Introduce a new meilitool to help the cloud team

Cargo.lock

@@ -310,16 +310,15 @@ checksum = "4b46cbb362ab8752921c97e041f5e366ee6297bd428a31275b9fcf1e380f7299"
 
 [[package]]
 name = "anstream"
-version = "0.3.2"
+version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0ca84f3628370c59db74ee214b3263d58f9aadd9b4fe7e711fd87dc452b7f163"
+checksum = "2ab91ebe16eb252986481c5b62f6098f3b698a45e34b5b98200cf20dd2484a44"
 dependencies = [
  "anstyle",
  "anstyle-parse",
  "anstyle-query",
  "anstyle-wincon",
  "colorchoice",
- "is-terminal",
  "utf8parse",
 ]
 
@@ -349,9 +348,9 @@ dependencies = [
 
 [[package]]
 name = "anstyle-wincon"
-version = "1.0.1"
+version = "3.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "180abfa45703aebe0093f79badacc01b8fd4ea2e35118747e5811127f926e188"
+checksum = "f0699d10d2f4d628a98ee7b57b289abbc98ff3bad977cb3152709d4bf2330628"
 dependencies = [
  "anstyle",
  "windows-sys 0.48.0",
@@ -359,9 +358,9 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.72"
+version = "1.0.75"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3b13c32d80ecc7ab747b80c3784bce54ee8a7a0cc4fbda9bf4cda2cf6fe90854"
+checksum = "a4668cab20f66d8d020e1fbc0ebe47217433c1b6c8f2040faf858554e394ace6"
 dependencies = [
  "backtrace",
 ]
@@ -777,20 +776,19 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "4.3.21"
+version = "4.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c27cdf28c0f604ba3f512b0c9a409f8de8513e4816705deb0498b627e7c3a3fd"
+checksum = "ac495e00dcec98c83465d5ad66c5c4fabd652fd6686e7c6269b117e729a6f17b"
 dependencies = [
  "clap_builder",
  "clap_derive",
- "once_cell",
 ]
 
 [[package]]
 name = "clap_builder"
-version = "4.3.21"
+version = "4.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "08a9f1ab5e9f01a9b81f202e8562eb9a10de70abf9eaeac1be465c28b75aa4aa"
+checksum = "c77ed9a32a62e6ca27175d00d29d05ca32e396ea1eb5fb01d8256b669cec7663"
 dependencies = [
  "anstream",
  "anstyle",
@@ -800,9 +798,9 @@ dependencies = [
 
 [[package]]
 name = "clap_derive"
-version = "4.3.12"
+version = "4.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "54a9bb5758fc5dfe728d1019941681eccaf0cf8a4189b692a0ee2f2ecf90a050"
+checksum = "cf9804afaaf59a91e75b022a30fb7229a7901f60c755489cc61c9b423b836442"
 dependencies = [
  "heck",
  "proc-macro2",
@@ -812,9 +810,9 @@ dependencies = [
 
 [[package]]
 name = "clap_lex"
-version = "0.5.0"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2da6da31387c7e4ef160ffab6d5e7f00c42626fe39aea70a7b0f1773f7dd6c1b"
+checksum = "702fc72eb24e5a1e48ce58027a675bc24edd52096d5397d4aea7c6dd9eca0bd1"
 
 [[package]]
 name = "cobs"
@@ -1114,10 +1112,11 @@ dependencies = [
 
 [[package]]
 name = "deranged"
-version = "0.3.7"
+version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7684a49fb1af197853ef7b2ee694bc1f5b4179556f1e5710e1760c5db6f5e929"
+checksum = "0f32d04922c60427da6f9fef14d042d9edddef64cb9d4ce0d64d0685fbeb1fd3"
 dependencies = [
+ "powerfmt",
  "serde",
 ]
 
@@ -1276,7 +1275,7 @@ dependencies = [
  "tempfile",
  "thiserror",
  "time",
- "uuid 1.4.1",
+ "uuid 1.5.0",
 ]
 
 [[package]]
@@ -1478,7 +1477,7 @@ dependencies = [
  "faux",
  "tempfile",
  "thiserror",
- "uuid 1.4.1",
+ "uuid 1.5.0",
 ]
 
 [[package]]
@@ -2073,9 +2072,9 @@ dependencies = [
 
 [[package]]
 name = "icu_compactdecimal_data"
-version = "1.3.2"
+version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c2e9b7585f26db531ea5aaedaa68cb66cd2be37fe698b33a289849ff3129545b"
+checksum = "51cc4515902110b79d180c561c13b87e5b42bad85edf719a1d59ec713cd6ccf7"
 
 [[package]]
 name = "icu_datetime"
@@ -2104,9 +2103,9 @@ dependencies = [
 
 [[package]]
 name = "icu_datetime_data"
-version = "1.3.2"
+version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "078b2ed516a2f5054ee7f55b1fe970b92e90ae4cace8a0fe1e5f9fc2e94be609"
+checksum = "ced82224d980ffebafebf443a85c062ac6e801a24415324d0f25962b088f55f4"
 
 [[package]]
 name = "icu_decimal"
@@ -2126,9 +2125,9 @@ dependencies = [
 
 [[package]]
 name = "icu_decimal_data"
-version = "1.3.2"
+version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c064b3828953151f8c610bfff6fec776f958641249ebfd1cf36f073f0654e77"
+checksum = "20116c22b56b74384904ecd5e061fa7ece6e3eb26a48c524fc490ec8f46d26a2"
 
 [[package]]
 name = "icu_displaynames"
@@ -2147,9 +2146,9 @@ dependencies = [
 
 [[package]]
 name = "icu_displaynames_data"
-version = "1.3.2"
+version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "60f9f56c427f1e80383667e8fb13c07707f6561839283115617cc67307a5d020"
+checksum = "220c0ba83e42b255fef61ba9b78f22ba2ce1e27559a4029e3e24092b64f14a06"
 
 [[package]]
 name = "icu_list"
@@ -2273,9 +2272,9 @@ dependencies = [
 
 [[package]]
 name = "icu_properties_data"
-version = "1.3.2"
+version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7c8bb3b67a8347e94d580434369e5c7ee89999b9309d04b7cfc88dfaa0f31b59"
+checksum = "98507b488098f45eb95ef495612a2012e4d8ad6095dda86cb2f1728aa2204a60"
 
 [[package]]
 name = "icu_provider"
@@ -2465,7 +2464,7 @@ dependencies = [
  "tempfile",
  "thiserror",
  "time",
- "uuid 1.4.1",
+ "uuid 1.5.0",
 ]
 
 [[package]]
@@ -3153,7 +3152,7 @@ dependencies = [
  "tokio-stream",
  "toml",
  "urlencoding",
- "uuid 1.4.1",
+ "uuid 1.5.0",
  "vergen",
  "walkdir",
  "yaup",
@@ -3176,7 +3175,7 @@ dependencies = [
  "sha2",
  "thiserror",
  "time",
- "uuid 1.4.1",
+ "uuid 1.5.0",
 ]
 
 [[package]]
@@ -3206,7 +3205,21 @@ dependencies = [
  "thiserror",
  "time",
  "tokio",
- "uuid 1.4.1",
+ "uuid 1.5.0",
+]
+
+[[package]]
+name = "meilitool"
+version = "1.5.0"
+dependencies = [
+ "anyhow",
+ "clap",
+ "dump",
+ "file-store",
+ "meilisearch-auth",
+ "meilisearch-types",
+ "time",
+ "uuid 1.5.0",
 ]
 
 [[package]]
@@ -3286,7 +3299,7 @@ dependencies = [
  "tempfile",
  "thiserror",
  "time",
- "uuid 1.4.1",
+ "uuid 1.5.0",
 ]
 
 [[package]]
@@ -3428,9 +3441,9 @@ dependencies = [
 
 [[package]]
 name = "obkv"
-version = "0.2.0"
+version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f69e48cd7c8e5bb52a1da1287fdbfd877c32673176583ce664cd63b201aba385"
+checksum = "6c459142426056c639ff88d053ebaaaeca0ee1411c94362892398ef4ccd81080"
 
 [[package]]
 name = "once_cell"
@@ -3717,6 +3730,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "powerfmt"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "439ee305def115ba05938db6eb1644ff94165c5ab5e9420d1c1bcedbba909391"
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.17"
@@ -4185,9 +4204,9 @@ checksum = "b0293b4b29daaf487284529cc2f5675b8e57c61f70167ba415a463651fd6a918"
 
 [[package]]
 name = "serde"
-version = "1.0.183"
+version = "1.0.189"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "32ac8da02677876d532745a130fc9d8e6edfa81a269b107c5b00829b91d8eb3c"
+checksum = "8e422a44e74ad4001bdc8eede9a4570ab52f71190e9c076d14369f38b9200537"
 dependencies = [
  "serde_derive",
 ]
@@ -4212,9 +4231,9 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.183"
+version = "1.0.189"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aafe972d60b0b9bee71a91b92fee2d4fb3c9d7e8f6b179aa99f27203d99a4816"
+checksum = "1e48d1f918009ce3145511378cf68d613e3b3d9137d67272562080d68a2b32d5"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4559,12 +4578,13 @@ dependencies = [
 
 [[package]]
 name = "time"
-version = "0.3.25"
+version = "0.3.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b0fdd63d58b18d663fbdf70e049f00a22c8e42be082203be7f26589213cd75ea"
+checksum = "c4a34ab300f2dee6e562c10a046fc05e358b29f9bf92277f30c3c8d82275f6f5"
 dependencies = [
  "deranged",
  "itoa",
+ "powerfmt",
  "serde",
  "time-core",
  "time-macros",
@@ -4572,15 +4592,15 @@ dependencies = [
 
 [[package]]
 name = "time-core"
-version = "0.1.1"
+version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7300fbefb4dadc1af235a9cef3737cea692a9d97e1b9cbcd4ebdae6f8868e6fb"
+checksum = "ef927ca75afb808a4d64dd374f00a2adf8d0fcff8e7b184af886c3c87ec4a3f3"
 
 [[package]]
 name = "time-macros"
-version = "0.2.11"
+version = "0.2.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eb71511c991639bb078fd5bf97757e03914361c48100d52878b8e52b46fb92cd"
+checksum = "4ad70d68dba9e1f8aceda7aa6711965dfec1cac869f311a51bd08b3a2ccbce20"
 dependencies = [
  "time-core",
 ]
@@ -4901,9 +4921,9 @@ dependencies = [
 
 [[package]]
 name = "uuid"
-version = "1.4.1"
+version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "79daa5ed5740825c40b389c5e50312b9c86df53fccd33f281df655642b43869d"
+checksum = "88ad59a7560b41a70d191093a945f0b87bc1deeda46fb237479708a1d6b6cdfc"
 dependencies = [
  "getrandom",
  "serde",

Cargo.toml

@@ -2,6 +2,7 @@
 resolver = "2"
 members = [
     "meilisearch",
+    "meilitool",
     "meilisearch-types",
     "meilisearch-auth",
     "meili-snap",

index-scheduler/src/lib.rs

@@ -27,7 +27,7 @@ mod index_mapper;
 mod insta_snapshot;
 mod lru;
 mod utils;
-mod uuid_codec;
+pub mod uuid_codec;
 
 pub type Result<T> = std::result::Result<T, Error>;
 pub type TaskId = u32;

meilitool/Cargo.toml

@@ -0,0 +1,19 @@
+[package]
+name = "meilitool"
+description = "A CLI to edit a Meilisearch database from the command line"
+version.workspace = true
+authors.workspace = true
+homepage.workspace = true
+readme.workspace = true
+edition.workspace = true
+license.workspace = true
+
+[dependencies]
+anyhow = "1.0.75"
+clap = { version = "4.4.7", features = ["derive"] }
+dump = { path = "../dump" }
+file-store = { path = "../file-store" }
+meilisearch-auth = { path = "../meilisearch-auth" }
+meilisearch-types = { path = "../meilisearch-types" }
+time = { version = "0.3.30", features = ["formatting"] }
+uuid = { version = "1.5.0", features = ["v4"], default-features = false }

meilitool/src/main.rs

@@ -0,0 +1,312 @@
+use std::fs::{read_dir, read_to_string, remove_file, File};
+use std::io::BufWriter;
+use std::path::PathBuf;
+
+use anyhow::Context;
+use clap::{Parser, Subcommand};
+use dump::{DumpWriter, IndexMetadata};
+use file_store::FileStore;
+use meilisearch_auth::AuthController;
+use meilisearch_types::heed::types::{OwnedType, SerdeJson, Str};
+use meilisearch_types::heed::{Database, Env, EnvOpenOptions, PolyDatabase, RoTxn, RwTxn};
+use meilisearch_types::milli::documents::{obkv_to_object, DocumentsBatchReader};
+use meilisearch_types::milli::{obkv_to_json, BEU32};
+use meilisearch_types::tasks::{Status, Task};
+use meilisearch_types::versioning::check_version_file;
+use meilisearch_types::Index;
+use time::macros::format_description;
+use time::OffsetDateTime;
+use uuid_codec::UuidCodec;
+
+mod uuid_codec;
+
+#[derive(Parser)]
+#[command(author, version, about, long_about = None)]
+struct Cli {
+    /// The database path where the Meilisearch is running.
+    #[arg(long, default_value = "data.ms/")]
+    db_path: PathBuf,
+
+    #[command(subcommand)]
+    command: Command,
+}
+
+#[derive(Subcommand)]
+enum Command {
+    /// Clears the task queue and make it empty.
+    ///
+    /// This command can be safely executed even if Meilisearch is running and processing tasks.
+    /// Once the task queue is empty you can restart Meilisearch and no more tasks must be visible,
+    /// even the ones that were processing. However, it's highly possible that you see the processing
+    /// tasks in the queue again with an associated internal error message.
+    ClearTaskQueue,
+
+    /// Exports a dump from the Meilisearch database.
+    ///
+    /// Make sure to run this command when Meilisearch is not running or running but not processing tasks.
+    /// If tasks are being processed while a dump is being exported there are chances for the dump to be
+    /// malformed with missing tasks.
+    ///
+    /// TODO Verify this claim or make sure it cannot happen and we can export dumps
+    ///      without caring about killing Meilisearch first!
+    ExportADump {
+        /// The directory in which the dump will be created.
+        #[arg(long, default_value = "dumps/")]
+        dump_dir: PathBuf,
+
+        /// Skip dumping the enqueued or processing tasks.
+        ///
+        /// Can be useful when there are a lot of them and it is not particularly useful
+        /// to keep them. Note that only the enqueued tasks takes up space so skipping
+        /// the processed ones is not particularly interesting.
+        #[arg(long)]
+        skip_enqueued_tasks: bool,
+    },
+}
+
+fn main() -> anyhow::Result<()> {
+    let Cli { db_path, command } = Cli::parse();
+
+    check_version_file(&db_path).context("While checking the version file")?;
+
+    match command {
+        Command::ClearTaskQueue => clear_task_queue(db_path),
+        Command::ExportADump { dump_dir, skip_enqueued_tasks } => {
+            export_a_dump(db_path, dump_dir, skip_enqueued_tasks)
+        }
+    }
+}
+
+/// Clears the task queue located at `db_path`.
+fn clear_task_queue(db_path: PathBuf) -> anyhow::Result<()> {
+    let path = db_path.join("tasks");
+    let env = EnvOpenOptions::new()
+        .max_dbs(100)
+        .open(&path)
+        .with_context(|| format!("While trying to open {:?}", path.display()))?;
+
+    eprintln!("Deleting tasks from the database...");
+
+    let mut wtxn = env.write_txn()?;
+    let all_tasks = try_opening_poly_database(&env, &wtxn, "all-tasks")?;
+    let total = all_tasks.len(&wtxn)?;
+    let status = try_opening_poly_database(&env, &wtxn, "status")?;
+    let kind = try_opening_poly_database(&env, &wtxn, "kind")?;
+    let index_tasks = try_opening_poly_database(&env, &wtxn, "index-tasks")?;
+    let canceled_by = try_opening_poly_database(&env, &wtxn, "canceled_by")?;
+    let enqueued_at = try_opening_poly_database(&env, &wtxn, "enqueued-at")?;
+    let started_at = try_opening_poly_database(&env, &wtxn, "started-at")?;
+    let finished_at = try_opening_poly_database(&env, &wtxn, "finished-at")?;
+
+    try_clearing_poly_database(&mut wtxn, all_tasks, "all-tasks")?;
+    try_clearing_poly_database(&mut wtxn, status, "status")?;
+    try_clearing_poly_database(&mut wtxn, kind, "kind")?;
+    try_clearing_poly_database(&mut wtxn, index_tasks, "index-tasks")?;
+    try_clearing_poly_database(&mut wtxn, canceled_by, "canceled_by")?;
+    try_clearing_poly_database(&mut wtxn, enqueued_at, "enqueued-at")?;
+    try_clearing_poly_database(&mut wtxn, started_at, "started-at")?;
+    try_clearing_poly_database(&mut wtxn, finished_at, "finished-at")?;
+
+    wtxn.commit().context("While committing the transaction")?;
+
+    eprintln!("Successfully deleted {total} tasks from the tasks database!");
+    eprintln!("Deleting the content files from disk...");
+
+    let mut count = 0usize;
+    let update_files = db_path.join("update_files");
+    let entries = read_dir(&update_files).with_context(|| {
+        format!("While trying to read the content of {:?}", update_files.display())
+    })?;
+    for result in entries {
+        match result {
+            Ok(ent) => match remove_file(ent.path()) {
+                Ok(_) => count += 1,
+                Err(e) => eprintln!("Error while deleting {:?}: {}", ent.path().display(), e),
+            },
+            Err(e) => {
+                eprintln!("Error while reading a file in {:?}: {}", update_files.display(), e)
+            }
+        }
+    }
+
+    eprintln!("Sucessfully deleted {count} content files from disk!");
+
+    Ok(())
+}
+
+fn try_opening_database<KC: 'static, DC: 'static>(
+    env: &Env,
+    rtxn: &RoTxn,
+    db_name: &str,
+) -> anyhow::Result<Database<KC, DC>> {
+    env.open_database(rtxn, Some(db_name))
+        .with_context(|| format!("While opening the {db_name:?} database"))?
+        .with_context(|| format!("Missing the {db_name:?} database"))
+}
+
+fn try_opening_poly_database(
+    env: &Env,
+    rtxn: &RoTxn,
+    db_name: &str,
+) -> anyhow::Result<PolyDatabase> {
+    env.open_poly_database(rtxn, Some(db_name))
+        .with_context(|| format!("While opening the {db_name:?} poly database"))?
+        .with_context(|| format!("Missing the {db_name:?} poly database"))
+}
+
+fn try_clearing_poly_database(
+    wtxn: &mut RwTxn,
+    database: PolyDatabase,
+    db_name: &str,
+) -> anyhow::Result<()> {
+    database.clear(wtxn).with_context(|| format!("While clearing the {db_name:?} database"))
+}
+
+/// Exports a dump into the dump directory.
+fn export_a_dump(
+    db_path: PathBuf,
+    dump_dir: PathBuf,
+    skip_enqueued_tasks: bool,
+) -> Result<(), anyhow::Error> {
+    let started_at = OffsetDateTime::now_utc();
+
+    // 1. Extracts the instance UID from disk
+    let instance_uid_path = db_path.join("instance-uid");
+    let instance_uid = match read_to_string(&instance_uid_path) {
+        Ok(content) => match content.trim().parse() {
+            Ok(uuid) => Some(uuid),
+            Err(e) => {
+                eprintln!("Impossible to parse instance-uid: {e}");
+                None
+            }
+        },
+        Err(e) => {
+            eprintln!("Impossible to read {}: {}", instance_uid_path.display(), e);
+            None
+        }
+    };
+
+    let dump = DumpWriter::new(instance_uid).context("While creating a new dump")?;
+    let file_store =
+        FileStore::new(db_path.join("update_files")).context("While opening the FileStore")?;
+
+    let index_scheduler_path = db_path.join("tasks");
+    let env = EnvOpenOptions::new()
+        .max_dbs(100)
+        .open(&index_scheduler_path)
+        .with_context(|| format!("While trying to open {:?}", index_scheduler_path.display()))?;
+
+    eprintln!("Dumping the keys...");
+
+    // 2. dump the keys
+    let auth_store = AuthController::new(&db_path, &None)
+        .with_context(|| format!("While opening the auth store at {}", db_path.display()))?;
+    let mut dump_keys = dump.create_keys()?;
+    let mut count = 0;
+    for key in auth_store.list_keys()? {
+        dump_keys.push_key(&key)?;
+        count += 1;
+    }
+    dump_keys.flush()?;
+
+    eprintln!("Successfully dumped {count} keys!");
+
+    let rtxn = env.read_txn()?;
+    let all_tasks: Database<OwnedType<BEU32>, SerdeJson<Task>> =
+        try_opening_database(&env, &rtxn, "all-tasks")?;
+    let index_mapping: Database<Str, UuidCodec> =
+        try_opening_database(&env, &rtxn, "index-mapping")?;
+
+    if skip_enqueued_tasks {
+        eprintln!("Skip dumping the enqueued tasks...");
+    } else {
+        eprintln!("Dumping the enqueued tasks...");
+
+        // 3. dump the tasks
+        let mut dump_tasks = dump.create_tasks_queue()?;
+        let mut count = 0;
+        for ret in all_tasks.iter(&rtxn)? {
+            let (_, t) = ret?;
+            let status = t.status;
+            let content_file = t.content_uuid();
+            let mut dump_content_file = dump_tasks.push_task(&t.into())?;
+
+            // 3.1. Dump the `content_file` associated with the task if there is one and the task is not finished yet.
+            if let Some(content_file_uuid) = content_file {
+                if status == Status::Enqueued {
+                    let content_file = file_store.get_update(content_file_uuid)?;
+
+                    let reader =
+                        DocumentsBatchReader::from_reader(content_file).with_context(|| {
+                            format!("While reading content file {:?}", content_file_uuid)
+                        })?;
+
+                    let (mut cursor, documents_batch_index) = reader.into_cursor_and_fields_index();
+                    while let Some(doc) = cursor.next_document().with_context(|| {
+                        format!("While iterating on content file {:?}", content_file_uuid)
+                    })? {
+                        dump_content_file
+                            .push_document(&obkv_to_object(&doc, &documents_batch_index)?)?;
+                    }
+                    dump_content_file.flush()?;
+                    count += 1;
+                }
+            }
+        }
+        dump_tasks.flush()?;
+
+        eprintln!("Successfully dumped {count} enqueued tasks!");
+    }
+
+    eprintln!("Dumping the indexes...");
+
+    // 4. Dump the indexes
+    let mut count = 0;
+    for result in index_mapping.iter(&rtxn)? {
+        let (uid, uuid) = result?;
+        let index_path = db_path.join("indexes").join(uuid.to_string());
+        let index = Index::new(EnvOpenOptions::new(), &index_path).with_context(|| {
+            format!("While trying to open the index at path {:?}", index_path.display())
+        })?;
+
+        let rtxn = index.read_txn()?;
+        let metadata = IndexMetadata {
+            uid: uid.to_owned(),
+            primary_key: index.primary_key(&rtxn)?.map(String::from),
+            created_at: index.created_at(&rtxn)?,
+            updated_at: index.updated_at(&rtxn)?,
+        };
+        let mut index_dumper = dump.create_index(uid, &metadata)?;
+
+        let fields_ids_map = index.fields_ids_map(&rtxn)?;
+        let all_fields: Vec<_> = fields_ids_map.iter().map(|(id, _)| id).collect();
+
+        // 4.1. Dump the documents
+        for ret in index.all_documents(&rtxn)? {
+            let (_id, doc) = ret?;
+            let document = obkv_to_json(&all_fields, &fields_ids_map, doc)?;
+            index_dumper.push_document(&document)?;
+        }
+
+        // 4.2. Dump the settings
+        let settings = meilisearch_types::settings::settings(&index, &rtxn)?;
+        index_dumper.settings(&settings)?;
+        count += 1;
+    }
+
+    eprintln!("Successfully dumped {count} indexes!");
+    // We will not dump experimental feature settings
+    eprintln!("The tool is not dumping experimental features, please set them by hand afterward");
+
+    let dump_uid = started_at.format(format_description!(
+        "[year repr:full][month repr:numerical][day padding:zero]-[hour padding:zero][minute padding:zero][second padding:zero][subsecond digits:3]"
+    )).unwrap();
+
+    let path = dump_dir.join(format!("{}.dump", dump_uid));
+    let file = File::create(&path)?;
+    dump.persist_to(BufWriter::new(file))?;
+
+    eprintln!("Dump exported at path {:?}", path.display());
+
+    Ok(())
+}

meilitool/src/uuid_codec.rs

@@ -0,0 +1,24 @@
+use std::borrow::Cow;
+use std::convert::TryInto;
+
+use meilisearch_types::heed::{BytesDecode, BytesEncode};
+use uuid::Uuid;
+
+/// A heed codec for value of struct Uuid.
+pub struct UuidCodec;
+
+impl<'a> BytesDecode<'a> for UuidCodec {
+    type DItem = Uuid;
+
+    fn bytes_decode(bytes: &'a [u8]) -> Option<Self::DItem> {
+        bytes.try_into().ok().map(Uuid::from_bytes)
+    }
+}
+
+impl BytesEncode<'_> for UuidCodec {
+    type EItem = Uuid;
+
+    fn bytes_encode(item: &Self::EItem) -> Option<Cow<[u8]>> {
+        Some(Cow::Borrowed(item.as_bytes()))
+    }
+}