime::now_utc(),
+            updated_at: OffsetDateTime::now_utc(),
+        };
+
+        let ret = V4IndexReader {
+            metadata,
+            settings: meta.settings.check(),
+            documents: BufReader::new(File::open(path.join("documents.jsonl"))?),
+        };
+
+        Ok(ret)
+    }
+
+    pub fn metadata(&self) -> &IndexMetadata {
+        &self.metadata
+    }
+
+    pub fn documents(&mut self) -> Result<impl Iterator<Item = Result<Document>> + '_> {
+        Ok((&mut self.documents)
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) }))
+    }
+
+    pub fn settings(&mut self) -> Result<Settings<Checked>> {
+        Ok(self.settings.clone())
+    }
+}
+
+pub struct UpdateFile {
+    reader: BufReader<File>,
+}
+
+impl UpdateFile {
+    fn new(path: &Path) -> Result<Self> {
+        Ok(UpdateFile { reader: BufReader::new(File::open(path)?) })
+    }
+}
+
+impl Iterator for UpdateFile {
+    type Item = Result<Document>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        (&mut self.reader)
+            .lines()
+            .map(|line| {
+                line.map_err(Error::from)
+                    .and_then(|line| serde_json::from_str(&line).map_err(Error::from))
+            })
+            .next()
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::BufReader;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use tempfile::TempDir;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn read_dump_v4() {
+        let dump = File::open("tests/assets/v4.dump").unwrap();
+        let dir = TempDir::new().unwrap();
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(dir.path()).unwrap();
+
+        let mut dump = V4Reader::open(dir).unwrap();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-06 12:53:49.131989609 +00:00:00");
+        insta::assert_display_snapshot!(dump.instance_uid().unwrap().unwrap(), @"9e15e977-f2ae-4761-943f-1eaf75fd736d");
+
+        // tasks
+        let tasks = dump.tasks().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, mut update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"f4efacbea0c1a4400873f4b2ee33f975");
+        assert_eq!(update_files.len(), 10);
+        assert!(update_files[0].is_some()); // the enqueued document addition
+        assert!(update_files[1..].iter().all(|u| u.is_none())); // everything already processed
+
+        let update_file = update_files.remove(0).unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(update_file), @"7b8889539b669c7b9ddba448bafa385d");
+
+        // keys
+        let keys = dump.keys().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys, { "[].uid" => "[uuid]" }), @"9240300dca8f962cdf58359ef4c76f09");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"65b139c6b9fc251e187073c8557803e2");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"b01c8371aea4c7171af0d4d846a2bdca");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"06aa1988493485d9b2cda7c751e6bb15");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 110);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"786022a66ecb992c8a2a60fee070a5ab");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"7d722fc2629eaa45032ed3deb0c9b4ce");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/v4/settings.rs

@@ -0,0 +1,261 @@
+use std::collections::{BTreeMap, BTreeSet};
+use std::marker::PhantomData;
+use std::num::NonZeroUsize;
+
+use serde::{Deserialize, Deserializer};
+
+#[cfg(test)]
+fn serialize_with_wildcard<S>(
+    field: &Setting<Vec<String>>,
+    s: S,
+) -> std::result::Result<S::Ok, S::Error>
+where
+    S: serde::Serializer,
+{
+    use serde::Serialize;
+
+    let wildcard = vec!["*".to_string()];
+    match field {
+        Setting::Set(value) => Some(value),
+        Setting::Reset => Some(&wildcard),
+        Setting::NotSet => None,
+    }
+    .serialize(s)
+}
+
+#[derive(Clone, Default, Debug, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Checked;
+
+#[derive(Clone, Default, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Unchecked;
+
+#[derive(Debug, Clone, Default, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+pub struct MinWordSizeTyposSetting {
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub one_typo: Setting<u8>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub two_typos: Setting<u8>,
+}
+
+#[derive(Debug, Clone, Default, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+pub struct TypoSettings {
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub enabled: Setting<bool>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub min_word_size_for_typos: Setting<MinWordSizeTyposSetting>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub disable_on_words: Setting<BTreeSet<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub disable_on_attributes: Setting<BTreeSet<String>>,
+}
+/// Holds all the settings for an index. `T` can either be `Checked` if they represents settings
+/// whose validity is guaranteed, or `Unchecked` if they need to be validated. In the later case, a
+/// call to `check` will return a `Settings<Checked>` from a `Settings<Unchecked>`.
+#[derive(Debug, Clone, Default, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+#[serde(bound(serialize = "T: serde::Serialize", deserialize = "T: Deserialize<'static>"))]
+pub struct Settings<T> {
+    #[serde(
+        default,
+        serialize_with = "serialize_with_wildcard",
+        skip_serializing_if = "Setting::is_not_set"
+    )]
+    pub displayed_attributes: Setting<Vec<String>>,
+
+    #[serde(
+        default,
+        serialize_with = "serialize_with_wildcard",
+        skip_serializing_if = "Setting::is_not_set"
+    )]
+    pub searchable_attributes: Setting<Vec<String>>,
+
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub filterable_attributes: Setting<BTreeSet<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub sortable_attributes: Setting<BTreeSet<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub ranking_rules: Setting<Vec<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub stop_words: Setting<BTreeSet<String>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub synonyms: Setting<BTreeMap<String, Vec<String>>>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub distinct_attribute: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub typo_tolerance: Setting<TypoSettings>,
+
+    #[serde(skip)]
+    pub _kind: PhantomData<T>,
+}
+
+impl Settings<Checked> {
+    pub fn cleared() -> Settings<Checked> {
+        Settings {
+            displayed_attributes: Setting::Reset,
+            searchable_attributes: Setting::Reset,
+            filterable_attributes: Setting::Reset,
+            sortable_attributes: Setting::Reset,
+            ranking_rules: Setting::Reset,
+            stop_words: Setting::Reset,
+            synonyms: Setting::Reset,
+            distinct_attribute: Setting::Reset,
+            typo_tolerance: Setting::Reset,
+            _kind: PhantomData,
+        }
+    }
+
+    pub fn into_unchecked(self) -> Settings<Unchecked> {
+        let Self {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes,
+            sortable_attributes,
+            ranking_rules,
+            stop_words,
+            synonyms,
+            distinct_attribute,
+            typo_tolerance,
+            ..
+        } = self;
+
+        Settings {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes,
+            sortable_attributes,
+            ranking_rules,
+            stop_words,
+            synonyms,
+            distinct_attribute,
+            typo_tolerance,
+            _kind: PhantomData,
+        }
+    }
+}
+
+impl Settings<Unchecked> {
+    pub fn check(self) -> Settings<Checked> {
+        let displayed_attributes = match self.displayed_attributes {
+            Setting::Set(fields) => {
+                if fields.iter().any(|f| f == "*") {
+                    Setting::Reset
+                } else {
+                    Setting::Set(fields)
+                }
+            }
+            otherwise => otherwise,
+        };
+
+        let searchable_attributes = match self.searchable_attributes {
+            Setting::Set(fields) => {
+                if fields.iter().any(|f| f == "*") {
+                    Setting::Reset
+                } else {
+                    Setting::Set(fields)
+                }
+            }
+            otherwise => otherwise,
+        };
+
+        Settings {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes: self.filterable_attributes,
+            sortable_attributes: self.sortable_attributes,
+            ranking_rules: self.ranking_rules,
+            stop_words: self.stop_words,
+            synonyms: self.synonyms,
+            distinct_attribute: self.distinct_attribute,
+            typo_tolerance: self.typo_tolerance,
+            _kind: PhantomData,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+pub struct Facets {
+    pub level_group_size: Option<NonZeroUsize>,
+    pub min_level_size: Option<NonZeroUsize>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Copy)]
+pub enum Setting<T> {
+    Set(T),
+    Reset,
+    NotSet,
+}
+
+impl<T> Default for Setting<T> {
+    fn default() -> Self {
+        Self::NotSet
+    }
+}
+
+impl<T> Setting<T> {
+    pub fn set(self) -> Option<T> {
+        match self {
+            Self::Set(value) => Some(value),
+            _ => None,
+        }
+    }
+
+    pub const fn as_ref(&self) -> Setting<&T> {
+        match *self {
+            Self::Set(ref value) => Setting::Set(value),
+            Self::Reset => Setting::Reset,
+            Self::NotSet => Setting::NotSet,
+        }
+    }
+
+    pub const fn is_not_set(&self) -> bool {
+        matches!(self, Self::NotSet)
+    }
+
+    /// If `Self` is `Reset`, then map self to `Set` with the provided `val`.
+    pub fn or_reset(self, val: T) -> Self {
+        match self {
+            Self::Reset => Self::Set(val),
+            otherwise => otherwise,
+        }
+    }
+}
+
+#[cfg(test)]
+impl<T: serde::Serialize> serde::Serialize for Setting<T> {
+    fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            Self::Set(value) => Some(value),
+            // Usually not_set isn't serialized by setting skip_serializing_if field attribute
+            Self::NotSet | Self::Reset => None,
+        }
+        .serialize(serializer)
+    }
+}
+
+impl<'de, T: Deserialize<'de>> Deserialize<'de> for Setting<T> {
+    fn deserialize<D>(deserializer: D) -> std::result::Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        Deserialize::deserialize(deserializer).map(|x| match x {
+            Some(x) => Self::Set(x),
+            None => Self::Reset, // Reset is forced by sending null value
+        })
+    }
+}

dump/src/reader/v4/tasks.rs

@@ -0,0 +1,135 @@
+use serde::Deserialize;
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+use super::errors::ResponseError;
+use super::meta::IndexUid;
+use super::settings::{Settings, Unchecked};
+
+pub type TaskId = u32;
+pub type BatchId = u32;
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Task {
+    pub id: TaskId,
+    pub index_uid: IndexUid,
+    pub content: TaskContent,
+    pub events: Vec<TaskEvent>,
+}
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[allow(clippy::large_enum_variant)]
+pub enum TaskContent {
+    DocumentAddition {
+        content_uuid: Uuid,
+        merge_strategy: IndexDocumentsMethod,
+        primary_key: Option<String>,
+        documents_count: usize,
+        allow_index_creation: bool,
+    },
+    DocumentDeletion(DocumentDeletion),
+    SettingsUpdate {
+        settings: Settings<Unchecked>,
+        /// Indicates whether the task was a deletion
+        is_deletion: bool,
+        allow_index_creation: bool,
+    },
+    IndexDeletion,
+    IndexCreation {
+        primary_key: Option<String>,
+    },
+    IndexUpdate {
+        primary_key: Option<String>,
+    },
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum IndexDocumentsMethod {
+    /// Replace the previous document with the new one,
+    /// removing all the already known attributes.
+    ReplaceDocuments,
+
+    /// Merge the previous version of the document with the new version,
+    /// replacing old attributes values with the new ones and add the new attributes.
+    UpdateDocuments,
+}
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum DocumentDeletion {
+    Clear,
+    Ids(Vec<String>),
+}
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum TaskEvent {
+    Created(#[serde(with = "time::serde::rfc3339")] OffsetDateTime),
+    Batched {
+        #[serde(with = "time::serde::rfc3339")]
+        timestamp: OffsetDateTime,
+        batch_id: BatchId,
+    },
+    Processing(#[serde(with = "time::serde::rfc3339")] OffsetDateTime),
+    Succeded {
+        result: TaskResult,
+        #[serde(with = "time::serde::rfc3339")]
+        timestamp: OffsetDateTime,
+    },
+    Failed {
+        error: ResponseError,
+        #[serde(with = "time::serde::rfc3339")]
+        timestamp: OffsetDateTime,
+    },
+}
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum TaskResult {
+    DocumentAddition { indexed_documents: u64 },
+    DocumentDeletion { deleted_documents: u64 },
+    ClearAll { deleted_documents: u64 },
+    Other,
+}
+
+impl Task {
+    /// Return true when a task is finished.
+    /// A task is finished when its last state is either `Succeeded` or `Failed`.
+    pub fn is_finished(&self) -> bool {
+        self.events.last().map_or(false, |event| {
+            matches!(event, TaskEvent::Succeded { .. } | TaskEvent::Failed { .. })
+        })
+    }
+
+    /// Return the content_uuid of the `Task` if there is one.
+    pub fn get_content_uuid(&self) -> Option<Uuid> {
+        match self {
+            Task { content: TaskContent::DocumentAddition { content_uuid, .. }, .. } => {
+                Some(*content_uuid)
+            }
+            _ => None,
+        }
+    }
+}
+
+impl IndexUid {
+    pub fn into_inner(self) -> String {
+        self.0
+    }
+
+    /// Return a reference over the inner str.
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+}
+
+impl std::ops::Deref for IndexUid {
+    type Target = str;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}

dump/src/reader/v5/errors.rs

@@ -0,0 +1,272 @@
+use std::fmt;
+
+use http::StatusCode;
+use serde::Deserialize;
+
+#[derive(Debug, Deserialize, Clone, PartialEq, Eq)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "test-traits", derive(proptest_derive::Arbitrary))]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct ResponseError {
+    #[serde(skip)]
+    code: StatusCode,
+
+    pub message: String,
+    #[serde(rename = "code")]
+    pub error_code: String,
+    #[serde(rename = "type")]
+    pub error_type: String,
+    #[serde(rename = "link")]
+    pub error_link: String,
+}
+
+impl ResponseError {
+    pub fn from_msg(message: String, code: Code) -> Self {
+        Self {
+            code: code.http(),
+            message,
+            error_code: code.err_code().error_name.to_string(),
+            error_type: code.type_(),
+            error_link: code.url(),
+        }
+    }
+}
+
+#[derive(Deserialize, Debug, Clone, Copy)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum Code {
+    // index related error
+    CreateIndex,
+    IndexAlreadyExists,
+    IndexNotFound,
+    InvalidIndexUid,
+    InvalidMinWordLengthForTypo,
+
+    // invalid state error
+    InvalidState,
+    MissingPrimaryKey,
+    PrimaryKeyAlreadyPresent,
+
+    MaxFieldsLimitExceeded,
+    MissingDocumentId,
+    InvalidDocumentId,
+
+    Filter,
+    Sort,
+
+    BadParameter,
+    BadRequest,
+    DatabaseSizeLimitReached,
+    DocumentNotFound,
+    Internal,
+    InvalidGeoField,
+    InvalidRankingRule,
+    InvalidStore,
+    InvalidToken,
+    MissingAuthorizationHeader,
+    NoSpaceLeftOnDevice,
+    DumpNotFound,
+    TaskNotFound,
+    PayloadTooLarge,
+    RetrieveDocument,
+    SearchDocuments,
+    UnsupportedMediaType,
+
+    DumpAlreadyInProgress,
+    DumpProcessFailed,
+
+    InvalidContentType,
+    MissingContentType,
+    MalformedPayload,
+    MissingPayload,
+
+    ApiKeyNotFound,
+    MissingParameter,
+    InvalidApiKeyActions,
+    InvalidApiKeyIndexes,
+    InvalidApiKeyExpiresAt,
+    InvalidApiKeyDescription,
+    InvalidApiKeyName,
+    InvalidApiKeyUid,
+    ImmutableField,
+    ApiKeyAlreadyExists,
+
+    UnretrievableErrorCode,
+}
+
+impl Code {
+    /// associate a `Code` variant to the actual ErrCode
+    fn err_code(&self) -> ErrCode {
+        use Code::*;
+
+        match self {
+            // index related errors
+            // create index is thrown on internal error while creating an index.
+            CreateIndex => {
+                ErrCode::internal("index_creation_failed", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            IndexAlreadyExists => ErrCode::invalid("index_already_exists", StatusCode::CONFLICT),
+            // thrown when requesting an unexisting index
+            IndexNotFound => ErrCode::invalid("index_not_found", StatusCode::NOT_FOUND),
+            InvalidIndexUid => ErrCode::invalid("invalid_index_uid", StatusCode::BAD_REQUEST),
+
+            // invalid state error
+            InvalidState => ErrCode::internal("invalid_state", StatusCode::INTERNAL_SERVER_ERROR),
+            // thrown when no primary key has been set
+            MissingPrimaryKey => {
+                ErrCode::invalid("primary_key_inference_failed", StatusCode::BAD_REQUEST)
+            }
+            // error thrown when trying to set an already existing primary key
+            PrimaryKeyAlreadyPresent => {
+                ErrCode::invalid("index_primary_key_already_exists", StatusCode::BAD_REQUEST)
+            }
+            // invalid ranking rule
+            InvalidRankingRule => ErrCode::invalid("invalid_ranking_rule", StatusCode::BAD_REQUEST),
+
+            // invalid database
+            InvalidStore => {
+                ErrCode::internal("invalid_store_file", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+
+            // invalid document
+            MaxFieldsLimitExceeded => {
+                ErrCode::invalid("max_fields_limit_exceeded", StatusCode::BAD_REQUEST)
+            }
+            MissingDocumentId => ErrCode::invalid("missing_document_id", StatusCode::BAD_REQUEST),
+            InvalidDocumentId => ErrCode::invalid("invalid_document_id", StatusCode::BAD_REQUEST),
+
+            // error related to filters
+            Filter => ErrCode::invalid("invalid_filter", StatusCode::BAD_REQUEST),
+            // error related to sorts
+            Sort => ErrCode::invalid("invalid_sort", StatusCode::BAD_REQUEST),
+
+            BadParameter => ErrCode::invalid("bad_parameter", StatusCode::BAD_REQUEST),
+            BadRequest => ErrCode::invalid("bad_request", StatusCode::BAD_REQUEST),
+            DatabaseSizeLimitReached => {
+                ErrCode::internal("database_size_limit_reached", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            DocumentNotFound => ErrCode::invalid("document_not_found", StatusCode::NOT_FOUND),
+            Internal => ErrCode::internal("internal", StatusCode::INTERNAL_SERVER_ERROR),
+            InvalidGeoField => ErrCode::invalid("invalid_geo_field", StatusCode::BAD_REQUEST),
+            InvalidToken => ErrCode::authentication("invalid_api_key", StatusCode::FORBIDDEN),
+            MissingAuthorizationHeader => {
+                ErrCode::authentication("missing_authorization_header", StatusCode::UNAUTHORIZED)
+            }
+            TaskNotFound => ErrCode::invalid("task_not_found", StatusCode::NOT_FOUND),
+            DumpNotFound => ErrCode::invalid("dump_not_found", StatusCode::NOT_FOUND),
+            NoSpaceLeftOnDevice => {
+                ErrCode::internal("no_space_left_on_device", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            PayloadTooLarge => ErrCode::invalid("payload_too_large", StatusCode::PAYLOAD_TOO_LARGE),
+            RetrieveDocument => {
+                ErrCode::internal("unretrievable_document", StatusCode::BAD_REQUEST)
+            }
+            SearchDocuments => ErrCode::internal("search_error", StatusCode::BAD_REQUEST),
+            UnsupportedMediaType => {
+                ErrCode::invalid("unsupported_media_type", StatusCode::UNSUPPORTED_MEDIA_TYPE)
+            }
+
+            // error related to dump
+            DumpAlreadyInProgress => {
+                ErrCode::invalid("dump_already_processing", StatusCode::CONFLICT)
+            }
+            DumpProcessFailed => {
+                ErrCode::internal("dump_process_failed", StatusCode::INTERNAL_SERVER_ERROR)
+            }
+            MissingContentType => {
+                ErrCode::invalid("missing_content_type", StatusCode::UNSUPPORTED_MEDIA_TYPE)
+            }
+            MalformedPayload => ErrCode::invalid("malformed_payload", StatusCode::BAD_REQUEST),
+            InvalidContentType => {
+                ErrCode::invalid("invalid_content_type", StatusCode::UNSUPPORTED_MEDIA_TYPE)
+            }
+            MissingPayload => ErrCode::invalid("missing_payload", StatusCode::BAD_REQUEST),
+
+            // error related to keys
+            ApiKeyNotFound => ErrCode::invalid("api_key_not_found", StatusCode::NOT_FOUND),
+            MissingParameter => ErrCode::invalid("missing_parameter", StatusCode::BAD_REQUEST),
+            InvalidApiKeyActions => {
+                ErrCode::invalid("invalid_api_key_actions", StatusCode::BAD_REQUEST)
+            }
+            InvalidApiKeyIndexes => {
+                ErrCode::invalid("invalid_api_key_indexes", StatusCode::BAD_REQUEST)
+            }
+            InvalidApiKeyExpiresAt => {
+                ErrCode::invalid("invalid_api_key_expires_at", StatusCode::BAD_REQUEST)
+            }
+            InvalidApiKeyDescription => {
+                ErrCode::invalid("invalid_api_key_description", StatusCode::BAD_REQUEST)
+            }
+            InvalidApiKeyName => ErrCode::invalid("invalid_api_key_name", StatusCode::BAD_REQUEST),
+            InvalidApiKeyUid => ErrCode::invalid("invalid_api_key_uid", StatusCode::BAD_REQUEST),
+            ApiKeyAlreadyExists => ErrCode::invalid("api_key_already_exists", StatusCode::CONFLICT),
+            ImmutableField => ErrCode::invalid("immutable_field", StatusCode::BAD_REQUEST),
+            InvalidMinWordLengthForTypo => {
+                ErrCode::invalid("invalid_min_word_length_for_typo", StatusCode::BAD_REQUEST)
+            }
+            UnretrievableErrorCode => {
+                ErrCode::invalid("unretrievable_error_code", StatusCode::BAD_REQUEST)
+            }
+        }
+    }
+
+    /// return the HTTP status code associated with the `Code`
+    fn http(&self) -> StatusCode {
+        self.err_code().status_code
+    }
+
+    /// return error name, used as error code
+    fn name(&self) -> String {
+        self.err_code().error_name.to_string()
+    }
+
+    /// return the error type
+    fn type_(&self) -> String {
+        self.err_code().error_type.to_string()
+    }
+
+    /// return the doc url associated with the error
+    fn url(&self) -> String {
+        format!("https://docs.meilisearch.com/errors#{}", self.name())
+    }
+}
+
+/// Internal structure providing a convenient way to create error codes
+struct ErrCode {
+    status_code: StatusCode,
+    error_type: ErrorType,
+    error_name: &'static str,
+}
+
+impl ErrCode {
+    fn authentication(error_name: &'static str, status_code: StatusCode) -> ErrCode {
+        ErrCode { status_code, error_name, error_type: ErrorType::AuthenticationError }
+    }
+
+    fn internal(error_name: &'static str, status_code: StatusCode) -> ErrCode {
+        ErrCode { status_code, error_name, error_type: ErrorType::InternalError }
+    }
+
+    fn invalid(error_name: &'static str, status_code: StatusCode) -> ErrCode {
+        ErrCode { status_code, error_name, error_type: ErrorType::InvalidRequestError }
+    }
+}
+
+#[allow(clippy::enum_variant_names)]
+enum ErrorType {
+    InternalError,
+    InvalidRequestError,
+    AuthenticationError,
+}
+
+impl fmt::Display for ErrorType {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        use ErrorType::*;
+
+        match self {
+            InternalError => write!(f, "internal"),
+            InvalidRequestError => write!(f, "invalid_request"),
+            AuthenticationError => write!(f, "auth"),
+        }
+    }
+}

dump/src/reader/v5/keys.rs

@@ -0,0 +1,83 @@
+use serde::Deserialize;
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+use super::meta::{IndexUid, StarOr};
+
+pub type KeyId = Uuid;
+
+#[derive(Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Key {
+    pub description: Option<String>,
+    pub name: Option<String>,
+    pub uid: KeyId,
+    pub actions: Vec<Action>,
+    pub indexes: Vec<StarOr<IndexUid>>,
+    #[serde(with = "time::serde::rfc3339::option")]
+    pub expires_at: Option<OffsetDateTime>,
+    #[serde(with = "time::serde::rfc3339")]
+    pub created_at: OffsetDateTime,
+    #[serde(with = "time::serde::rfc3339")]
+    pub updated_at: OffsetDateTime,
+}
+
+#[derive(Copy, Clone, Deserialize, Debug, Eq, PartialEq, Hash)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[repr(u8)]
+pub enum Action {
+    #[serde(rename = "*")]
+    All = 0,
+    #[serde(rename = "search")]
+    Search,
+    #[serde(rename = "documents.*")]
+    DocumentsAll,
+    #[serde(rename = "documents.add")]
+    DocumentsAdd,
+    #[serde(rename = "documents.get")]
+    DocumentsGet,
+    #[serde(rename = "documents.delete")]
+    DocumentsDelete,
+    #[serde(rename = "indexes.*")]
+    IndexesAll,
+    #[serde(rename = "indexes.create")]
+    IndexesAdd,
+    #[serde(rename = "indexes.get")]
+    IndexesGet,
+    #[serde(rename = "indexes.update")]
+    IndexesUpdate,
+    #[serde(rename = "indexes.delete")]
+    IndexesDelete,
+    #[serde(rename = "tasks.*")]
+    TasksAll,
+    #[serde(rename = "tasks.get")]
+    TasksGet,
+    #[serde(rename = "settings.*")]
+    SettingsAll,
+    #[serde(rename = "settings.get")]
+    SettingsGet,
+    #[serde(rename = "settings.update")]
+    SettingsUpdate,
+    #[serde(rename = "stats.*")]
+    StatsAll,
+    #[serde(rename = "stats.get")]
+    StatsGet,
+    #[serde(rename = "metrics.*")]
+    MetricsAll,
+    #[serde(rename = "metrics.get")]
+    MetricsGet,
+    #[serde(rename = "dumps.*")]
+    DumpsAll,
+    #[serde(rename = "dumps.create")]
+    DumpsCreate,
+    #[serde(rename = "version")]
+    Version,
+    #[serde(rename = "keys.create")]
+    KeysAdd,
+    #[serde(rename = "keys.get")]
+    KeysGet,
+    #[serde(rename = "keys.update")]
+    KeysUpdate,
+    #[serde(rename = "keys.delete")]
+    KeysDelete,
+}

dump/src/reader/v5/meta.rs

@@ -0,0 +1,139 @@
+use std::fmt::{self, Display, Formatter};
+use std::marker::PhantomData;
+use std::str::FromStr;
+
+use serde::de::Visitor;
+use serde::{Deserialize, Deserializer};
+use uuid::Uuid;
+
+use super::settings::{Settings, Unchecked};
+
+#[derive(Deserialize, Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct IndexUuid {
+    pub uid: String,
+    pub index_meta: IndexMeta,
+}
+
+#[derive(Deserialize, Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct IndexMeta {
+    pub uuid: Uuid,
+    pub creation_task_id: usize,
+}
+
+// There is one in each indexes under `meta.json`.
+#[derive(Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct DumpMeta {
+    pub settings: Settings<Unchecked>,
+    pub primary_key: Option<String>,
+}
+
+#[derive(Deserialize, Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct IndexUid(pub String);
+
+impl TryFrom<String> for IndexUid {
+    type Error = IndexUidFormatError;
+
+    fn try_from(uid: String) -> Result<Self, Self::Error> {
+        if !uid.chars().all(|x| x.is_ascii_alphanumeric() || x == '-' || x == '_')
+            || uid.is_empty()
+            || uid.len() > 400
+        {
+            Err(IndexUidFormatError { invalid_uid: uid })
+        } else {
+            Ok(IndexUid(uid))
+        }
+    }
+}
+
+impl FromStr for IndexUid {
+    type Err = IndexUidFormatError;
+
+    fn from_str(uid: &str) -> Result<IndexUid, IndexUidFormatError> {
+        uid.to_string().try_into()
+    }
+}
+
+impl From<IndexUid> for String {
+    fn from(uid: IndexUid) -> Self {
+        uid.into_inner()
+    }
+}
+
+#[derive(Debug)]
+pub struct IndexUidFormatError {
+    pub invalid_uid: String,
+}
+
+impl Display for IndexUidFormatError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        write!(
+            f,
+            "invalid index uid `{}`, the uid must be an integer \
+            or a string containing only alphanumeric characters \
+            a-z A-Z 0-9, hyphens - and underscores _.",
+            self.invalid_uid,
+        )
+    }
+}
+
+impl std::error::Error for IndexUidFormatError {}
+
+/// A type that tries to match either a star (*) or
+/// any other thing that implements `FromStr`.
+#[derive(Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum StarOr<T> {
+    Star,
+    Other(T),
+}
+
+impl<'de, T, E> Deserialize<'de> for StarOr<T>
+where
+    T: FromStr<Err = E>,
+    E: Display,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        /// Serde can't differentiate between `StarOr::Star` and `StarOr::Other` without a tag.
+        /// Simply using `#[serde(untagged)]` + `#[serde(rename="*")]` will lead to attempting to
+        /// deserialize everything as a `StarOr::Other`, including "*".
+        /// [`#[serde(other)]`](https://serde.rs/variant-attrs.html#other) might have helped but is
+        /// not supported on untagged enums.
+        struct StarOrVisitor<T>(PhantomData<T>);
+
+        impl<'de, T, FE> Visitor<'de> for StarOrVisitor<T>
+        where
+            T: FromStr<Err = FE>,
+            FE: Display,
+        {
+            type Value = StarOr<T>;
+
+            fn expecting(&self, formatter: &mut Formatter) -> std::fmt::Result {
+                formatter.write_str("a string")
+            }
+
+            fn visit_str<SE>(self, v: &str) -> Result<Self::Value, SE>
+            where
+                SE: serde::de::Error,
+            {
+                match v {
+                    "*" => Ok(StarOr::Star),
+                    v => {
+                        let other = FromStr::from_str(v).map_err(|e: T::Err| {
+                            SE::custom(format!("Invalid `other` value: {}", e))
+                        })?;
+                        Ok(StarOr::Other(other))
+                    }
+                }
+            }
+        }
+
+        deserializer.deserialize_str(StarOrVisitor(PhantomData))
+    }
+}

dump/src/reader/v5/mod.rs

@@ -0,0 +1,350 @@
+//! Here is what a dump v5 look like.
+//!
+//! ```text
+//! .
+//! ├── indexes
+//! │   ├── 22c269d8-fbbd-4416-bd46-7c7c02849325
+//! │   │   ├── documents.jsonl
+//! │   │   └── meta.json
+//! │   ├── 6d0471ba-2ed1-41de-8ea6-10db10fa2bb8
+//! │   │   ├── documents.jsonl
+//! │   │   └── meta.json
+//! │   └── f7d53ec4-0748-48e6-b66f-1fca9944b0fa
+//! │       ├── documents.jsonl
+//! │       └── meta.json
+//! ├── index_uuids
+//! │   └── data.jsonl
+//! ├── instance-uid
+//! ├── keys
+//! ├── metadata.json
+//! └── updates
+//!     ├── data.jsonl
+//!     └── updates_files
+//!         └── c83a004a-da98-4b94-b245-3256266c7281
+//! ```
+//!
+//! Here is what `index_uuids/data.jsonl` looks like;
+//!
+//! ```json
+//! {"uid":"dnd_spells","index_meta":{"uuid":"22c269d8-fbbd-4416-bd46-7c7c02849325","creation_task_id":9}}
+//! {"uid":"movies","index_meta":{"uuid":"6d0471ba-2ed1-41de-8ea6-10db10fa2bb8","creation_task_id":1}}
+//! {"uid":"products","index_meta":{"uuid":"f7d53ec4-0748-48e6-b66f-1fca9944b0fa","creation_task_id":4}}
+//! ```
+//!
+
+use std::fs::{self, File};
+use std::io::{BufRead, BufReader, ErrorKind, Seek, SeekFrom};
+use std::path::Path;
+
+use serde::{Deserialize, Serialize};
+use tempfile::TempDir;
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+use super::compat::v5_to_v6::CompatV5ToV6;
+use super::Document;
+use crate::{Error, IndexMetadata, Result, Version};
+
+pub mod errors;
+pub mod keys;
+pub mod meta;
+pub mod settings;
+pub mod tasks;
+
+pub type Settings<T> = settings::Settings<T>;
+pub type Checked = settings::Checked;
+pub type Unchecked = settings::Unchecked;
+
+pub type Task = tasks::Task;
+pub type Key = keys::Key;
+
+// ===== Other types to clarify the code of the compat module
+// everything related to the tasks
+pub type Status = tasks::TaskStatus;
+pub type Details = tasks::TaskDetails;
+
+// everything related to the settings
+pub type Setting<T> = settings::Setting<T>;
+pub type TypoTolerance = settings::TypoSettings;
+pub type MinWordSizeForTypos = settings::MinWordSizeTyposSetting;
+
+// everything related to the api keys
+pub type Action = keys::Action;
+pub type StarOr<T> = meta::StarOr<T>;
+
+// everything related to the errors
+pub type ResponseError = errors::ResponseError;
+pub type Code = errors::Code;
+
+#[derive(Serialize, Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct Metadata {
+    db_version: String,
+    index_db_size: usize,
+    update_db_size: usize,
+    #[serde(with = "time::serde::rfc3339")]
+    dump_date: OffsetDateTime,
+}
+
+pub struct V5Reader {
+    dump: TempDir,
+    metadata: Metadata,
+    tasks: BufReader<File>,
+    keys: BufReader<File>,
+    index_uuid: Vec<meta::IndexUuid>,
+}
+
+impl V5Reader {
+    pub fn open(dump: TempDir) -> Result<Self> {
+        let meta_file = fs::read(dump.path().join("metadata.json"))?;
+        let metadata = serde_json::from_reader(&*meta_file)?;
+        let index_uuid = File::open(dump.path().join("index_uuids/data.jsonl"))?;
+        let index_uuid = BufReader::new(index_uuid);
+        let index_uuid = index_uuid
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) })
+            .collect::<Result<Vec<_>>>()?;
+
+        Ok(V5Reader {
+            metadata,
+            tasks: BufReader::new(
+                File::open(dump.path().join("updates").join("data.jsonl")).unwrap(),
+            ),
+            keys: BufReader::new(File::open(dump.path().join("keys"))?),
+            index_uuid,
+            dump,
+        })
+    }
+
+    pub fn to_v6(self) -> CompatV5ToV6 {
+        CompatV5ToV6::new_v5(self)
+    }
+
+    pub fn version(&self) -> Version {
+        Version::V5
+    }
+
+    pub fn date(&self) -> Option<OffsetDateTime> {
+        Some(self.metadata.dump_date)
+    }
+
+    pub fn instance_uid(&self) -> Result<Option<Uuid>> {
+        match fs::read_to_string(self.dump.path().join("instance-uid")) {
+            Ok(uuid) => Ok(Some(Uuid::parse_str(&uuid)?)),
+            Err(e) if e.kind() == ErrorKind::NotFound => Ok(None),
+            Err(e) => Err(e.into()),
+        }
+    }
+
+    pub fn indexes(&self) -> Result<impl Iterator<Item = Result<V5IndexReader>> + '_> {
+        Ok(self.index_uuid.iter().map(|index| -> Result<_> {
+            V5IndexReader::new(
+                index.uid.clone(),
+                &self.dump.path().join("indexes").join(index.index_meta.uuid.to_string()),
+            )
+        }))
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Box<dyn Iterator<Item = Result<(Task, Option<Box<super::UpdateFile>>)>> + '_> {
+        Box::new((&mut self.tasks).lines().map(|line| -> Result<_> {
+            let task: Task = serde_json::from_str(&line?)?;
+            if !task.is_finished() {
+                if let Some(uuid) = task.get_content_uuid() {
+                    let update_file_path = self
+                        .dump
+                        .path()
+                        .join("updates")
+                        .join("updates_files")
+                        .join(uuid.to_string());
+                    Ok((
+                        task,
+                        Some(
+                            Box::new(UpdateFile::new(&update_file_path)?) as Box<super::UpdateFile>
+                        ),
+                    ))
+                } else {
+                    Ok((task, None))
+                }
+            } else {
+                Ok((task, None))
+            }
+        }))
+    }
+
+    pub fn keys(&mut self) -> Result<Box<dyn Iterator<Item = Result<Key>> + '_>> {
+        self.keys.seek(SeekFrom::Start(0))?;
+        Ok(Box::new(
+            (&mut self.keys).lines().map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) }),
+        ))
+    }
+}
+
+pub struct V5IndexReader {
+    metadata: IndexMetadata,
+    settings: Settings<Checked>,
+
+    documents: BufReader<File>,
+}
+
+impl V5IndexReader {
+    pub fn new(name: String, path: &Path) -> Result<Self> {
+        let meta = File::open(path.join("meta.json"))?;
+        let meta: meta::DumpMeta = serde_json::from_reader(meta)?;
+
+        let metadata = IndexMetadata {
+            uid: name,
+            primary_key: meta.primary_key,
+            // FIXME: Iterate over the whole task queue to find the creation and last update date.
+            created_at: OffsetDateTime::now_utc(),
+            updated_at: OffsetDateTime::now_utc(),
+        };
+
+        let ret = V5IndexReader {
+            metadata,
+            settings: meta.settings.check(),
+            documents: BufReader::new(File::open(path.join("documents.jsonl"))?),
+        };
+
+        Ok(ret)
+    }
+
+    pub fn metadata(&self) -> &IndexMetadata {
+        &self.metadata
+    }
+
+    pub fn documents(&mut self) -> Result<impl Iterator<Item = Result<Document>> + '_> {
+        Ok((&mut self.documents)
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) }))
+    }
+
+    pub fn settings(&mut self) -> Result<Settings<Checked>> {
+        Ok(self.settings.clone())
+    }
+}
+
+pub struct UpdateFile {
+    reader: BufReader<File>,
+}
+
+impl UpdateFile {
+    fn new(path: &Path) -> Result<Self> {
+        Ok(UpdateFile { reader: BufReader::new(File::open(path)?) })
+    }
+}
+
+impl Iterator for UpdateFile {
+    type Item = Result<Document>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        (&mut self.reader)
+            .lines()
+            .map(|line| {
+                line.map_err(Error::from)
+                    .and_then(|line| serde_json::from_str(&line).map_err(Error::from))
+            })
+            .next()
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fs::File;
+    use std::io::BufReader;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use tempfile::TempDir;
+
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn read_dump_v5() {
+        let dump = File::open("tests/assets/v5.dump").unwrap();
+        let dir = TempDir::new().unwrap();
+        let mut dump = BufReader::new(dump);
+        let gz = GzDecoder::new(&mut dump);
+        let mut archive = tar::Archive::new(gz);
+        archive.unpack(dir.path()).unwrap();
+
+        let mut dump = V5Reader::open(dir).unwrap();
+
+        // top level infos
+        insta::assert_display_snapshot!(dump.date().unwrap(), @"2022-10-04 15:55:10.344982459 +00:00:00");
+        insta::assert_display_snapshot!(dump.instance_uid().unwrap().unwrap(), @"9e15e977-f2ae-4761-943f-1eaf75fd736d");
+
+        // tasks
+        let tasks = dump.tasks().collect::<Result<Vec<_>>>().unwrap();
+        let (tasks, mut update_files): (Vec<_>, Vec<_>) = tasks.into_iter().unzip();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(tasks), @"e159863f0442b2e987ce37fbd57af76b");
+        assert_eq!(update_files.len(), 22);
+        assert!(update_files[0].is_none()); // the dump creation
+        assert!(update_files[1].is_some()); // the enqueued document addition
+        assert!(update_files[2..].iter().all(|u| u.is_none())); // everything already processed
+
+        let update_file = update_files.remove(1).unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(update_file), @"7b8889539b669c7b9ddba448bafa385d");
+
+        // keys
+        let keys = dump.keys().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        meili_snap::snapshot_hash!(meili_snap::json_string!(keys), @"091ddad754f3cc7cf1d03a477855e819");
+
+        // indexes
+        let mut indexes = dump.indexes().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        // the index are not ordered in any way by default
+        indexes.sort_by_key(|index| index.metadata().uid.to_string());
+
+        let mut products = indexes.pop().unwrap();
+        let mut movies = indexes.pop().unwrap();
+        let mut spells = indexes.pop().unwrap();
+        assert!(indexes.is_empty());
+
+        // products
+        insta::assert_json_snapshot!(products.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "products",
+          "primaryKey": "sku",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", products.settings()), @"b392b928dab63468318b2bdaad844c5a");
+        let documents = products.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"b01c8371aea4c7171af0d4d846a2bdca");
+
+        // movies
+        insta::assert_json_snapshot!(movies.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "movies",
+          "primaryKey": "id",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", movies.settings()), @"2f881248b7c3623e2ba2885dbf0b2c18");
+        let documents = movies.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 200);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"e962baafd2fbae4cdd14e876053b0c5a");
+
+        // spells
+        insta::assert_json_snapshot!(spells.metadata(), { ".createdAt" => "[now]", ".updatedAt" => "[now]" }, @r###"
+        {
+          "uid": "dnd_spells",
+          "primaryKey": "index",
+          "createdAt": "[now]",
+          "updatedAt": "[now]"
+        }
+        "###);
+
+        meili_snap::snapshot_hash!(format!("{:#?}", spells.settings()), @"ade154e63ab713de67919892917d3d9d");
+        let documents = spells.documents().unwrap().collect::<Result<Vec<_>>>().unwrap();
+        assert_eq!(documents.len(), 10);
+        meili_snap::snapshot_hash!(format!("{:#?}", documents), @"235016433dd04262c7f2da01d1e808ce");
+    }
+}

dump/src/reader/v5/settings.rs

@@ -0,0 +1,239 @@
+use std::collections::{BTreeMap, BTreeSet};
+use std::marker::PhantomData;
+
+use serde::{Deserialize, Deserializer, Serialize};
+
+#[derive(Clone, Default, Debug, Serialize, PartialEq, Eq)]
+pub struct Checked;
+
+#[derive(Clone, Default, Debug, Serialize, Deserialize, PartialEq, Eq)]
+pub struct Unchecked;
+
+/// Holds all the settings for an index. `T` can either be `Checked` if they represents settings
+/// whose validity is guaranteed, or `Unchecked` if they need to be validated. In the later case, a
+/// call to `check` will return a `Settings<Checked>` from a `Settings<Unchecked>`.
+#[derive(Debug, Clone, Default, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+#[serde(bound(serialize = "T: Serialize", deserialize = "T: Deserialize<'static>"))]
+pub struct Settings<T> {
+    #[serde(default)]
+    pub displayed_attributes: Setting<Vec<String>>,
+
+    #[serde(default)]
+    pub searchable_attributes: Setting<Vec<String>>,
+
+    #[serde(default)]
+    pub filterable_attributes: Setting<BTreeSet<String>>,
+    #[serde(default)]
+    pub sortable_attributes: Setting<BTreeSet<String>>,
+    #[serde(default)]
+    pub ranking_rules: Setting<Vec<String>>,
+    #[serde(default)]
+    pub stop_words: Setting<BTreeSet<String>>,
+    #[serde(default)]
+    pub synonyms: Setting<BTreeMap<String, Vec<String>>>,
+    #[serde(default)]
+    pub distinct_attribute: Setting<String>,
+    #[serde(default)]
+    pub typo_tolerance: Setting<TypoSettings>,
+    #[serde(default)]
+    pub faceting: Setting<FacetingSettings>,
+    #[serde(default)]
+    pub pagination: Setting<PaginationSettings>,
+
+    #[serde(skip)]
+    pub _kind: PhantomData<T>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Copy)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum Setting<T> {
+    Set(T),
+    Reset,
+    NotSet,
+}
+
+impl<T> Default for Setting<T> {
+    fn default() -> Self {
+        Self::NotSet
+    }
+}
+
+impl<T> Setting<T> {
+    pub fn set(self) -> Option<T> {
+        match self {
+            Self::Set(value) => Some(value),
+            _ => None,
+        }
+    }
+
+    pub const fn as_ref(&self) -> Setting<&T> {
+        match *self {
+            Self::Set(ref value) => Setting::Set(value),
+            Self::Reset => Setting::Reset,
+            Self::NotSet => Setting::NotSet,
+        }
+    }
+
+    pub const fn is_not_set(&self) -> bool {
+        matches!(self, Self::NotSet)
+    }
+
+    /// If `Self` is `Reset`, then map self to `Set` with the provided `val`.
+    pub fn or_reset(self, val: T) -> Self {
+        match self {
+            Self::Reset => Self::Set(val),
+            otherwise => otherwise,
+        }
+    }
+}
+
+impl<'de, T: Deserialize<'de>> Deserialize<'de> for Setting<T> {
+    fn deserialize<D>(deserializer: D) -> std::result::Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        Deserialize::deserialize(deserializer).map(|x| match x {
+            Some(x) => Self::Set(x),
+            None => Self::Reset, // Reset is forced by sending null value
+        })
+    }
+}
+
+#[derive(Debug, Clone, Default, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+pub struct MinWordSizeTyposSetting {
+    #[serde(default)]
+    pub one_typo: Setting<u8>,
+    #[serde(default)]
+    pub two_typos: Setting<u8>,
+}
+
+#[derive(Debug, Clone, Default, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+pub struct TypoSettings {
+    #[serde(default)]
+    pub enabled: Setting<bool>,
+    #[serde(default)]
+    pub min_word_size_for_typos: Setting<MinWordSizeTyposSetting>,
+    #[serde(default)]
+    pub disable_on_words: Setting<BTreeSet<String>>,
+    #[serde(default)]
+    pub disable_on_attributes: Setting<BTreeSet<String>>,
+}
+
+#[derive(Debug, Clone, Default, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+pub struct FacetingSettings {
+    #[serde(default)]
+    pub max_values_per_facet: Setting<usize>,
+}
+
+#[derive(Debug, Clone, Default, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+pub struct PaginationSettings {
+    #[serde(default)]
+    pub max_total_hits: Setting<usize>,
+}
+
+impl Settings<Checked> {
+    pub fn cleared() -> Settings<Checked> {
+        Settings {
+            displayed_attributes: Setting::Reset,
+            searchable_attributes: Setting::Reset,
+            filterable_attributes: Setting::Reset,
+            sortable_attributes: Setting::Reset,
+            ranking_rules: Setting::Reset,
+            stop_words: Setting::Reset,
+            synonyms: Setting::Reset,
+            distinct_attribute: Setting::Reset,
+            typo_tolerance: Setting::Reset,
+            faceting: Setting::Reset,
+            pagination: Setting::Reset,
+            _kind: PhantomData,
+        }
+    }
+
+    pub fn into_unchecked(self) -> Settings<Unchecked> {
+        let Self {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes,
+            sortable_attributes,
+            ranking_rules,
+            stop_words,
+            synonyms,
+            distinct_attribute,
+            typo_tolerance,
+            faceting,
+            pagination,
+            ..
+        } = self;
+
+        Settings {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes,
+            sortable_attributes,
+            ranking_rules,
+            stop_words,
+            synonyms,
+            distinct_attribute,
+            typo_tolerance,
+            faceting,
+            pagination,
+            _kind: PhantomData,
+        }
+    }
+}
+
+impl Settings<Unchecked> {
+    pub fn check(self) -> Settings<Checked> {
+        let displayed_attributes = match self.displayed_attributes {
+            Setting::Set(fields) => {
+                if fields.iter().any(|f| f == "*") {
+                    Setting::Reset
+                } else {
+                    Setting::Set(fields)
+                }
+            }
+            otherwise => otherwise,
+        };
+
+        let searchable_attributes = match self.searchable_attributes {
+            Setting::Set(fields) => {
+                if fields.iter().any(|f| f == "*") {
+                    Setting::Reset
+                } else {
+                    Setting::Set(fields)
+                }
+            }
+            otherwise => otherwise,
+        };
+
+        Settings {
+            displayed_attributes,
+            searchable_attributes,
+            filterable_attributes: self.filterable_attributes,
+            sortable_attributes: self.sortable_attributes,
+            ranking_rules: self.ranking_rules,
+            stop_words: self.stop_words,
+            synonyms: self.synonyms,
+            distinct_attribute: self.distinct_attribute,
+            typo_tolerance: self.typo_tolerance,
+            faceting: self.faceting,
+            pagination: self.pagination,
+            _kind: PhantomData,
+        }
+    }
+}

dump/src/reader/v5/tasks.rs

@@ -0,0 +1,413 @@
+use serde::Deserialize;
+use time::{Duration, OffsetDateTime};
+use uuid::Uuid;
+
+use super::errors::ResponseError;
+use super::meta::IndexUid;
+use super::settings::{Settings, Unchecked};
+
+pub type TaskId = u32;
+pub type BatchId = u32;
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub struct Task {
+    pub id: TaskId,
+    /// The name of the index the task is targeting. If it isn't targeting any index (i.e Dump task)
+    /// then this is None
+    // TODO: when next forward breaking dumps, it would be a good idea to move this field inside of
+    // the TaskContent.
+    pub content: TaskContent,
+    pub events: Vec<TaskEvent>,
+}
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[allow(clippy::large_enum_variant)]
+pub enum TaskContent {
+    DocumentAddition {
+        index_uid: IndexUid,
+        content_uuid: Uuid,
+        merge_strategy: IndexDocumentsMethod,
+        primary_key: Option<String>,
+        documents_count: usize,
+        allow_index_creation: bool,
+    },
+    DocumentDeletion {
+        index_uid: IndexUid,
+        deletion: DocumentDeletion,
+    },
+    SettingsUpdate {
+        index_uid: IndexUid,
+        settings: Settings<Unchecked>,
+        /// Indicates whether the task was a deletion
+        is_deletion: bool,
+        allow_index_creation: bool,
+    },
+    IndexDeletion {
+        index_uid: IndexUid,
+    },
+    IndexCreation {
+        index_uid: IndexUid,
+        primary_key: Option<String>,
+    },
+    IndexUpdate {
+        index_uid: IndexUid,
+        primary_key: Option<String>,
+    },
+    Dump {
+        uid: String,
+    },
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum IndexDocumentsMethod {
+    /// Replace the previous document with the new one,
+    /// removing all the already known attributes.
+    ReplaceDocuments,
+
+    /// Merge the previous version of the document with the new version,
+    /// replacing old attributes values with the new ones and add the new attributes.
+    UpdateDocuments,
+}
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum DocumentDeletion {
+    Clear,
+    Ids(Vec<String>),
+}
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum TaskEvent {
+    Created(#[serde(with = "time::serde::rfc3339")] OffsetDateTime),
+    Batched {
+        #[serde(with = "time::serde::rfc3339")]
+        timestamp: OffsetDateTime,
+        batch_id: BatchId,
+    },
+    Processing(#[serde(with = "time::serde::rfc3339")] OffsetDateTime),
+    Succeeded {
+        result: TaskResult,
+        #[serde(with = "time::serde::rfc3339")]
+        timestamp: OffsetDateTime,
+    },
+    Failed {
+        error: ResponseError,
+        #[serde(with = "time::serde::rfc3339")]
+        timestamp: OffsetDateTime,
+    },
+}
+
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq)]
+#[cfg_attr(test, derive(serde::Serialize))]
+pub enum TaskResult {
+    DocumentAddition { indexed_documents: u64 },
+    DocumentDeletion { deleted_documents: u64 },
+    ClearAll { deleted_documents: u64 },
+    Other,
+}
+
+impl Task {
+    /// Return true when a task is finished.
+    /// A task is finished when its last state is either `Succeeded` or `Failed`.
+    pub fn is_finished(&self) -> bool {
+        self.events.last().map_or(false, |event| {
+            matches!(event, TaskEvent::Succeeded { .. } | TaskEvent::Failed { .. })
+        })
+    }
+
+    /// Return the content_uuid of the `Task` if there is one.
+    pub fn get_content_uuid(&self) -> Option<Uuid> {
+        match self {
+            Task { content: TaskContent::DocumentAddition { content_uuid, .. }, .. } => {
+                Some(*content_uuid)
+            }
+            _ => None,
+        }
+    }
+
+    pub fn index_uid(&self) -> Option<&str> {
+        match &self.content {
+            TaskContent::DocumentAddition { index_uid, .. }
+            | TaskContent::DocumentDeletion { index_uid, .. }
+            | TaskContent::SettingsUpdate { index_uid, .. }
+            | TaskContent::IndexDeletion { index_uid }
+            | TaskContent::IndexCreation { index_uid, .. }
+            | TaskContent::IndexUpdate { index_uid, .. } => Some(index_uid.as_str()),
+            TaskContent::Dump { .. } => None,
+        }
+    }
+}
+
+impl IndexUid {
+    pub fn into_inner(self) -> String {
+        self.0
+    }
+
+    /// Return a reference over the inner str.
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+}
+
+impl std::ops::Deref for IndexUid {
+    type Target = str;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+#[derive(Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[cfg_attr(test, serde(rename_all = "camelCase"))]
+pub struct TaskView {
+    pub uid: TaskId,
+    pub index_uid: Option<String>,
+    pub status: TaskStatus,
+    #[cfg_attr(test, serde(rename = "type"))]
+    pub task_type: TaskType,
+    #[cfg_attr(test, serde(skip_serializing_if = "Option::is_none"))]
+    pub details: Option<TaskDetails>,
+    #[cfg_attr(test, serde(skip_serializing_if = "Option::is_none"))]
+    pub error: Option<ResponseError>,
+    #[cfg_attr(test, serde(serialize_with = "serialize_duration"))]
+    pub duration: Option<Duration>,
+    #[cfg_attr(test, serde(serialize_with = "time::serde::rfc3339::serialize"))]
+    pub enqueued_at: OffsetDateTime,
+    #[cfg_attr(test, serde(serialize_with = "time::serde::rfc3339::option::serialize"))]
+    pub started_at: Option<OffsetDateTime>,
+    #[cfg_attr(test, serde(serialize_with = "time::serde::rfc3339::option::serialize"))]
+    pub finished_at: Option<OffsetDateTime>,
+}
+
+impl From<Task> for TaskView {
+    fn from(task: Task) -> Self {
+        let index_uid = task.index_uid().map(String::from);
+        let Task { id, content, events } = task;
+
+        let (task_type, mut details) = match content {
+            TaskContent::DocumentAddition { documents_count, .. } => {
+                let details = TaskDetails::DocumentAddition {
+                    received_documents: documents_count,
+                    indexed_documents: None,
+                };
+
+                (TaskType::DocumentAdditionOrUpdate, Some(details))
+            }
+            TaskContent::DocumentDeletion { deletion: DocumentDeletion::Ids(ids), .. } => (
+                TaskType::DocumentDeletion,
+                Some(TaskDetails::DocumentDeletion {
+                    received_document_ids: ids.len(),
+                    deleted_documents: None,
+                }),
+            ),
+            TaskContent::DocumentDeletion { deletion: DocumentDeletion::Clear, .. } => (
+                TaskType::DocumentDeletion,
+                Some(TaskDetails::ClearAll { deleted_documents: None }),
+            ),
+            TaskContent::IndexDeletion { .. } => {
+                (TaskType::IndexDeletion, Some(TaskDetails::ClearAll { deleted_documents: None }))
+            }
+            TaskContent::SettingsUpdate { settings, .. } => {
+                (TaskType::SettingsUpdate, Some(TaskDetails::Settings { settings }))
+            }
+            TaskContent::IndexCreation { primary_key, .. } => {
+                (TaskType::IndexCreation, Some(TaskDetails::IndexInfo { primary_key }))
+            }
+            TaskContent::IndexUpdate { primary_key, .. } => {
+                (TaskType::IndexUpdate, Some(TaskDetails::IndexInfo { primary_key }))
+            }
+            TaskContent::Dump { uid } => {
+                (TaskType::DumpCreation, Some(TaskDetails::Dump { dump_uid: uid }))
+            }
+        };
+
+        // An event always has at least one event: "Created"
+        let (status, error, finished_at) = match events.last().unwrap() {
+            TaskEvent::Created(_) => (TaskStatus::Enqueued, None, None),
+            TaskEvent::Batched { .. } => (TaskStatus::Enqueued, None, None),
+            TaskEvent::Processing(_) => (TaskStatus::Processing, None, None),
+            TaskEvent::Succeeded { timestamp, result } => {
+                match (result, &mut details) {
+                    (
+                        TaskResult::DocumentAddition { indexed_documents: num, .. },
+                        Some(TaskDetails::DocumentAddition { ref mut indexed_documents, .. }),
+                    ) => {
+                        indexed_documents.replace(*num);
+                    }
+                    (
+                        TaskResult::DocumentDeletion { deleted_documents: docs, .. },
+                        Some(TaskDetails::DocumentDeletion { ref mut deleted_documents, .. }),
+                    ) => {
+                        deleted_documents.replace(*docs);
+                    }
+                    (
+                        TaskResult::ClearAll { deleted_documents: docs },
+                        Some(TaskDetails::ClearAll { ref mut deleted_documents }),
+                    ) => {
+                        deleted_documents.replace(*docs);
+                    }
+                    _ => (),
+                }
+                (TaskStatus::Succeeded, None, Some(*timestamp))
+            }
+            TaskEvent::Failed { timestamp, error } => {
+                match details {
+                    Some(TaskDetails::DocumentDeletion { ref mut deleted_documents, .. }) => {
+                        deleted_documents.replace(0);
+                    }
+                    Some(TaskDetails::ClearAll { ref mut deleted_documents, .. }) => {
+                        deleted_documents.replace(0);
+                    }
+                    Some(TaskDetails::DocumentAddition { ref mut indexed_documents, .. }) => {
+                        indexed_documents.replace(0);
+                    }
+                    _ => (),
+                }
+                (TaskStatus::Failed, Some(error.clone()), Some(*timestamp))
+            }
+        };
+
+        let enqueued_at = match events.first() {
+            Some(TaskEvent::Created(ts)) => *ts,
+            _ => unreachable!("A task must always have a creation event."),
+        };
+
+        let started_at = events.iter().find_map(|e| match e {
+            TaskEvent::Processing(ts) => Some(*ts),
+            _ => None,
+        });
+
+        let duration = finished_at.zip(started_at).map(|(tf, ts)| (tf - ts));
+
+        Self {
+            uid: id,
+            index_uid,
+            status,
+            task_type,
+            details,
+            error,
+            duration,
+            enqueued_at,
+            started_at,
+            finished_at,
+        }
+    }
+}
+
+#[derive(Debug, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub enum TaskType {
+    IndexCreation,
+    IndexUpdate,
+    IndexDeletion,
+    DocumentAdditionOrUpdate,
+    DocumentDeletion,
+    SettingsUpdate,
+    DumpCreation,
+}
+
+impl From<TaskContent> for TaskType {
+    fn from(other: TaskContent) -> Self {
+        match other {
+            TaskContent::IndexCreation { .. } => TaskType::IndexCreation,
+            TaskContent::IndexUpdate { .. } => TaskType::IndexUpdate,
+            TaskContent::IndexDeletion { .. } => TaskType::IndexDeletion,
+            TaskContent::DocumentAddition { .. } => TaskType::DocumentAdditionOrUpdate,
+            TaskContent::DocumentDeletion { .. } => TaskType::DocumentDeletion,
+            TaskContent::SettingsUpdate { .. } => TaskType::SettingsUpdate,
+            TaskContent::Dump { .. } => TaskType::DumpCreation,
+        }
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Deserialize)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[serde(rename_all = "camelCase")]
+pub enum TaskStatus {
+    Enqueued,
+    Processing,
+    Succeeded,
+    Failed,
+}
+
+#[derive(Debug)]
+#[cfg_attr(test, derive(serde::Serialize))]
+#[cfg_attr(test, serde(untagged))]
+#[allow(clippy::large_enum_variant)]
+pub enum TaskDetails {
+    #[cfg_attr(test, serde(rename_all = "camelCase"))]
+    DocumentAddition { received_documents: usize, indexed_documents: Option<u64> },
+    #[cfg_attr(test, serde(rename_all = "camelCase"))]
+    Settings {
+        #[cfg_attr(test, serde(flatten))]
+        settings: Settings<Unchecked>,
+    },
+    #[cfg_attr(test, serde(rename_all = "camelCase"))]
+    IndexInfo { primary_key: Option<String> },
+    #[cfg_attr(test, serde(rename_all = "camelCase"))]
+    DocumentDeletion { received_document_ids: usize, deleted_documents: Option<u64> },
+    #[cfg_attr(test, serde(rename_all = "camelCase"))]
+    ClearAll { deleted_documents: Option<u64> },
+    #[cfg_attr(test, serde(rename_all = "camelCase"))]
+    Dump { dump_uid: String },
+}
+
+/// Serialize a `time::Duration` as a best effort ISO 8601 while waiting for
+/// https://github.com/time-rs/time/issues/378.
+/// This code is a port of the old code of time that was removed in 0.2.
+#[cfg(test)]
+fn serialize_duration<S: serde::Serializer>(
+    duration: &Option<Duration>,
+    serializer: S,
+) -> Result<S::Ok, S::Error> {
+    use std::fmt::Write;
+
+    match duration {
+        Some(duration) => {
+            // technically speaking, negative duration is not valid ISO 8601
+            if duration.is_negative() {
+                return serializer.serialize_none();
+            }
+
+            const SECS_PER_DAY: i64 = Duration::DAY.whole_seconds();
+            let secs = duration.whole_seconds();
+            let days = secs / SECS_PER_DAY;
+            let secs = secs - days * SECS_PER_DAY;
+            let hasdate = days != 0;
+            let nanos = duration.subsec_nanoseconds();
+            let hastime = (secs != 0 || nanos != 0) || !hasdate;
+
+            // all the following unwrap can't fail
+            let mut res = String::new();
+            write!(&mut res, "P").unwrap();
+
+            if hasdate {
+                write!(&mut res, "{}D", days).unwrap();
+            }
+
+            const NANOS_PER_MILLI: i32 = Duration::MILLISECOND.subsec_nanoseconds();
+            const NANOS_PER_MICRO: i32 = Duration::MICROSECOND.subsec_nanoseconds();
+
+            if hastime {
+                if nanos == 0 {
+                    write!(&mut res, "T{}S", secs).unwrap();
+                } else if nanos % NANOS_PER_MILLI == 0 {
+                    write!(&mut res, "T{}.{:03}S", secs, nanos / NANOS_PER_MILLI).unwrap();
+                } else if nanos % NANOS_PER_MICRO == 0 {
+                    write!(&mut res, "T{}.{:06}S", secs, nanos / NANOS_PER_MICRO).unwrap();
+                } else {
+                    write!(&mut res, "T{}.{:09}S", secs, nanos).unwrap();
+                }
+            }
+
+            serializer.serialize_str(&res)
+        }
+        None => serializer.serialize_none(),
+    }
+}

dump/src/reader/v6/mod.rs

@@ -0,0 +1,189 @@
+use std::fs::{self, File};
+use std::io::{BufRead, BufReader};
+use std::path::Path;
+use std::str::FromStr;
+
+pub use meilisearch_types::milli;
+use tempfile::TempDir;
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+use super::Document;
+use crate::{Error, IndexMetadata, Result, Version};
+
+pub type Metadata = crate::Metadata;
+
+pub type Settings<T> = meilisearch_types::settings::Settings<T>;
+pub type Checked = meilisearch_types::settings::Checked;
+pub type Unchecked = meilisearch_types::settings::Unchecked;
+
+pub type Task = crate::TaskDump;
+pub type Key = meilisearch_types::keys::Key;
+
+// ===== Other types to clarify the code of the compat module
+// everything related to the tasks
+pub type Status = meilisearch_types::tasks::Status;
+pub type Kind = crate::KindDump;
+pub type Details = meilisearch_types::tasks::Details;
+
+// everything related to the settings
+pub type Setting<T> = meilisearch_types::milli::update::Setting<T>;
+pub type TypoTolerance = meilisearch_types::settings::TypoSettings;
+pub type MinWordSizeForTypos = meilisearch_types::settings::MinWordSizeTyposSetting;
+pub type FacetingSettings = meilisearch_types::settings::FacetingSettings;
+pub type PaginationSettings = meilisearch_types::settings::PaginationSettings;
+
+// everything related to the api keys
+pub type Action = meilisearch_types::keys::Action;
+pub type StarOr<T> = meilisearch_types::star_or::StarOr<T>;
+pub type IndexUid = meilisearch_types::index_uid::IndexUid;
+
+// everything related to the errors
+pub type ResponseError = meilisearch_types::error::ResponseError;
+pub type Code = meilisearch_types::error::Code;
+
+pub struct V6Reader {
+    dump: TempDir,
+    instance_uid: Uuid,
+    metadata: Metadata,
+    tasks: BufReader<File>,
+    keys: BufReader<File>,
+}
+
+impl V6Reader {
+    pub fn open(dump: TempDir) -> Result<Self> {
+        let meta_file = fs::read(dump.path().join("metadata.json"))?;
+        let instance_uid = fs::read_to_string(dump.path().join("instance_uid.uuid"))?;
+        let instance_uid = Uuid::from_str(&instance_uid)?;
+
+        Ok(V6Reader {
+            metadata: serde_json::from_reader(&*meta_file)?,
+            instance_uid,
+            tasks: BufReader::new(File::open(dump.path().join("tasks").join("queue.jsonl"))?),
+            keys: BufReader::new(File::open(dump.path().join("keys.jsonl"))?),
+            dump,
+        })
+    }
+
+    pub fn version(&self) -> Version {
+        Version::V6
+    }
+
+    pub fn date(&self) -> Option<OffsetDateTime> {
+        Some(self.metadata.dump_date)
+    }
+
+    pub fn instance_uid(&self) -> Result<Option<Uuid>> {
+        Ok(Some(self.instance_uid))
+    }
+
+    pub fn indexes(&self) -> Result<Box<dyn Iterator<Item = Result<V6IndexReader>> + '_>> {
+        let entries = fs::read_dir(self.dump.path().join("indexes"))?;
+        Ok(Box::new(
+            entries
+                .map(|entry| -> Result<Option<_>> {
+                    let entry = entry?;
+                    if entry.file_type()?.is_dir() {
+                        let index = V6IndexReader::new(
+                            entry.file_name().to_str().ok_or(Error::BadIndexName)?.to_string(),
+                            &entry.path(),
+                        )?;
+                        Ok(Some(index))
+                    } else {
+                        Ok(None)
+                    }
+                })
+                .filter_map(|entry| entry.transpose()),
+        ))
+    }
+
+    pub fn tasks(
+        &mut self,
+    ) -> Box<dyn Iterator<Item = Result<(Task, Option<Box<super::UpdateFile>>)>> + '_> {
+        Box::new((&mut self.tasks).lines().map(|line| -> Result<_> {
+            let task: Task = serde_json::from_str(&line?).unwrap();
+
+            let update_file_path = self
+                .dump
+                .path()
+                .join("tasks")
+                .join("update_files")
+                .join(format!("{}.jsonl", task.uid));
+
+            if update_file_path.exists() {
+                Ok((
+                    task,
+                    Some(Box::new(UpdateFile::new(&update_file_path).unwrap())
+                        as Box<super::UpdateFile>),
+                ))
+            } else {
+                Ok((task, None))
+            }
+        }))
+    }
+
+    pub fn keys(&mut self) -> Box<dyn Iterator<Item = Result<Key>> + '_> {
+        Box::new(
+            (&mut self.keys).lines().map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) }),
+        )
+    }
+}
+
+pub struct UpdateFile {
+    reader: BufReader<File>,
+}
+
+impl UpdateFile {
+    fn new(path: &Path) -> Result<Self> {
+        Ok(UpdateFile { reader: BufReader::new(File::open(path)?) })
+    }
+}
+
+impl Iterator for UpdateFile {
+    type Item = Result<Document>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        (&mut self.reader)
+            .lines()
+            .map(|line| {
+                line.map_err(Error::from)
+                    .and_then(|line| serde_json::from_str(&line).map_err(Error::from))
+            })
+            .next()
+    }
+}
+
+pub struct V6IndexReader {
+    metadata: IndexMetadata,
+    documents: BufReader<File>,
+    settings: BufReader<File>,
+}
+
+impl V6IndexReader {
+    pub fn new(_name: String, path: &Path) -> Result<Self> {
+        let metadata = File::open(path.join("metadata.json"))?;
+
+        let ret = V6IndexReader {
+            metadata: serde_json::from_reader(metadata)?,
+            documents: BufReader::new(File::open(path.join("documents.jsonl"))?),
+            settings: BufReader::new(File::open(path.join("settings.json"))?),
+        };
+
+        Ok(ret)
+    }
+
+    pub fn metadata(&self) -> &IndexMetadata {
+        &self.metadata
+    }
+
+    pub fn documents(&mut self) -> Result<impl Iterator<Item = Result<Document>> + '_> {
+        Ok((&mut self.documents)
+            .lines()
+            .map(|line| -> Result<_> { Ok(serde_json::from_str(&line?)?) }))
+    }
+
+    pub fn settings(&mut self) -> Result<Settings<Checked>> {
+        let settings: Settings<Unchecked> = serde_json::from_reader(&mut self.settings)?;
+        Ok(settings.check())
+    }
+}

dump/src/writer.rs

@@ -0,0 +1,350 @@
+use std::fs::{self, File};
+use std::io::{BufWriter, Write};
+use std::path::PathBuf;
+
+use flate2::write::GzEncoder;
+use flate2::Compression;
+use meilisearch_types::keys::Key;
+use meilisearch_types::settings::{Checked, Settings};
+use serde_json::{Map, Value};
+use tempfile::TempDir;
+use time::OffsetDateTime;
+use uuid::Uuid;
+
+use crate::reader::Document;
+use crate::{IndexMetadata, Metadata, Result, TaskDump, CURRENT_DUMP_VERSION};
+
+pub struct DumpWriter {
+    dir: TempDir,
+}
+
+impl DumpWriter {
+    pub fn new(instance_uuid: Option<Uuid>) -> Result<DumpWriter> {
+        let dir = TempDir::new()?;
+
+        if let Some(instance_uuid) = instance_uuid {
+            fs::write(
+                dir.path().join("instance_uid.uuid"),
+                &instance_uuid.as_hyphenated().to_string(),
+            )?;
+        }
+
+        let metadata = Metadata {
+            dump_version: CURRENT_DUMP_VERSION,
+            db_version: env!("CARGO_PKG_VERSION").to_string(),
+            dump_date: OffsetDateTime::now_utc(),
+        };
+        fs::write(dir.path().join("metadata.json"), serde_json::to_string(&metadata)?)?;
+
+        std::fs::create_dir(&dir.path().join("indexes"))?;
+
+        Ok(DumpWriter { dir })
+    }
+
+    pub fn create_index(&self, index_name: &str, metadata: &IndexMetadata) -> Result<IndexWriter> {
+        IndexWriter::new(self.dir.path().join("indexes").join(index_name), metadata)
+    }
+
+    pub fn create_keys(&self) -> Result<KeyWriter> {
+        KeyWriter::new(self.dir.path().to_path_buf())
+    }
+
+    pub fn create_tasks_queue(&self) -> Result<TaskWriter> {
+        TaskWriter::new(self.dir.path().join("tasks"))
+    }
+
+    pub fn persist_to(self, mut writer: impl Write) -> Result<()> {
+        let gz_encoder = GzEncoder::new(&mut writer, Compression::default());
+        let mut tar_encoder = tar::Builder::new(gz_encoder);
+        tar_encoder.append_dir_all(".", self.dir.path())?;
+        let gz_encoder = tar_encoder.into_inner()?;
+        gz_encoder.finish()?;
+        writer.flush()?;
+
+        Ok(())
+    }
+}
+
+pub struct KeyWriter {
+    keys: BufWriter<File>,
+}
+
+impl KeyWriter {
+    pub(crate) fn new(path: PathBuf) -> Result<Self> {
+        let keys = File::create(path.join("keys.jsonl"))?;
+        Ok(KeyWriter { keys: BufWriter::new(keys) })
+    }
+
+    pub fn push_key(&mut self, key: &Key) -> Result<()> {
+        self.keys.write_all(&serde_json::to_vec(key)?)?;
+        self.keys.write_all(b"\n")?;
+        Ok(())
+    }
+
+    pub fn flush(mut self) -> Result<()> {
+        self.keys.flush()?;
+        Ok(())
+    }
+}
+
+pub struct TaskWriter {
+    queue: BufWriter<File>,
+    update_files: PathBuf,
+}
+
+impl TaskWriter {
+    pub(crate) fn new(path: PathBuf) -> Result<Self> {
+        std::fs::create_dir(&path)?;
+
+        let queue = File::create(path.join("queue.jsonl"))?;
+        let update_files = path.join("update_files");
+        std::fs::create_dir(&update_files)?;
+
+        Ok(TaskWriter { queue: BufWriter::new(queue), update_files })
+    }
+
+    /// Pushes tasks in the dump.
+    /// If the tasks has an associated `update_file` it'll use the `task_id` as its name.
+    pub fn push_task(&mut self, task: &TaskDump) -> Result<UpdateFile> {
+        self.queue.write_all(&serde_json::to_vec(task)?)?;
+        self.queue.write_all(b"\n")?;
+
+        Ok(UpdateFile::new(self.update_files.join(format!("{}.jsonl", task.uid))))
+    }
+
+    pub fn flush(mut self) -> Result<()> {
+        self.queue.flush()?;
+        Ok(())
+    }
+}
+
+pub struct UpdateFile {
+    path: PathBuf,
+    writer: Option<BufWriter<File>>,
+}
+
+impl UpdateFile {
+    pub(crate) fn new(path: PathBuf) -> UpdateFile {
+        UpdateFile { path, writer: None }
+    }
+
+    pub fn push_document(&mut self, document: &Document) -> Result<()> {
+        if let Some(writer) = self.writer.as_mut() {
+            writer.write_all(&serde_json::to_vec(document)?)?;
+            writer.write_all(b"\n")?;
+        } else {
+            let file = File::create(&self.path).unwrap();
+            self.writer = Some(BufWriter::new(file));
+            self.push_document(document)?;
+        }
+        Ok(())
+    }
+
+    pub fn flush(self) -> Result<()> {
+        if let Some(mut writer) = self.writer {
+            writer.flush()?;
+        }
+        Ok(())
+    }
+}
+
+pub struct IndexWriter {
+    documents: BufWriter<File>,
+    settings: File,
+}
+
+impl IndexWriter {
+    pub(self) fn new(path: PathBuf, metadata: &IndexMetadata) -> Result<Self> {
+        std::fs::create_dir(&path)?;
+
+        let metadata_file = File::create(path.join("metadata.json"))?;
+        serde_json::to_writer(metadata_file, metadata)?;
+
+        let documents = File::create(path.join("documents.jsonl"))?;
+        let settings = File::create(path.join("settings.json"))?;
+
+        Ok(IndexWriter { documents: BufWriter::new(documents), settings })
+    }
+
+    pub fn push_document(&mut self, document: &Map<String, Value>) -> Result<()> {
+        serde_json::to_writer(&mut self.documents, document)?;
+        self.documents.write_all(b"\n")?;
+        Ok(())
+    }
+
+    pub fn flush(&mut self) -> Result<()> {
+        self.documents.flush()?;
+        Ok(())
+    }
+
+    pub fn settings(mut self, settings: &Settings<Checked>) -> Result<()> {
+        self.settings.write_all(&serde_json::to_vec(&settings)?)?;
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+pub(crate) mod test {
+    use std::fmt::Write;
+    use std::io::BufReader;
+    use std::path::Path;
+    use std::str::FromStr;
+
+    use flate2::bufread::GzDecoder;
+    use meili_snap::insta;
+    use meilisearch_types::settings::Unchecked;
+
+    use super::*;
+    use crate::reader::Document;
+    use crate::test::{
+        create_test_api_keys, create_test_documents, create_test_dump, create_test_instance_uid,
+        create_test_settings, create_test_tasks,
+    };
+
+    fn create_directory_hierarchy(dir: &Path) -> String {
+        let mut ret = String::new();
+        writeln!(ret, ".").unwrap();
+        ret.push_str(&_create_directory_hierarchy(dir, 0));
+        ret
+    }
+
+    fn _create_directory_hierarchy(dir: &Path, depth: usize) -> String {
+        let mut ret = String::new();
+
+        // the entries are not guarenteed to be returned in the same order thus we need to sort them.
+        let mut entries =
+            fs::read_dir(dir).unwrap().collect::<std::result::Result<Vec<_>, _>>().unwrap();
+
+        // I want the directories first and then sort by name.
+        entries.sort_by(|a, b| {
+            let (aft, bft) = (a.file_type().unwrap(), b.file_type().unwrap());
+
+            if aft.is_dir() && bft.is_dir() {
+                a.file_name().cmp(&b.file_name())
+            } else if aft.is_file() && bft.is_dir() {
+                std::cmp::Ordering::Greater
+            } else if bft.is_file() && aft.is_dir() {
+                std::cmp::Ordering::Less
+            } else {
+                a.file_name().cmp(&b.file_name())
+            }
+        });
+
+        for (idx, entry) in entries.iter().enumerate() {
+            let mut ident = String::new();
+
+            for _ in 0..depth {
+                ident.push('│');
+                ident.push_str(&" ".repeat(4));
+            }
+            if idx == entries.len() - 1 {
+                ident.push('└');
+            } else {
+                ident.push('├');
+            }
+            ident.push_str(&"-".repeat(4));
+
+            let name = entry.file_name().into_string().unwrap();
+            let file_type = entry.file_type().unwrap();
+            let is_dir = if file_type.is_dir() { "/" } else { "" };
+
+            assert!(!file_type.is_symlink());
+            writeln!(ret, "{ident} {name}{is_dir}").unwrap();
+
+            if file_type.is_dir() {
+                ret.push_str(&_create_directory_hierarchy(&entry.path(), depth + 1));
+            }
+        }
+        ret
+    }
+
+    #[test]
+    #[ignore]
+    fn test_creating_dump() {
+        let file = create_test_dump();
+        let mut file = BufReader::new(file);
+
+        // ============ ensuring we wrote everything in the correct place.
+        let dump = tempfile::tempdir().unwrap();
+
+        let gz = GzDecoder::new(&mut file);
+        let mut tar = tar::Archive::new(gz);
+        tar.unpack(dump.path()).unwrap();
+
+        let dump_path = dump.path();
+
+        // ==== checking global file hierarchy (we want to be sure there isn't too many files or too few)
+        insta::assert_display_snapshot!(create_directory_hierarchy(dump_path), @r###"
+        .
+        ├---- indexes/
+        │    └---- doggos/
+        │    │    ├---- documents.jsonl
+        │    │    ├---- metadata.json
+        │    │    └---- settings.json
+        ├---- tasks/
+        │    ├---- update_files/
+        │    │    └---- 1.jsonl
+        │    └---- queue.jsonl
+        ├---- instance_uid.uuid
+        ├---- keys.jsonl
+        └---- metadata.json
+        "###);
+
+        // ==== checking the top level infos
+        let metadata = fs::read_to_string(dump_path.join("metadata.json")).unwrap();
+        let metadata: Metadata = serde_json::from_str(&metadata).unwrap();
+        insta::assert_json_snapshot!(metadata, { ".dumpDate" => "[date]" }, @r###"
+        {
+          "dumpVersion": "V6",
+          "dbVersion": "0.29.0",
+          "dumpDate": "[date]"
+        }
+        "###);
+
+        let instance_uid = fs::read_to_string(dump_path.join("instance_uid.uuid")).unwrap();
+        assert_eq!(Uuid::from_str(&instance_uid).unwrap(), create_test_instance_uid());
+
+        // ==== checking the index
+        let docs = fs::read_to_string(dump_path.join("indexes/doggos/documents.jsonl")).unwrap();
+        for (document, expected) in docs.lines().zip(create_test_documents()) {
+            assert_eq!(serde_json::from_str::<Map<String, Value>>(document).unwrap(), expected);
+        }
+        let test_settings =
+            fs::read_to_string(dump_path.join("indexes/doggos/settings.json")).unwrap();
+        assert_eq!(
+            serde_json::from_str::<Settings<Unchecked>>(&test_settings).unwrap(),
+            create_test_settings().into_unchecked()
+        );
+        let metadata = fs::read_to_string(dump_path.join("indexes/doggos/metadata.json")).unwrap();
+        let metadata: IndexMetadata = serde_json::from_str(&metadata).unwrap();
+        insta::assert_json_snapshot!(metadata, { ".createdAt" => "[date]", ".updatedAt" => "[date]" }, @r###"
+        {
+          "uid": "doggo",
+          "primaryKey": null,
+          "createdAt": "[date]",
+          "updatedAt": "[date]"
+        }
+        "###);
+
+        // ==== checking the task queue
+        let tasks_queue = fs::read_to_string(dump_path.join("tasks/queue.jsonl")).unwrap();
+        for (task, expected) in tasks_queue.lines().zip(create_test_tasks()) {
+            assert_eq!(serde_json::from_str::<TaskDump>(task).unwrap(), expected.0);
+
+            if let Some(expected_update) = expected.1 {
+                let path = dump_path.join(format!("tasks/update_files/{}.jsonl", expected.0.uid));
+                println!("trying to open {}", path.display());
+                let update = fs::read_to_string(path).unwrap();
+                let documents: Vec<Document> =
+                    update.lines().map(|line| serde_json::from_str(line).unwrap()).collect();
+                assert_eq!(documents, expected_update);
+            }
+        }
+
+        // ==== checking the keys
+        let keys = fs::read_to_string(dump_path.join("keys.jsonl")).unwrap();
+        for (key, expected) in keys.lines().zip(create_test_api_keys()) {
+            assert_eq!(serde_json::from_str::<Key>(key).unwrap(), expected);
+        }
+    }
+}

file-store/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "file-store"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+tempfile = "3.3.0"
+thiserror = "1.0.30"
+uuid = { version = "1.1.2", features = ["serde", "v4"] }
+
+[dev-dependencies]
+faux = "0.1.8"

file-store/src/lib.rs

@@ -0,0 +1,132 @@
+use std::collections::BTreeSet;
+use std::fs::File as StdFile;
+use std::ops::{Deref, DerefMut};
+use std::path::{Path, PathBuf};
+use std::str::FromStr;
+
+use tempfile::NamedTempFile;
+use uuid::Uuid;
+
+const UPDATE_FILES_PATH: &str = "updates/updates_files";
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error(transparent)]
+    IoError(#[from] std::io::Error),
+    #[error(transparent)]
+    PersistError(#[from] tempfile::PersistError),
+}
+
+pub type Result<T> = std::result::Result<T, Error>;
+
+impl Deref for File {
+    type Target = NamedTempFile;
+
+    fn deref(&self) -> &Self::Target {
+        &self.file
+    }
+}
+
+impl DerefMut for File {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.file
+    }
+}
+
+#[cfg_attr(test, faux::create)]
+#[derive(Clone, Debug)]
+pub struct FileStore {
+    path: PathBuf,
+}
+
+#[cfg(not(test))]
+impl FileStore {
+    pub fn new(path: impl AsRef<Path>) -> Result<FileStore> {
+        let path = path.as_ref().to_path_buf();
+        std::fs::create_dir_all(&path)?;
+        Ok(FileStore { path })
+    }
+}
+
+#[cfg_attr(test, faux::methods)]
+impl FileStore {
+    /// Creates a new temporary update file.
+    /// A call to `persist` is needed to persist the file in the database.
+    pub fn new_update(&self) -> Result<(Uuid, File)> {
+        let file = NamedTempFile::new_in(&self.path)?;
+        let uuid = Uuid::new_v4();
+        let path = self.path.join(uuid.to_string());
+        let update_file = File { file, path };
+
+        Ok((uuid, update_file))
+    }
+
+    /// Creates a new temporary update file with the given Uuid.
+    /// A call to `persist` is needed to persist the file in the database.
+    pub fn new_update_with_uuid(&self, uuid: u128) -> Result<(Uuid, File)> {
+        let file = NamedTempFile::new_in(&self.path)?;
+        let uuid = Uuid::from_u128(uuid);
+        let path = self.path.join(uuid.to_string());
+        let update_file = File { file, path };
+
+        Ok((uuid, update_file))
+    }
+
+    /// Returns the file corresponding to the requested uuid.
+    pub fn get_update(&self, uuid: Uuid) -> Result<StdFile> {
+        let path = self.get_update_path(uuid);
+        let file = StdFile::open(path)?;
+        Ok(file)
+    }
+
+    /// Returns the path that correspond to this uuid, the path could not exists.
+    pub fn get_update_path(&self, uuid: Uuid) -> PathBuf {
+        self.path.join(uuid.to_string())
+    }
+
+    /// Copies the content of the update file pointed to by `uuid` to the `dst` directory.
+    pub fn snapshot(&self, uuid: Uuid, dst: impl AsRef<Path>) -> Result<()> {
+        let src = self.path.join(uuid.to_string());
+        let mut dst = dst.as_ref().join(UPDATE_FILES_PATH);
+        std::fs::create_dir_all(&dst)?;
+        dst.push(uuid.to_string());
+        std::fs::copy(src, dst)?;
+        Ok(())
+    }
+
+    pub fn get_size(&self, uuid: Uuid) -> Result<u64> {
+        Ok(self.get_update(uuid)?.metadata()?.len())
+    }
+
+    pub fn delete(&self, uuid: Uuid) -> Result<()> {
+        let path = self.path.join(uuid.to_string());
+        std::fs::remove_file(path)?;
+        Ok(())
+    }
+
+    /// List the Uuids of the files in the FileStore
+    ///
+    /// This function is meant to be used by tests only.
+    #[doc(hidden)]
+    pub fn __all_uuids(&self) -> BTreeSet<Uuid> {
+        let mut uuids = BTreeSet::new();
+        for entry in self.path.read_dir().unwrap() {
+            let entry = entry.unwrap();
+            let uuid = Uuid::from_str(entry.file_name().to_str().unwrap()).unwrap();
+            uuids.insert(uuid);
+        }
+        uuids
+    }
+}
+
+pub struct File {
+    path: PathBuf,
+    file: NamedTempFile,
+}
+
+impl File {
+    pub fn persist(self) -> Result<()> {
+        self.file.persist(&self.path)?;
+        Ok(())
+    }
+}

index-scheduler/Cargo.toml

@@ -0,0 +1,30 @@
+[package]
+name = "index-scheduler"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+anyhow = "1.0.64"
+bincode = "1.3.3"
+csv = "1.1.6"
+derive_builder = "0.11.2"
+dump = { path = "../dump" }
+enum-iterator = "1.1.3"
+file-store = { path = "../file-store" }
+log = "0.4.14"
+meilisearch-types = { path = "../meilisearch-types" }
+roaring = { version = "0.10.0", features = ["serde"] }
+serde = { version = "1.0.136", features = ["derive"] }
+serde_json = { version = "1.0.85", features = ["preserve_order"] }
+synchronoise = "1.0.1"
+tempfile = "3.3.0"
+thiserror = "1.0.30"
+time = { version = "0.3.7", features = ["serde-well-known", "formatting", "parsing", "macros"] }
+uuid = { version = "1.1.2", features = ["serde", "v4"] }
+
+[dev-dependencies]
+big_s = "1.0.2"
+crossbeam = "0.8.2"
+insta = { version = "1.19.1", features = ["json", "redactions"] }
+meili-snap = { path = "../meili-snap" }
+nelson = { git = "https://github.com/meilisearch/nelson.git", rev = "675f13885548fb415ead8fbb447e9e6d9314000a"}

index-scheduler/src/autobatcher.rs

@@ -0,0 +1,727 @@
+/*!
+The autobatcher is responsible for combining the next enqueued
+tasks affecting a single index into a [batch](crate::batch::Batch).
+
+The main function of the autobatcher is [`next_autobatch`].
+*/
+
+use std::ops::ControlFlow::{self, Break, Continue};
+
+use meilisearch_types::milli::update::IndexDocumentsMethod::{
+    self, ReplaceDocuments, UpdateDocuments,
+};
+use meilisearch_types::tasks::TaskId;
+
+use crate::KindWithContent;
+
+/// Succinctly describes a task's [`Kind`](meilisearch_types::tasks::Kind)
+/// for the purpose of simplifying the implementation of the autobatcher.
+///
+/// Only the non-prioritised tasks that can be grouped in a batch have a corresponding [`AutobatchKind`]
+enum AutobatchKind {
+    DocumentImport { method: IndexDocumentsMethod, allow_index_creation: bool },
+    DocumentDeletion,
+    DocumentClear,
+    Settings { allow_index_creation: bool },
+    IndexCreation,
+    IndexDeletion,
+    IndexUpdate,
+    IndexSwap,
+}
+
+impl AutobatchKind {
+    #[rustfmt::skip]
+    fn allow_index_creation(&self) -> Option<bool> {
+        match self {
+            AutobatchKind::DocumentImport { allow_index_creation, .. }
+            | AutobatchKind::Settings { allow_index_creation, .. } => Some(*allow_index_creation),
+            _ => None,
+        }
+    }
+}
+
+impl From<KindWithContent> for AutobatchKind {
+    fn from(kind: KindWithContent) -> Self {
+        match kind {
+            KindWithContent::DocumentAdditionOrUpdate { method, allow_index_creation, .. } => {
+                AutobatchKind::DocumentImport { method, allow_index_creation }
+            }
+            KindWithContent::DocumentDeletion { .. } => AutobatchKind::DocumentDeletion,
+            KindWithContent::DocumentClear { .. } => AutobatchKind::DocumentClear,
+            KindWithContent::SettingsUpdate { allow_index_creation, is_deletion, .. } => {
+                AutobatchKind::Settings {
+                    allow_index_creation: allow_index_creation && !is_deletion,
+                }
+            }
+            KindWithContent::IndexDeletion { .. } => AutobatchKind::IndexDeletion,
+            KindWithContent::IndexCreation { .. } => AutobatchKind::IndexCreation,
+            KindWithContent::IndexUpdate { .. } => AutobatchKind::IndexUpdate,
+            KindWithContent::IndexSwap { .. } => AutobatchKind::IndexSwap,
+            KindWithContent::TaskCancelation { .. }
+            | KindWithContent::TaskDeletion { .. }
+            | KindWithContent::DumpCreation { .. }
+            | KindWithContent::SnapshotCreation => {
+                panic!("The autobatcher should never be called with tasks that don't apply to an index.")
+            }
+        }
+    }
+}
+
+#[derive(Debug)]
+pub enum BatchKind {
+    DocumentClear {
+        ids: Vec<TaskId>,
+    },
+    DocumentImport {
+        method: IndexDocumentsMethod,
+        allow_index_creation: bool,
+        import_ids: Vec<TaskId>,
+    },
+    DocumentDeletion {
+        deletion_ids: Vec<TaskId>,
+    },
+    ClearAndSettings {
+        other: Vec<TaskId>,
+        allow_index_creation: bool,
+        settings_ids: Vec<TaskId>,
+    },
+    SettingsAndDocumentImport {
+        settings_ids: Vec<TaskId>,
+        method: IndexDocumentsMethod,
+        allow_index_creation: bool,
+        import_ids: Vec<TaskId>,
+    },
+    Settings {
+        allow_index_creation: bool,
+        settings_ids: Vec<TaskId>,
+    },
+    IndexDeletion {
+        ids: Vec<TaskId>,
+    },
+    IndexCreation {
+        id: TaskId,
+    },
+    IndexUpdate {
+        id: TaskId,
+    },
+    IndexSwap {
+        id: TaskId,
+    },
+}
+
+impl BatchKind {
+    #[rustfmt::skip]
+    fn allow_index_creation(&self) -> Option<bool> {
+        match self {
+            BatchKind::DocumentImport { allow_index_creation, .. }
+            | BatchKind::ClearAndSettings { allow_index_creation, .. }
+            | BatchKind::SettingsAndDocumentImport { allow_index_creation, .. }
+            | BatchKind::Settings { allow_index_creation, .. } => Some(*allow_index_creation),
+            _ => None,
+        }
+    }
+}
+
+impl BatchKind {
+    /// Returns a `ControlFlow::Break` if you must stop right now.
+    /// The boolean tell you if an index has been created by the batched task.
+    /// To ease the writting of the code. `true` can be returned when you don't need to create an index
+    /// but false can't be returned if you needs to create an index.
+    // TODO use an AutoBatchKind as input
+    pub fn new(
+        task_id: TaskId,
+        kind: KindWithContent,
+    ) -> (ControlFlow<BatchKind, BatchKind>, bool) {
+        use AutobatchKind as K;
+
+        match AutobatchKind::from(kind) {
+            K::IndexCreation => (Break(BatchKind::IndexCreation { id: task_id }), true),
+            K::IndexDeletion => (Break(BatchKind::IndexDeletion { ids: vec![task_id] }), false),
+            K::IndexUpdate => (Break(BatchKind::IndexUpdate { id: task_id }), false),
+            K::IndexSwap => (Break(BatchKind::IndexSwap { id: task_id }), false),
+            K::DocumentClear => (Continue(BatchKind::DocumentClear { ids: vec![task_id] }), false),
+            K::DocumentImport { method, allow_index_creation } => (
+                Continue(BatchKind::DocumentImport {
+                    method,
+                    allow_index_creation,
+                    import_ids: vec![task_id],
+                }),
+                allow_index_creation,
+            ),
+            K::DocumentDeletion => {
+                (Continue(BatchKind::DocumentDeletion { deletion_ids: vec![task_id] }), false)
+            }
+            K::Settings { allow_index_creation } => (
+                Continue(BatchKind::Settings { allow_index_creation, settings_ids: vec![task_id] }),
+                allow_index_creation,
+            ),
+        }
+    }
+
+    /// Returns a `ControlFlow::Break` if you must stop right now.
+    /// The boolean tell you if an index has been created by the batched task.
+    /// To ease the writting of the code. `true` can be returned when you don't need to create an index
+    /// but false can't be returned if you needs to create an index.
+    #[rustfmt::skip]
+    fn accumulate(self, id: TaskId, kind: AutobatchKind, index_already_exists: bool) -> ControlFlow<BatchKind, BatchKind> {
+        use AutobatchKind as K;
+
+        match (self, kind) {
+            // We don't batch any of these operations
+            (this, K::IndexCreation | K::IndexUpdate | K::IndexSwap) => Break(this),
+            // We must not batch tasks that don't have the same index creation rights if the index doesn't already exists.
+            (this, kind) if !index_already_exists && this.allow_index_creation() == Some(false) && kind.allow_index_creation() == Some(true) => {
+                Break(this)
+            },
+            // The index deletion can batch with everything but must stop after
+            (
+                BatchKind::DocumentClear { mut ids }
+                | BatchKind::DocumentDeletion { deletion_ids: mut ids }
+                | BatchKind::DocumentImport { method: _, allow_index_creation: _, import_ids: mut ids }
+                | BatchKind::Settings { allow_index_creation: _, settings_ids: mut ids },
+                K::IndexDeletion,
+            ) => {
+                ids.push(id);
+                Break(BatchKind::IndexDeletion { ids })
+            }
+            (
+                BatchKind::ClearAndSettings { settings_ids: mut ids, allow_index_creation: _, mut other }
+                | BatchKind::SettingsAndDocumentImport { import_ids: mut ids, method: _, allow_index_creation: _, settings_ids: mut other },
+                K::IndexDeletion,
+            ) => {
+                ids.push(id);
+                ids.append(&mut other);
+                Break(BatchKind::IndexDeletion { ids })
+            }
+
+            (
+                BatchKind::DocumentClear { mut ids },
+                K::DocumentClear | K::DocumentDeletion,
+            ) => {
+                ids.push(id);
+                Continue(BatchKind::DocumentClear { ids })
+            }
+            (
+                this @ BatchKind::DocumentClear { .. },
+                K::DocumentImport { .. } | K::Settings { .. },
+            ) => Break(this),
+            (
+                BatchKind::DocumentImport { method: _, allow_index_creation: _, import_ids: mut ids },
+                K::DocumentClear,
+            ) => {
+                ids.push(id);
+                Continue(BatchKind::DocumentClear { ids })
+            }
+
+            // we can autobatch the same kind of document additions / updates
+            (
+                BatchKind::DocumentImport { method: ReplaceDocuments, allow_index_creation, mut import_ids },
+                K::DocumentImport { method: ReplaceDocuments, .. },
+            ) => {
+                import_ids.push(id);
+                Continue(BatchKind::DocumentImport {
+                    method: ReplaceDocuments,
+                    allow_index_creation,
+                    import_ids,
+                })
+            }
+            (
+                BatchKind::DocumentImport { method: UpdateDocuments, allow_index_creation, mut import_ids },
+                K::DocumentImport { method: UpdateDocuments, .. },
+            ) => {
+                import_ids.push(id);
+                Continue(BatchKind::DocumentImport {
+                    method: UpdateDocuments,
+                    allow_index_creation,
+                    import_ids,
+                })
+            }
+
+            // but we can't autobatch documents if it's not the same kind
+            // this match branch MUST be AFTER the previous one
+            (
+                this @ BatchKind::DocumentImport { .. },
+                K::DocumentDeletion | K::DocumentImport { .. },
+            ) => Break(this),
+
+            (
+                BatchKind::DocumentImport { method, allow_index_creation, import_ids },
+                K::Settings { .. },
+            ) => Continue(BatchKind::SettingsAndDocumentImport {
+                settings_ids: vec![id],
+                method,
+                allow_index_creation,
+                import_ids,
+            }),
+
+            (BatchKind::DocumentDeletion { mut deletion_ids }, K::DocumentClear) => {
+                deletion_ids.push(id);
+                Continue(BatchKind::DocumentClear { ids: deletion_ids })
+            }
+            (this @ BatchKind::DocumentDeletion { .. }, K::DocumentImport { .. }) => Break(this),
+            (BatchKind::DocumentDeletion { mut deletion_ids }, K::DocumentDeletion) => {
+                deletion_ids.push(id);
+                Continue(BatchKind::DocumentDeletion { deletion_ids })
+            }
+            (this @ BatchKind::DocumentDeletion { .. }, K::Settings { .. }) => Break(this),
+
+            (
+                BatchKind::Settings { settings_ids, allow_index_creation },
+                K::DocumentClear,
+            ) => Continue(BatchKind::ClearAndSettings {
+                settings_ids,
+                allow_index_creation,
+                other: vec![id],
+            }),
+            (
+                this @ BatchKind::Settings { .. },
+                K::DocumentImport { .. } | K::DocumentDeletion,
+            ) => Break(this),
+            (
+                BatchKind::Settings { mut settings_ids, allow_index_creation },
+                K::Settings { .. },
+            ) => {
+                settings_ids.push(id);
+                Continue(BatchKind::Settings {
+                    allow_index_creation,
+                    settings_ids,
+                })
+            }
+
+            (
+                BatchKind::ClearAndSettings { mut other, settings_ids, allow_index_creation },
+                K::DocumentClear,
+            ) => {
+                other.push(id);
+                Continue(BatchKind::ClearAndSettings {
+                    other,
+                    settings_ids,
+                    allow_index_creation,
+                })
+            }
+            (this @ BatchKind::ClearAndSettings { .. }, K::DocumentImport { .. }) => Break(this),
+            (
+                BatchKind::ClearAndSettings {
+                    mut other,
+                    settings_ids,
+                    allow_index_creation,
+                },
+                K::DocumentDeletion,
+            ) => {
+                other.push(id);
+                Continue(BatchKind::ClearAndSettings {
+                    other,
+                    settings_ids,
+                    allow_index_creation,
+                })
+            }
+            (
+                BatchKind::ClearAndSettings { mut settings_ids, other, allow_index_creation },
+                K::Settings { .. },
+            ) => {
+                settings_ids.push(id);
+                Continue(BatchKind::ClearAndSettings {
+                    other,
+                    settings_ids,
+                    allow_index_creation,
+                })
+            }
+            (
+                BatchKind::SettingsAndDocumentImport { settings_ids, method: _, import_ids: mut other, allow_index_creation },
+                K::DocumentClear,
+            ) => {
+                other.push(id);
+                Continue(BatchKind::ClearAndSettings {
+                    settings_ids,
+                    other,
+                    allow_index_creation,
+                })
+            }
+
+            (
+                BatchKind::SettingsAndDocumentImport { settings_ids, method: ReplaceDocuments, mut import_ids, allow_index_creation },
+                K::DocumentImport { method: ReplaceDocuments, .. },
+            ) => {
+                import_ids.push(id);
+                Continue(BatchKind::SettingsAndDocumentImport {
+                    settings_ids,
+                    method: ReplaceDocuments,
+                    allow_index_creation,
+                    import_ids,
+                })
+            }
+            (
+                BatchKind::SettingsAndDocumentImport { settings_ids, method: UpdateDocuments, allow_index_creation, mut import_ids },
+                K::DocumentImport { method: UpdateDocuments, .. },
+            ) => {
+                import_ids.push(id);
+                Continue(BatchKind::SettingsAndDocumentImport {
+                    settings_ids,
+                    method: UpdateDocuments,
+                    allow_index_creation,
+                    import_ids,
+                })
+            }
+            // But we can't batch a settings and a doc op with another doc op
+            // this MUST be AFTER the two previous branch
+            (
+                this @ BatchKind::SettingsAndDocumentImport { .. },
+                K::DocumentDeletion | K::DocumentImport { .. },
+            ) => Break(this),
+            (
+                BatchKind::SettingsAndDocumentImport { mut settings_ids, method, allow_index_creation, import_ids },
+                K::Settings { .. },
+            ) => {
+                settings_ids.push(id);
+                Continue(BatchKind::SettingsAndDocumentImport {
+                    settings_ids,
+                    method,
+                    allow_index_creation,
+                    import_ids,
+                })
+            }
+            (
+                BatchKind::IndexCreation { .. }
+                | BatchKind::IndexDeletion { .. }
+                | BatchKind::IndexUpdate { .. }
+                | BatchKind::IndexSwap { .. },
+                _,
+            ) => {
+                unreachable!()
+            }
+        }
+    }
+}
+
+/// Create a batch from an ordered list of tasks.
+///
+/// ## Preconditions
+/// 1. The tasks must be enqueued and given in the order in which they were enqueued
+/// 2. The tasks must not be prioritised tasks (e.g. task cancellation, dump, snapshot, task deletion)
+/// 3. The tasks must all be related to the same index
+///
+/// ## Return
+/// `None` if the list of tasks is empty. Otherwise, an [`AutoBatch`] that represents
+/// a subset of the given tasks.
+pub fn autobatch(
+    enqueued: Vec<(TaskId, KindWithContent)>,
+    index_already_exists: bool,
+) -> Option<(BatchKind, bool)> {
+    let mut enqueued = enqueued.into_iter();
+    let (id, kind) = enqueued.next()?;
+
+    // index_exist will keep track of if the index should exist at this point after the tasks we batched.
+    let mut index_exist = index_already_exists;
+
+    let (mut acc, must_create_index) = match BatchKind::new(id, kind) {
+        (Continue(acc), create) => (acc, create),
+        (Break(acc), create) => return Some((acc, create)),
+    };
+
+    // if an index has been created in the previous step we can consider it as existing.
+    index_exist |= must_create_index;
+
+    for (id, kind) in enqueued {
+        acc = match acc.accumulate(id, kind.into(), index_exist) {
+            Continue(acc) => acc,
+            Break(acc) => return Some((acc, must_create_index)),
+        };
+    }
+
+    Some((acc, must_create_index))
+}
+
+#[cfg(test)]
+mod tests {
+    use meilisearch_types::tasks::IndexSwap;
+    use uuid::Uuid;
+
+    use super::*;
+    use crate::debug_snapshot;
+
+    fn autobatch_from(
+        index_already_exists: bool,
+        input: impl IntoIterator<Item = KindWithContent>,
+    ) -> Option<(BatchKind, bool)> {
+        autobatch(
+            input.into_iter().enumerate().map(|(id, kind)| (id as TaskId, kind)).collect(),
+            index_already_exists,
+        )
+    }
+
+    fn doc_imp(method: IndexDocumentsMethod, allow_index_creation: bool) -> KindWithContent {
+        KindWithContent::DocumentAdditionOrUpdate {
+            index_uid: String::from("doggo"),
+            primary_key: None,
+            method,
+            content_file: Uuid::new_v4(),
+            documents_count: 0,
+            allow_index_creation,
+        }
+    }
+
+    fn doc_del() -> KindWithContent {
+        KindWithContent::DocumentDeletion {
+            index_uid: String::from("doggo"),
+            documents_ids: Vec::new(),
+        }
+    }
+
+    fn doc_clr() -> KindWithContent {
+        KindWithContent::DocumentClear { index_uid: String::from("doggo") }
+    }
+
+    fn settings(allow_index_creation: bool) -> KindWithContent {
+        KindWithContent::SettingsUpdate {
+            index_uid: String::from("doggo"),
+            new_settings: Default::default(),
+            is_deletion: false,
+            allow_index_creation,
+        }
+    }
+
+    fn idx_create() -> KindWithContent {
+        KindWithContent::IndexCreation { index_uid: String::from("doggo"), primary_key: None }
+    }
+
+    fn idx_update() -> KindWithContent {
+        KindWithContent::IndexUpdate { index_uid: String::from("doggo"), primary_key: None }
+    }
+
+    fn idx_del() -> KindWithContent {
+        KindWithContent::IndexDeletion { index_uid: String::from("doggo") }
+    }
+
+    fn idx_swap() -> KindWithContent {
+        KindWithContent::IndexSwap {
+            swaps: vec![IndexSwap { indexes: (String::from("doggo"), String::from("catto")) }],
+        }
+    }
+
+    #[test]
+    fn autobatch_simple_operation_together() {
+        // we can autobatch one or multiple `ReplaceDocuments` together.
+        // if the index exists.
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, false)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_imp( ReplaceDocuments, true ), doc_imp(ReplaceDocuments, true )]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0, 1, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, false), doc_imp( ReplaceDocuments, false ), doc_imp(ReplaceDocuments, false )]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0, 1, 2] }, false))");
+
+        // if it doesn't exists.
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, true)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, false)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, true), doc_imp( ReplaceDocuments, true ), doc_imp(ReplaceDocuments, true )]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0, 1, 2] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, false), doc_imp( ReplaceDocuments, true ), doc_imp(ReplaceDocuments, true )]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+
+        // we can autobatch one or multiple `UpdateDocuments` together.
+        // if the index exists.
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), doc_imp(UpdateDocuments, true), doc_imp(UpdateDocuments, true)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0, 1, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, false)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, false), doc_imp(UpdateDocuments, false), doc_imp(UpdateDocuments, false)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: false, import_ids: [0, 1, 2] }, false))");
+
+        // if it doesn't exists.
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, true)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, true), doc_imp(UpdateDocuments, true), doc_imp(UpdateDocuments, true)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0, 1, 2] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, false)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, false), doc_imp(UpdateDocuments, false), doc_imp(UpdateDocuments, false)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: false, import_ids: [0, 1, 2] }, false))");
+
+        // we can autobatch one or multiple DocumentDeletion together
+        debug_snapshot!(autobatch_from(true, [doc_del()]), @"Some((DocumentDeletion { deletion_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_del(), doc_del(), doc_del()]), @"Some((DocumentDeletion { deletion_ids: [0, 1, 2] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_del()]), @"Some((DocumentDeletion { deletion_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_del(), doc_del(), doc_del()]), @"Some((DocumentDeletion { deletion_ids: [0, 1, 2] }, false))");
+
+        // we can autobatch one or multiple Settings together
+        debug_snapshot!(autobatch_from(true, [settings(true)]), @"Some((Settings { allow_index_creation: true, settings_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [settings(true), settings(true), settings(true)]), @"Some((Settings { allow_index_creation: true, settings_ids: [0, 1, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [settings(false)]), @"Some((Settings { allow_index_creation: false, settings_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [settings(false), settings(false), settings(false)]), @"Some((Settings { allow_index_creation: false, settings_ids: [0, 1, 2] }, false))");
+
+        debug_snapshot!(autobatch_from(false, [settings(true)]), @"Some((Settings { allow_index_creation: true, settings_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(false, [settings(true), settings(true), settings(true)]), @"Some((Settings { allow_index_creation: true, settings_ids: [0, 1, 2] }, true))");
+        debug_snapshot!(autobatch_from(false, [settings(false)]), @"Some((Settings { allow_index_creation: false, settings_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [settings(false), settings(false), settings(false)]), @"Some((Settings { allow_index_creation: false, settings_ids: [0, 1, 2] }, false))");
+    }
+
+    #[test]
+    fn simple_document_operation_dont_autobatch_with_other() {
+        // addition, updates and deletion can't batch together
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_imp(UpdateDocuments, true)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_del()]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), doc_imp(ReplaceDocuments, true)]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), doc_del()]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_del(), doc_imp(ReplaceDocuments, true)]), @"Some((DocumentDeletion { deletion_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_del(), doc_imp(UpdateDocuments, true)]), @"Some((DocumentDeletion { deletion_ids: [0] }, false))");
+
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), idx_create()]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), idx_create()]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_del(), idx_create()]), @"Some((DocumentDeletion { deletion_ids: [0] }, false))");
+
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), idx_update()]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), idx_update()]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_del(), idx_update()]), @"Some((DocumentDeletion { deletion_ids: [0] }, false))");
+
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), idx_swap()]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), idx_swap()]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_del(), idx_swap()]), @"Some((DocumentDeletion { deletion_ids: [0] }, false))");
+    }
+
+    #[test]
+    fn document_addition_batch_with_settings() {
+        // simple case
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+
+        // multiple settings and doc addition
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_imp(ReplaceDocuments, true), settings(true), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [2, 3], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_imp(ReplaceDocuments, true), settings(true), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [2, 3], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0, 1] }, true))");
+
+        // addition and setting unordered
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), doc_imp(ReplaceDocuments, true), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1, 3], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), doc_imp(UpdateDocuments, true), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1, 3], method: UpdateDocuments, allow_index_creation: true, import_ids: [0, 2] }, true))");
+
+        // We ensure this kind of batch doesn't batch with forbidden operations
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), doc_imp(UpdateDocuments, true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), doc_imp(ReplaceDocuments, true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), doc_del()]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), doc_del()]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), idx_create()]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), idx_create()]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), idx_update()]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), idx_update()]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), idx_swap()]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), idx_swap()]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: UpdateDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+    }
+
+    #[test]
+    fn clear_and_additions() {
+        // these two doesn't need to batch
+        debug_snapshot!(autobatch_from(true, [doc_clr(), doc_imp(ReplaceDocuments, true)]), @"Some((DocumentClear { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_clr(), doc_imp(UpdateDocuments, true)]), @"Some((DocumentClear { ids: [0] }, false))");
+
+        // Basic use case
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_imp(ReplaceDocuments, true), doc_clr()]), @"Some((DocumentClear { ids: [0, 1, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), doc_imp(UpdateDocuments, true), doc_clr()]), @"Some((DocumentClear { ids: [0, 1, 2] }, true))");
+
+        // This batch kind doesn't mix with other document addition
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_imp(ReplaceDocuments, true), doc_clr(), doc_imp(ReplaceDocuments, true)]), @"Some((DocumentClear { ids: [0, 1, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), doc_imp(UpdateDocuments, true), doc_clr(), doc_imp(UpdateDocuments, true)]), @"Some((DocumentClear { ids: [0, 1, 2] }, true))");
+
+        // But you can batch multiple clear together
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_imp(ReplaceDocuments, true), doc_clr(), doc_clr(), doc_clr()]), @"Some((DocumentClear { ids: [0, 1, 2, 3, 4] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), doc_imp(UpdateDocuments, true), doc_clr(), doc_clr(), doc_clr()]), @"Some((DocumentClear { ids: [0, 1, 2, 3, 4] }, true))");
+    }
+
+    #[test]
+    fn clear_and_additions_and_settings() {
+        // A clear don't need to autobatch the settings that happens AFTER there is no documents
+        debug_snapshot!(autobatch_from(true, [doc_clr(), settings(true)]), @"Some((DocumentClear { ids: [0] }, false))");
+
+        debug_snapshot!(autobatch_from(true, [settings(true), doc_clr(), settings(true)]), @"Some((ClearAndSettings { other: [1], allow_index_creation: true, settings_ids: [0, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), doc_clr()]), @"Some((ClearAndSettings { other: [0, 2], allow_index_creation: true, settings_ids: [1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), doc_clr()]), @"Some((ClearAndSettings { other: [0, 2], allow_index_creation: true, settings_ids: [1] }, true))");
+    }
+
+    #[test]
+    fn anything_and_index_deletion() {
+        // The `IndexDeletion` doesn't batch with anything that happens AFTER.
+        debug_snapshot!(autobatch_from(true, [idx_del(), doc_imp(ReplaceDocuments, true)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [idx_del(), doc_imp(UpdateDocuments, true)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [idx_del(), doc_imp(ReplaceDocuments, false)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [idx_del(), doc_imp(UpdateDocuments, false)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [idx_del(), doc_del()]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [idx_del(), doc_clr()]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [idx_del(), settings(true)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(true, [idx_del(), settings(false)]), @"Some((IndexDeletion { ids: [0] }, false))");
+
+        debug_snapshot!(autobatch_from(false, [idx_del(), doc_imp(ReplaceDocuments, true)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [idx_del(), doc_imp(UpdateDocuments, true)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [idx_del(), doc_imp(ReplaceDocuments, false)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [idx_del(), doc_imp(UpdateDocuments, false)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [idx_del(), doc_del()]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [idx_del(), doc_clr()]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [idx_del(), settings(true)]), @"Some((IndexDeletion { ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [idx_del(), settings(false)]), @"Some((IndexDeletion { ids: [0] }, false))");
+
+        // The index deletion can accept almost any type of `BatchKind` and transform it to an `IndexDeletion`.
+        // First, the basic cases
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, false), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, false), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_del(), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [settings(true), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, true), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, true), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, false), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, false), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_del(), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(false, [settings(true), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(false, [settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 1] }, false))");
+
+        // Then the mixed cases.
+        // The index already exists, whatever is the right of the tasks it shouldn't change the result.
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(true), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments,false), settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, false), settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments,false), settings(false), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, false), settings(false), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments,false), settings(true), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, false), settings(true), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments,false), settings(true), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, false), settings(true), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments,true), settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments,true), settings(false), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(UpdateDocuments, true), settings(false), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, true))");
+
+        // When the index doesn't exists yet it's more complicated.
+        // Either the first task we encounter create it, in which case we can create a big batch with everything.
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, true), settings(true), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, true), settings(true), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, true), settings(true), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, true), settings(true), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, true))");
+        // The right of the tasks following isn't really important.
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments,true), settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, true), settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments,true), settings(false), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, true), settings(false), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, true))");
+        // Or, the second case; the first task doesn't create the index and thus we wants to batch it with only tasks that can't create an index.
+        // that can be a second task that don't have the right to create an index. Or anything that can't create an index like an index deletion, document deletion, document clear, etc.
+        // All theses tasks are going to throw an error `Index doesn't exist` once the batch is processed.
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments,false), settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, false), settings(false), idx_del()]), @"Some((IndexDeletion { ids: [0, 2, 1] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments,false), settings(false), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, false), settings(false), doc_clr(), idx_del()]), @"Some((IndexDeletion { ids: [1, 3, 0, 2] }, false))");
+        // The third and final case is when the first task doesn't create an index but is directly followed by a task creating an index. In this case we can't batch whith what
+        // follows because we first need to process the erronous batch.
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments,false), settings(true), idx_del()]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, false), settings(true), idx_del()]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments,false), settings(true), doc_clr(), idx_del()]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(UpdateDocuments, false), settings(true), doc_clr(), idx_del()]), @"Some((DocumentImport { method: UpdateDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+    }
+
+    #[test]
+    fn allowed_and_disallowed_index_creation() {
+        // `DocumentImport` can't be mixed with those disallowed to do so except if the index already exists.
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, false), doc_imp(ReplaceDocuments, true)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), doc_imp(ReplaceDocuments, true)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, false), doc_imp(ReplaceDocuments, false)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, true), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(true, [doc_imp(ReplaceDocuments, false), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, false), doc_imp(ReplaceDocuments, true)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, true), doc_imp(ReplaceDocuments, true)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: true, import_ids: [0, 1] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, false), doc_imp(ReplaceDocuments, false)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0, 1] }, false))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, true), settings(true)]), @"Some((SettingsAndDocumentImport { settings_ids: [1], method: ReplaceDocuments, allow_index_creation: true, import_ids: [0] }, true))");
+        debug_snapshot!(autobatch_from(false, [doc_imp(ReplaceDocuments, false), settings(true)]), @"Some((DocumentImport { method: ReplaceDocuments, allow_index_creation: false, import_ids: [0] }, false))");
+    }
+}

index-scheduler/src/error.rs

@@ -0,0 +1,77 @@
+use meilisearch_types::error::{Code, ErrorCode};
+use meilisearch_types::{heed, milli};
+use thiserror::Error;
+
+use crate::TaskId;
+
+#[allow(clippy::large_enum_variant)]
+#[derive(Error, Debug)]
+pub enum Error {
+    #[error("Index `{0}` not found.")]
+    IndexNotFound(String),
+    #[error("Index `{0}` already exists.")]
+    IndexAlreadyExists(String),
+    #[error("Corrupted dump.")]
+    CorruptedDump,
+    #[error("Task `{0}` not found.")]
+    TaskNotFound(TaskId),
+    #[error("Query parameters to filter the tasks to delete are missing. Available query parameters are: `uid`, `indexUid`, `status`, `type`.")]
+    TaskDeletionWithEmptyQuery,
+    #[error("Query parameters to filter the tasks to cancel are missing. Available query parameters are: `uid`, `indexUid`, `status`, `type`.")]
+    TaskCancelationWithEmptyQuery,
+
+    #[error(transparent)]
+    Dump(#[from] dump::Error),
+    #[error(transparent)]
+    Heed(#[from] heed::Error),
+    #[error(transparent)]
+    Milli(#[from] milli::Error),
+    #[error("An unexpected crash occurred when processing the task.")]
+    ProcessBatchPanicked,
+    #[error(transparent)]
+    FileStore(#[from] file_store::Error),
+    #[error(transparent)]
+    IoError(#[from] std::io::Error),
+    #[error(transparent)]
+    Persist(#[from] tempfile::PersistError),
+
+    #[error(transparent)]
+    Anyhow(#[from] anyhow::Error),
+
+    // Irrecoverable errors:
+    #[error(transparent)]
+    CreateBatch(Box<Self>),
+    #[error("Corrupted task queue.")]
+    CorruptedTaskQueue,
+    #[error(transparent)]
+    TaskDatabaseUpdate(Box<Self>),
+    #[error(transparent)]
+    HeedTransaction(heed::Error),
+}
+
+impl ErrorCode for Error {
+    fn error_code(&self) -> Code {
+        match self {
+            Error::IndexNotFound(_) => Code::IndexNotFound,
+            Error::IndexAlreadyExists(_) => Code::IndexAlreadyExists,
+            Error::TaskNotFound(_) => Code::TaskNotFound,
+            Error::TaskDeletionWithEmptyQuery => Code::TaskDeletionWithEmptyQuery,
+            Error::TaskCancelationWithEmptyQuery => Code::TaskCancelationWithEmptyQuery,
+
+            Error::Dump(e) => e.error_code(),
+            Error::Milli(e) => e.error_code(),
+            Error::ProcessBatchPanicked => Code::Internal,
+            // TODO: TAMO: are all these errors really internal?
+            Error::Heed(_) => Code::Internal,
+            Error::FileStore(_) => Code::Internal,
+            Error::IoError(_) => Code::Internal,
+            Error::Persist(_) => Code::Internal,
+            Error::Anyhow(_) => Code::Internal,
+            Error::CorruptedTaskQueue => Code::Internal,
+            Error::CorruptedDump => Code::Internal,
+            Error::TaskDatabaseUpdate(_) => Code::Internal,
+            Error::CreateBatch(_) => Code::Internal,
+            Error::HeedTransaction(_) => Code::Internal,
+        }
+    }
+}

index-scheduler/src/index_mapper.rs

@@ -0,0 +1,230 @@
+use std::collections::hash_map::Entry;
+use std::collections::HashMap;
+use std::path::{Path, PathBuf};
+use std::sync::{Arc, RwLock};
+use std::{fs, thread};
+
+use log::error;
+use meilisearch_types::heed::types::{SerdeBincode, Str};
+use meilisearch_types::heed::{Database, Env, EnvOpenOptions, RoTxn, RwTxn};
+use meilisearch_types::milli::update::IndexerConfig;
+use meilisearch_types::milli::Index;
+use uuid::Uuid;
+
+use self::IndexStatus::{Available, BeingDeleted};
+use crate::{Error, Result};
+
+const INDEX_MAPPING: &str = "index-mapping";
+
+/// Structure managing meilisearch's indexes.
+///
+/// It is responsible for:
+/// 1. Creating new indexes
+/// 2. Opening indexes and storing references to these opened indexes
+/// 3. Accessing indexes through their uuid
+/// 4. Mapping a user-defined name to each index uuid.
+#[derive(Clone)]
+pub struct IndexMapper {
+    /// Keep track of the opened indexes. Used mainly by the index resolver.
+    index_map: Arc<RwLock<HashMap<Uuid, IndexStatus>>>,
+
+    // TODO create a UUID Codec that uses the 16 bytes representation
+    /// Map an index name with an index uuid currently available on disk.
+    pub(crate) index_mapping: Database<Str, SerdeBincode<Uuid>>,
+
+    /// Path to the folder where the LMDB environments of each index are.
+    base_path: PathBuf,
+    index_size: usize,
+    pub indexer_config: Arc<IndexerConfig>,
+}
+
+/// Whether the index is available for use or is forbidden to be inserted back in the index map
+#[allow(clippy::large_enum_variant)]
+#[derive(Clone)]
+pub enum IndexStatus {
+    /// Do not insert it back in the index map as it is currently being deleted.
+    BeingDeleted,
+    /// You can use the index without worrying about anything.
+    Available(Index),
+}
+
+impl IndexMapper {
+    pub fn new(
+        env: &Env,
+        base_path: PathBuf,
+        index_size: usize,
+        indexer_config: IndexerConfig,
+    ) -> Result<Self> {
+        Ok(Self {
+            index_map: Arc::default(),
+            index_mapping: env.create_database(Some(INDEX_MAPPING))?,
+            base_path,
+            index_size,
+            indexer_config: Arc::new(indexer_config),
+        })
+    }
+
+    /// Create or open an index in the specified path.
+    /// The path *must* exists or an error will be thrown.
+    fn create_or_open_index(&self, path: &Path) -> Result<Index> {
+        let mut options = EnvOpenOptions::new();
+        options.map_size(self.index_size);
+        options.max_readers(1024);
+        Ok(Index::new(options, path)?)
+    }
+
+    /// Get or create the index.
+    pub fn create_index(&self, mut wtxn: RwTxn, name: &str) -> Result<Index> {
+        match self.index(&wtxn, name) {
+            Ok(index) => {
+                wtxn.commit()?;
+                Ok(index)
+            }
+            Err(Error::IndexNotFound(_)) => {
+                let uuid = Uuid::new_v4();
+                self.index_mapping.put(&mut wtxn, name, &uuid)?;
+
+                let index_path = self.base_path.join(uuid.to_string());
+                fs::create_dir_all(&index_path)?;
+                let index = self.create_or_open_index(&index_path)?;
+
+                wtxn.commit()?;
+                // TODO: it would be better to lazily create the index. But we need an Index::open function for milli.
+                if let Some(BeingDeleted) =
+                    self.index_map.write().unwrap().insert(uuid, Available(index.clone()))
+                {
+                    panic!("Uuid v4 conflict.");
+                }
+
+                Ok(index)
+            }
+            error => error,
+        }
+    }
+
+    /// Removes the index from the mapping table and the in-memory index map
+    /// but keeps the associated tasks.
+    pub fn delete_index(&self, mut wtxn: RwTxn, name: &str) -> Result<()> {
+        let uuid = self
+            .index_mapping
+            .get(&wtxn, name)?
+            .ok_or_else(|| Error::IndexNotFound(name.to_string()))?;
+
+        // Once we retrieved the UUID of the index we remove it from the mapping table.
+        assert!(self.index_mapping.delete(&mut wtxn, name)?);
+
+        wtxn.commit()?;
+        // We remove the index from the in-memory index map.
+        let mut lock = self.index_map.write().unwrap();
+        let closing_event = match lock.insert(uuid, BeingDeleted) {
+            Some(Available(index)) => Some(index.prepare_for_closing()),
+            _ => None,
+        };
+
+        drop(lock);
+
+        let index_map = self.index_map.clone();
+        let index_path = self.base_path.join(uuid.to_string());
+        let index_name = name.to_string();
+        thread::spawn(move || {
+            // We first wait to be sure that the previously opened index is effectively closed.
+            // This can take a lot of time, this is why we do that in a seperate thread.
+            if let Some(closing_event) = closing_event {
+                closing_event.wait();
+            }
+
+            // Then we remove the content from disk.
+            if let Err(e) = fs::remove_dir_all(&index_path) {
+                error!(
+                    "An error happened when deleting the index {} ({}): {}",
+                    index_name, uuid, e
+                );
+            }
+
+            // Finally we remove the entry from the index map.
+            assert!(matches!(index_map.write().unwrap().remove(&uuid), Some(BeingDeleted)));
+        });
+
+        Ok(())
+    }
+
+    pub fn exists(&self, rtxn: &RoTxn, name: &str) -> Result<bool> {
+        Ok(self.index_mapping.get(rtxn, name)?.is_some())
+    }
+
+    /// Return an index, may open it if it wasn't already opened.
+    pub fn index(&self, rtxn: &RoTxn, name: &str) -> Result<Index> {
+        let uuid = self
+            .index_mapping
+            .get(rtxn, name)?
+            .ok_or_else(|| Error::IndexNotFound(name.to_string()))?;
+
+        // we clone here to drop the lock before entering the match
+        let index = self.index_map.read().unwrap().get(&uuid).cloned();
+        let index = match index {
+            Some(Available(index)) => index,
+            Some(BeingDeleted) => return Err(Error::IndexNotFound(name.to_string())),
+            // since we're lazy, it's possible that the index has not been opened yet.
+            None => {
+                let mut index_map = self.index_map.write().unwrap();
+                // between the read lock and the write lock it's not impossible
+                // that someone already opened the index (eg if two search happens
+                // at the same time), thus before opening it we check a second time
+                // if it's not already there.
+                // Since there is a good chance it's not already there we can use
+                // the entry method.
+                match index_map.entry(uuid) {
+                    Entry::Vacant(entry) => {
+                        let index_path = self.base_path.join(uuid.to_string());
+                        let index = self.create_or_open_index(&index_path)?;
+                        entry.insert(Available(index.clone()));
+                        index
+                    }
+                    Entry::Occupied(entry) => match entry.get() {
+                        Available(index) => index.clone(),
+                        BeingDeleted => return Err(Error::IndexNotFound(name.to_string())),
+                    },
+                }
+            }
+        };
+
+        Ok(index)
+    }
+
+    /// Return all indexes, may open them if they weren't already opened.
+    pub fn indexes(&self, rtxn: &RoTxn) -> Result<Vec<(String, Index)>> {
+        self.index_mapping
+            .iter(rtxn)?
+            .map(|ret| {
+                ret.map_err(Error::from).and_then(|(name, _)| {
+                    self.index(rtxn, name).map(|index| (name.to_string(), index))
+                })
+            })
+            .collect()
+    }
+
+    /// Swap two index names.
+    pub fn swap(&self, wtxn: &mut RwTxn, lhs: &str, rhs: &str) -> Result<()> {
+        let lhs_uuid = self
+            .index_mapping
+            .get(wtxn, lhs)?
+            .ok_or_else(|| Error::IndexNotFound(lhs.to_string()))?;
+        let rhs_uuid = self
+            .index_mapping
+            .get(wtxn, rhs)?
+            .ok_or_else(|| Error::IndexNotFound(rhs.to_string()))?;
+
+        self.index_mapping.put(wtxn, lhs, &rhs_uuid)?;
+        self.index_mapping.put(wtxn, rhs, &lhs_uuid)?;
+
+        Ok(())
+    }
+
+    pub fn index_exists(&self, rtxn: &RoTxn, name: &str) -> Result<bool> {
+        Ok(self.index_mapping.get(rtxn, name)?.is_some())
+    }
+
+    pub fn indexer_config(&self) -> &IndexerConfig {
+        &self.indexer_config
+    }
+}

index-scheduler/src/insta_snapshot.rs

@@ -0,0 +1,238 @@
+use std::fmt::Write;
+
+use meilisearch_types::heed::types::{OwnedType, SerdeBincode, SerdeJson, Str};
+use meilisearch_types::heed::{Database, RoTxn};
+use meilisearch_types::milli::{CboRoaringBitmapCodec, RoaringBitmapCodec, BEU32};
+use meilisearch_types::tasks::{Details, Task};
+use roaring::RoaringBitmap;
+
+use crate::index_mapper::IndexMapper;
+use crate::{IndexScheduler, Kind, Status, BEI128};
+
+pub fn snapshot_index_scheduler(scheduler: &IndexScheduler) -> String {
+    let IndexScheduler {
+        autobatching_enabled,
+        must_stop_processing: _,
+        processing_tasks,
+        file_store,
+        env,
+        all_tasks,
+        status,
+        kind,
+        index_tasks,
+        enqueued_at,
+        started_at,
+        finished_at,
+        index_mapper,
+        wake_up: _,
+        dumps_path: _,
+        snapshots_path: _,
+        auth_path: _,
+        version_file_path: _,
+        test_breakpoint_sdr: _,
+        planned_failures: _,
+        run_loop_iteration: _,
+    } = scheduler;
+
+    let rtxn = env.read_txn().unwrap();
+
+    let mut snap = String::new();
+
+    let processing_tasks = processing_tasks.read().unwrap().processing.clone();
+    snap.push_str(&format!("### Autobatching Enabled = {autobatching_enabled}\n"));
+    snap.push_str("### Processing Tasks:\n");
+    snap.push_str(&snapshot_bitmap(&processing_tasks));
+    snap.push_str("\n----------------------------------------------------------------------\n");
+
+    snap.push_str("### All Tasks:\n");
+    snap.push_str(&snapshot_all_tasks(&rtxn, *all_tasks));
+    snap.push_str("----------------------------------------------------------------------\n");
+
+    snap.push_str("### Status:\n");
+    snap.push_str(&snapshot_status(&rtxn, *status));
+    snap.push_str("----------------------------------------------------------------------\n");
+
+    snap.push_str("### Kind:\n");
+    snap.push_str(&snapshot_kind(&rtxn, *kind));
+    snap.push_str("----------------------------------------------------------------------\n");
+
+    snap.push_str("### Index Tasks:\n");
+    snap.push_str(&snapshot_index_tasks(&rtxn, *index_tasks));
+    snap.push_str("----------------------------------------------------------------------\n");
+
+    snap.push_str("### Index Mapper:\n");
+    snap.push_str(&snapshot_index_mapper(&rtxn, index_mapper));
+    snap.push_str("\n----------------------------------------------------------------------\n");
+
+    snap.push_str("### Enqueued At:\n");
+    snap.push_str(&snapshot_date_db(&rtxn, *enqueued_at));
+    snap.push_str("----------------------------------------------------------------------\n");
+
+    snap.push_str("### Started At:\n");
+    snap.push_str(&snapshot_date_db(&rtxn, *started_at));
+    snap.push_str("----------------------------------------------------------------------\n");
+
+    snap.push_str("### Finished At:\n");
+    snap.push_str(&snapshot_date_db(&rtxn, *finished_at));
+    snap.push_str("----------------------------------------------------------------------\n");
+
+    snap.push_str("### File Store:\n");
+    snap.push_str(&snapshot_file_store(file_store));
+    snap.push_str("\n----------------------------------------------------------------------\n");
+
+    snap
+}
+
+pub fn snapshot_file_store(file_store: &file_store::FileStore) -> String {
+    let mut snap = String::new();
+    for uuid in file_store.__all_uuids() {
+        snap.push_str(&format!("{uuid}\n"));
+    }
+    snap
+}
+
+pub fn snapshot_bitmap(r: &RoaringBitmap) -> String {
+    let mut snap = String::new();
+    snap.push('[');
+    for x in r {
+        snap.push_str(&format!("{x},"));
+    }
+    snap.push(']');
+    snap
+}
+
+pub fn snapshot_all_tasks(rtxn: &RoTxn, db: Database<OwnedType<BEU32>, SerdeJson<Task>>) -> String {
+    let mut snap = String::new();
+    let iter = db.iter(rtxn).unwrap();
+    for next in iter {
+        let (task_id, task) = next.unwrap();
+        snap.push_str(&format!("{task_id} {}\n", snapshot_task(&task)));
+    }
+    snap
+}
+
+pub fn snapshot_date_db(
+    rtxn: &RoTxn,
+    db: Database<OwnedType<BEI128>, CboRoaringBitmapCodec>,
+) -> String {
+    let mut snap = String::new();
+    let iter = db.iter(rtxn).unwrap();
+    for next in iter {
+        let (_timestamp, task_ids) = next.unwrap();
+        snap.push_str(&format!("[timestamp] {}\n", snapshot_bitmap(&task_ids)));
+    }
+    snap
+}
+
+pub fn snapshot_task(task: &Task) -> String {
+    let mut snap = String::new();
+    let Task {
+        uid,
+        enqueued_at: _,
+        started_at: _,
+        finished_at: _,
+        error,
+        canceled_by,
+        details,
+        status,
+        kind,
+    } = task;
+    snap.push('{');
+    snap.push_str(&format!("uid: {uid}, "));
+    snap.push_str(&format!("status: {status}, "));
+    if let Some(canceled_by) = canceled_by {
+        snap.push_str(&format!("canceled_by: {canceled_by}, "));
+    }
+    if let Some(error) = error {
+        snap.push_str(&format!("error: {error:?}, "));
+    }
+    if let Some(details) = details {
+        snap.push_str(&format!("details: {}, ", &snapshot_details(details)));
+    }
+    snap.push_str(&format!("kind: {kind:?}"));
+
+    snap.push('}');
+    snap
+}
+
+fn snapshot_details(d: &Details) -> String {
+    match d {
+        Details::DocumentAdditionOrUpdate {
+            received_documents,
+            indexed_documents,
+        } => {
+            format!("{{ received_documents: {received_documents}, indexed_documents: {indexed_documents:?} }}")
+        }
+        Details::SettingsUpdate { settings } => {
+            format!("{{ settings: {settings:?} }}")
+        }
+        Details::IndexInfo { primary_key } => {
+            format!("{{ primary_key: {primary_key:?} }}")
+        }
+        Details::DocumentDeletion {
+            matched_documents: received_document_ids,
+            deleted_documents,
+        } => format!("{{ received_document_ids: {received_document_ids}, deleted_documents: {deleted_documents:?} }}"),
+        Details::ClearAll { deleted_documents } => {
+            format!("{{ deleted_documents: {deleted_documents:?} }}")
+        },
+        Details::TaskCancelation {
+            matched_tasks,
+            canceled_tasks,
+            original_query,
+        } => {
+            format!("{{ matched_tasks: {matched_tasks:?}, canceled_tasks: {canceled_tasks:?}, original_query: {original_query:?} }}")
+        }
+        Details::TaskDeletion {
+            matched_tasks,
+            deleted_tasks,
+            original_query,
+        } => {
+            format!("{{ matched_tasks: {matched_tasks:?}, deleted_tasks: {deleted_tasks:?}, original_query: {original_query:?} }}")
+        },
+        Details::Dump { dump_uid } => {
+            format!("{{ dump_uid: {dump_uid:?} }}")
+        },
+        Details::IndexSwap { swaps } => {
+            format!("{{ swaps: {swaps:?} }}")
+        }
+    }
+}
+
+pub fn snapshot_status(
+    rtxn: &RoTxn,
+    db: Database<SerdeBincode<Status>, RoaringBitmapCodec>,
+) -> String {
+    let mut snap = String::new();
+    let iter = db.iter(rtxn).unwrap();
+    for next in iter {
+        let (status, task_ids) = next.unwrap();
+        writeln!(snap, "{status} {}", snapshot_bitmap(&task_ids)).unwrap();
+    }
+    snap
+}
+pub fn snapshot_kind(rtxn: &RoTxn, db: Database<SerdeBincode<Kind>, RoaringBitmapCodec>) -> String {
+    let mut snap = String::new();
+    let iter = db.iter(rtxn).unwrap();
+    for next in iter {
+        let (kind, task_ids) = next.unwrap();
+        let kind = serde_json::to_string(&kind).unwrap();
+        writeln!(snap, "{kind} {}", snapshot_bitmap(&task_ids)).unwrap();
+    }
+    snap
+}
+
+pub fn snapshot_index_tasks(rtxn: &RoTxn, db: Database<Str, RoaringBitmapCodec>) -> String {
+    let mut snap = String::new();
+    let iter = db.iter(rtxn).unwrap();
+    for next in iter {
+        let (index, task_ids) = next.unwrap();
+        writeln!(snap, "{index} {}", snapshot_bitmap(&task_ids)).unwrap();
+    }
+    snap
+}
+
+pub fn snapshot_index_mapper(rtxn: &RoTxn, mapper: &IndexMapper) -> String {
+    let names = mapper.indexes(rtxn).unwrap().into_iter().map(|(n, _)| n).collect::<Vec<_>>();
+    format!("{names:?}")
+}

index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/cancel_processed.snap

@@ -0,0 +1,41 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: canceled, canceled_by: 1, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: succeeded, details: { matched_tasks: 1, canceled_tasks: Some(1), original_query: "test_query" }, kind: TaskCancelation { query: "test_query", tasks: RoaringBitmap<[0]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [1,]
+canceled [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+"taskCancelation" [1,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/initial_tasks_enqueued.snap

@@ -0,0 +1,37 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: enqueued, details: { matched_tasks: 1, canceled_tasks: None, original_query: "test_query" }, kind: TaskCancelation { query: "test_query", tasks: RoaringBitmap<[0]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+"taskCancelation" [1,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/cancel_processed.snap

@@ -0,0 +1,49 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: canceled, canceled_by: 3, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "beavero", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: canceled, canceled_by: 3, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "wolfo", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000002, documents_count: 1, allow_index_creation: true }}
+3 {uid: 3, status: succeeded, details: { matched_tasks: 3, canceled_tasks: Some(2), original_query: "test_query" }, kind: TaskCancelation { query: "test_query", tasks: RoaringBitmap<[0, 1, 2]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,3,]
+canceled [1,2,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,1,2,]
+"taskCancelation" [3,]
+----------------------------------------------------------------------
+### Index Tasks:
+beavero [1,]
+catto [0,]
+wolfo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+["beavero", "catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/first_task_processed.snap

@@ -0,0 +1,44 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "beavero", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "wolfo", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000002, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [1,2,]
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,1,2,]
+----------------------------------------------------------------------
+### Index Tasks:
+beavero [1,]
+catto [0,]
+wolfo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000001
+00000000-0000-0000-0000-000000000002
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/processing_second_task_cancel_enqueued.snap

@@ -0,0 +1,47 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[1,]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "beavero", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "wolfo", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000002, documents_count: 1, allow_index_creation: true }}
+3 {uid: 3, status: enqueued, details: { matched_tasks: 3, canceled_tasks: None, original_query: "test_query" }, kind: TaskCancelation { query: "test_query", tasks: RoaringBitmap<[0, 1, 2]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued [1,2,3,]
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,1,2,]
+"taskCancelation" [3,]
+----------------------------------------------------------------------
+### Index Tasks:
+beavero [1,]
+catto [0,]
+wolfo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000001
+00000000-0000-0000-0000-000000000002
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_processed.snap

@@ -0,0 +1,41 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: canceled, canceled_by: 1, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: succeeded, details: { matched_tasks: 1, canceled_tasks: Some(1), original_query: "test_query" }, kind: TaskCancelation { query: "test_query", tasks: RoaringBitmap<[0]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [1,]
+canceled [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+"taskCancelation" [1,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/cancel_processing_task/initial_task_processing.snap

@@ -0,0 +1,34 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[0,]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/cancel_processed.snap

@@ -0,0 +1,41 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: succeeded, details: { matched_tasks: 1, canceled_tasks: Some(0), original_query: "test_query" }, kind: TaskCancelation { query: "test_query", tasks: RoaringBitmap<[0]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+"taskCancelation" [1,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/initial_task_processed.snap

@@ -0,0 +1,36 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/document_addition/1.snap

@@ -0,0 +1,34 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/document_addition/2.snap

@@ -0,0 +1,34 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[0,]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/document_addition/3.snap

@@ -0,0 +1,36 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+["doggos"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/1.snap

@@ -0,0 +1,40 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: None }, kind: IndexCreation { index_uid: "doggos", primary_key: None }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: enqueued, kind: IndexDeletion { index_uid: "doggos" }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,]
+"indexCreation" [0,]
+"indexDeletion" [2,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,1,2,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/2.snap

@@ -0,0 +1,44 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { primary_key: None }, kind: IndexCreation { index_uid: "doggos", primary_key: None }}
+1 {uid: 1, status: succeeded, details: { received_documents: 1, indexed_documents: Some(0) }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: succeeded, details: { deleted_documents: Some(0) }, kind: IndexDeletion { index_uid: "doggos" }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,2,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,]
+"indexCreation" [0,]
+"indexDeletion" [2,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,1,2,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [1,2,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,2,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/1.snap

@@ -0,0 +1,37 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: enqueued, kind: IndexDeletion { index_uid: "doggos" }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+"indexDeletion" [1,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,1,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/2.snap

@@ -0,0 +1,39 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(0) }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: succeeded, details: { deleted_documents: Some(0) }, kind: IndexDeletion { index_uid: "doggos" }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+"indexDeletion" [1,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,1,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,1,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,1,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/fail_in_create_batch_for_index_creation/1.snap

@@ -0,0 +1,33 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[0,]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_batch_created.snap

@@ -0,0 +1,34 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[0,]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_failed.snap

@@ -0,0 +1,36 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: failed, error: ResponseError { code: 200, message: "Corrupted task queue.", error_code: "internal", error_type: "internal", error_link: "https://docs.meilisearch.com/errors#internal" }, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+failed [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/index_creation_failed.snap

@@ -0,0 +1,36 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: failed, error: ResponseError { code: 200, message: "Corrupted task queue.", error_code: "internal", error_type: "internal", error_link: "https://docs.meilisearch.com/errors#internal" }, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+failed [0,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/document_addition_succeeded_but_index_scheduler_not_updated.snap

@@ -0,0 +1,34 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/second_iteration.snap

@@ -0,0 +1,36 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+["doggos"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/1.snap

@@ -0,0 +1,39 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[0,]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "index_a", primary_key: Some("id") }}
+1 {uid: 1, status: enqueued, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "index_b", primary_key: Some("id") }}
+2 {uid: 2, status: enqueued, kind: IndexDeletion { index_uid: "index_a" }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,]
+"indexDeletion" [2,]
+----------------------------------------------------------------------
+### Index Tasks:
+index_a [0,2,]
+index_b [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/index_creation_failed.snap

@@ -0,0 +1,36 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: failed, error: ResponseError { code: 200, message: "An unexpected crash occurred when processing the task.", error_code: "internal", error_type: "internal", error_link: "https://docs.meilisearch.com/errors#internal" }, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+failed [0,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/query_processing_tasks/end.snap

@@ -0,0 +1,47 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+1 {uid: 1, status: succeeded, details: { primary_key: Some("sheep") }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("sheep") }}
+2 {uid: 2, status: failed, error: ResponseError { code: 200, message: "Corrupted task queue.", error_code: "internal", error_type: "internal", error_link: "https://docs.meilisearch.com/errors#internal" }, details: { primary_key: Some("fish") }, kind: IndexCreation { index_uid: "whalo", primary_key: Some("fish") }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,]
+failed [2,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,2,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+doggo [1,]
+whalo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto", "doggo"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/query_processing_tasks/start.snap

@@ -0,0 +1,39 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+1 {uid: 1, status: enqueued, details: { primary_key: Some("sheep") }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("sheep") }}
+2 {uid: 2, status: enqueued, details: { primary_key: Some("fish") }, kind: IndexCreation { index_uid: "whalo", primary_key: Some("fish") }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,2,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+doggo [1,]
+whalo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/finished.snap

@@ -0,0 +1,46 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { primary_key: Some("bone") }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("bone") }}
+1 {uid: 1, status: succeeded, details: { primary_key: Some("plankton") }, kind: IndexCreation { index_uid: "whalo", primary_key: Some("plankton") }}
+2 {uid: 2, status: succeeded, details: { primary_key: Some("his_own_vomit") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("his_own_vomit") }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,2,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,2,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [2,]
+doggo [0,]
+whalo [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto", "doggo", "whalo"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/start.snap

@@ -0,0 +1,39 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("bone") }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("bone") }}
+1 {uid: 1, status: enqueued, details: { primary_key: Some("plankton") }, kind: IndexCreation { index_uid: "whalo", primary_key: Some("plankton") }}
+2 {uid: 2, status: enqueued, details: { primary_key: Some("his_own_vomit") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("his_own_vomit") }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,2,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [2,]
+doggo [0,]
+whalo [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/register/1.snap

@@ -0,0 +1,44 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+1 {uid: 1, status: enqueued, details: { received_documents: 12, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 12, allow_index_creation: true }}
+2 {uid: 2, status: enqueued, details: { received_documents: 50, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 50, allow_index_creation: true }}
+3 {uid: 3, status: enqueued, details: { received_documents: 5000, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000002, documents_count: 5000, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,3,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,2,3,]
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,1,2,]
+doggo [3,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
+00000000-0000-0000-0000-000000000002
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_processed.snap

@@ -0,0 +1,56 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "b", primary_key: Some("id") }}
+1 {uid: 1, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "a", primary_key: Some("id") }}
+2 {uid: 2, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "d", primary_key: Some("id") }}
+3 {uid: 3, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "c", primary_key: Some("id") }}
+4 {uid: 4, status: succeeded, details: { swaps: [IndexSwap { indexes: ("a", "b") }, IndexSwap { indexes: ("c", "d") }] }, kind: IndexSwap { swaps: [IndexSwap { indexes: ("a", "b") }, IndexSwap { indexes: ("c", "d") }] }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,2,3,4,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,2,3,]
+"indexSwap" [4,]
+----------------------------------------------------------------------
+### Index Tasks:
+a [1,4,]
+b [0,4,]
+c [3,4,]
+d [2,4,]
+----------------------------------------------------------------------
+### Index Mapper:
+["a", "b", "c", "d"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/swap_indexes/initial_tasks_processed.snap

@@ -0,0 +1,51 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "a", primary_key: Some("id") }}
+1 {uid: 1, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "b", primary_key: Some("id") }}
+2 {uid: 2, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "c", primary_key: Some("id") }}
+3 {uid: 3, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "d", primary_key: Some("id") }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,2,3,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,2,3,]
+----------------------------------------------------------------------
+### Index Tasks:
+a [0,]
+b [1,]
+c [2,]
+d [3,]
+----------------------------------------------------------------------
+### Index Mapper:
+["a", "b", "c", "d"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/swap_indexes/second_swap_processed.snap

@@ -0,0 +1,60 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "b", primary_key: Some("id") }}
+1 {uid: 1, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "c", primary_key: Some("id") }}
+2 {uid: 2, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "d", primary_key: Some("id") }}
+3 {uid: 3, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "a", primary_key: Some("id") }}
+4 {uid: 4, status: succeeded, details: { swaps: [IndexSwap { indexes: ("c", "b") }, IndexSwap { indexes: ("a", "d") }] }, kind: IndexSwap { swaps: [IndexSwap { indexes: ("c", "b") }, IndexSwap { indexes: ("a", "d") }] }}
+5 {uid: 5, status: succeeded, details: { swaps: [IndexSwap { indexes: ("a", "c") }] }, kind: IndexSwap { swaps: [IndexSwap { indexes: ("a", "c") }] }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,2,3,4,5,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,2,3,]
+"indexSwap" [4,5,]
+----------------------------------------------------------------------
+### Index Tasks:
+a [3,4,5,]
+b [0,4,]
+c [1,4,5,]
+d [2,4,]
+----------------------------------------------------------------------
+### Index Mapper:
+["a", "b", "c", "d"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+[timestamp] [5,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+[timestamp] [5,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+[timestamp] [5,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/swap_indexes/third_empty_swap_processed.snap

@@ -0,0 +1,64 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "b", primary_key: Some("id") }}
+1 {uid: 1, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "c", primary_key: Some("id") }}
+2 {uid: 2, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "d", primary_key: Some("id") }}
+3 {uid: 3, status: succeeded, details: { primary_key: Some("id") }, kind: IndexCreation { index_uid: "a", primary_key: Some("id") }}
+4 {uid: 4, status: succeeded, details: { swaps: [IndexSwap { indexes: ("c", "b") }, IndexSwap { indexes: ("a", "d") }] }, kind: IndexSwap { swaps: [IndexSwap { indexes: ("c", "b") }, IndexSwap { indexes: ("a", "d") }] }}
+5 {uid: 5, status: succeeded, details: { swaps: [IndexSwap { indexes: ("a", "c") }] }, kind: IndexSwap { swaps: [IndexSwap { indexes: ("a", "c") }] }}
+6 {uid: 6, status: succeeded, details: { swaps: [] }, kind: IndexSwap { swaps: [] }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,1,2,3,4,5,6,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,1,2,3,]
+"indexSwap" [4,5,6,]
+----------------------------------------------------------------------
+### Index Tasks:
+a [3,4,5,]
+b [0,4,]
+c [1,4,5,]
+d [2,4,]
+----------------------------------------------------------------------
+### Index Mapper:
+["a", "b", "c", "d"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+[timestamp] [5,]
+[timestamp] [6,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+[timestamp] [5,]
+[timestamp] [6,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+[timestamp] [5,]
+[timestamp] [6,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_enqueued.snap

@@ -0,0 +1,38 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,1,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+doggo [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_processed.snap

@@ -0,0 +1,40 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [1,]
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,1,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+doggo [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/task_deletion_processed.snap

@@ -0,0 +1,44 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: succeeded, details: { matched_tasks: 1, deleted_tasks: Some(1), original_query: "test_query" }, kind: TaskDeletion { query: "test_query", tasks: RoaringBitmap<[0]> }}
+3 {uid: 3, status: succeeded, details: { matched_tasks: 1, deleted_tasks: Some(0), original_query: "test_query" }, kind: TaskDeletion { query: "test_query", tasks: RoaringBitmap<[0]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued [1,]
+succeeded [2,3,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,]
+"taskDeletion" [2,3,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggo [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_enqueued.snap

@@ -0,0 +1,38 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,1,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+doggo [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_processed.snap

@@ -0,0 +1,40 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { received_documents: 1, indexed_documents: Some(1) }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [1,]
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [0,1,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,]
+doggo [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/task_deletion_processed.snap

@@ -0,0 +1,40 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: succeeded, details: { matched_tasks: 1, deleted_tasks: Some(1), original_query: "test_query" }, kind: TaskDeletion { query: "test_query", tasks: RoaringBitmap<[0]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued [1,]
+succeeded [2,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,]
+"taskDeletion" [2,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggo [1,]
+----------------------------------------------------------------------
+### Index Mapper:
+["catto"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [2,]
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/initial_tasks_enqueued.snap

@@ -0,0 +1,41 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,2,]
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,1,]
+doggo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_done.snap

@@ -0,0 +1,47 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+3 {uid: 3, status: succeeded, details: { matched_tasks: 2, deleted_tasks: Some(0), original_query: "test_query" }, kind: TaskDeletion { query: "test_query", tasks: RoaringBitmap<[0, 1]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,]
+succeeded [3,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,2,]
+"indexCreation" [0,]
+"taskDeletion" [3,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,1,]
+doggo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [3,]
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_enqueued.snap

@@ -0,0 +1,44 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+3 {uid: 3, status: enqueued, details: { matched_tasks: 2, deleted_tasks: None, original_query: "test_query" }, kind: TaskDeletion { query: "test_query", tasks: RoaringBitmap<[0, 1]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,3,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,2,]
+"indexCreation" [0,]
+"taskDeletion" [3,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,1,]
+doggo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_processing.snap

@@ -0,0 +1,44 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[3,]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: Some("mouse") }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "catto", primary_key: None, method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: true }}
+2 {uid: 2, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggo", primary_key: Some("bone"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: true }}
+3 {uid: 3, status: enqueued, details: { matched_tasks: 2, deleted_tasks: None, original_query: "test_query" }, kind: TaskDeletion { query: "test_query", tasks: RoaringBitmap<[0, 1]> }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,1,2,3,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,2,]
+"indexCreation" [0,]
+"taskDeletion" [3,]
+----------------------------------------------------------------------
+### Index Tasks:
+catto [0,1,]
+doggo [2,]
+----------------------------------------------------------------------
+### Index Mapper:
+[]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
+
+----------------------------------------------------------------------
+

index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/1.snap

@@ -0,0 +1,67 @@
+---
+source: index-scheduler/src/lib.rs
+---
+### Autobatching Enabled = true
+### Processing Tasks:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: succeeded, details: { primary_key: None }, kind: IndexCreation { index_uid: "doggos", primary_key: None }}
+1 {uid: 1, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000000, documents_count: 1, allow_index_creation: false }}
+2 {uid: 2, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000001, documents_count: 1, allow_index_creation: false }}
+3 {uid: 3, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000002, documents_count: 1, allow_index_creation: false }}
+4 {uid: 4, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000003, documents_count: 1, allow_index_creation: false }}
+5 {uid: 5, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000004, documents_count: 1, allow_index_creation: false }}
+6 {uid: 6, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000005, documents_count: 1, allow_index_creation: false }}
+7 {uid: 7, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000006, documents_count: 1, allow_index_creation: false }}
+8 {uid: 8, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000007, documents_count: 1, allow_index_creation: false }}
+9 {uid: 9, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000008, documents_count: 1, allow_index_creation: false }}
+10 {uid: 10, status: enqueued, details: { received_documents: 1, indexed_documents: None }, kind: DocumentAdditionOrUpdate { index_uid: "doggos", primary_key: Some("id"), method: ReplaceDocuments, content_file: 00000000-0000-0000-0000-000000000009, documents_count: 1, allow_index_creation: false }}
+----------------------------------------------------------------------
+### Status:
+enqueued [1,2,3,4,5,6,7,8,9,10,]
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"documentAdditionOrUpdate" [1,2,3,4,5,6,7,8,9,10,]
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,1,2,3,4,5,6,7,8,9,10,]
+----------------------------------------------------------------------
+### Index Mapper:
+["doggos"]
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+[timestamp] [1,]
+[timestamp] [2,]
+[timestamp] [3,]
+[timestamp] [4,]
+[timestamp] [5,]
+[timestamp] [6,]
+[timestamp] [7,]
+[timestamp] [8,]
+[timestamp] [9,]
+[timestamp] [10,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
+00000000-0000-0000-0000-000000000002
+00000000-0000-0000-0000-000000000003
+00000000-0000-0000-0000-000000000004
+00000000-0000-0000-0000-000000000005
+00000000-0000-0000-0000-000000000006
+00000000-0000-0000-0000-000000000007
+00000000-0000-0000-0000-000000000008
+00000000-0000-0000-0000-000000000009
+
+----------------------------------------------------------------------
+