From fd5c48941a8c8a9ad0d31270a54be2f90440efb2 Mon Sep 17 00:00:00 2001
From: Tamo <tamo@meilisearch.com>
Date: Thu, 23 Feb 2023 19:31:57 +0100
Subject: [PATCH 1/6] Add cache on the indexes stats

---
 index-scheduler/src/batch.rs            | 38 +++++++++++++++++++--
 index-scheduler/src/index_mapper/mod.rs | 42 +++++++++++++++++++++--
 index-scheduler/src/lib.rs              | 19 +++++++++--
 meilisearch/src/routes/indexes/mod.rs   | 45 +++++++++++--------------
 meilisearch/src/routes/mod.rs           | 38 +++++++--------------
 5 files changed, 122 insertions(+), 60 deletions(-)

diff --git a/index-scheduler/src/batch.rs b/index-scheduler/src/batch.rs
index 66c516d9b..03287d7ae 100644
--- a/index-scheduler/src/batch.rs
+++ b/index-scheduler/src/batch.rs
@@ -828,20 +828,36 @@ impl IndexScheduler {
                 Ok(vec![task])
             }
             Batch::IndexOperation { op, must_create_index } => {
-                let index_uid = op.index_uid();
+                let index_uid = op.index_uid().to_string();
                 let index = if must_create_index {
                     // create the index if it doesn't already exist
                     let wtxn = self.env.write_txn()?;
-                    self.index_mapper.create_index(wtxn, index_uid, None)?
+                    self.index_mapper.create_index(wtxn, &index_uid, None)?
                 } else {
                     let rtxn = self.env.read_txn()?;
-                    self.index_mapper.index(&rtxn, index_uid)?
+                    self.index_mapper.index(&rtxn, &index_uid)?
                 };
 
                 let mut index_wtxn = index.write_txn()?;
                 let tasks = self.apply_index_operation(&mut index_wtxn, &index, op)?;
                 index_wtxn.commit()?;
 
+                // if the update processed successfully, we're going to store the new
+                // stats of the index. Since the tasks have already been processed and
+                // this is a non-critical operation. If it fails, we should not fail
+                // the entire batch.
+                let res = || -> Result<()> {
+                    let mut wtxn = self.env.write_txn()?;
+                    self.index_mapper.compute_and_store_stats_of(&mut wtxn, &index_uid)?;
+                    wtxn.commit()?;
+                    Ok(())
+                }();
+
+                match res {
+                    Ok(_) => (),
+                    Err(e) => error!("Could not write the stats of the index {}", e),
+                }
+
                 Ok(tasks)
             }
             Batch::IndexCreation { index_uid, primary_key, task } => {
@@ -875,6 +891,22 @@ impl IndexScheduler {
                 task.status = Status::Succeeded;
                 task.details = Some(Details::IndexInfo { primary_key });
 
+                // if the update processed successfully, we're going to store the new
+                // stats of the index. Since the tasks have already been processed and
+                // this is a non-critical operation. If it fails, we should not fail
+                // the entire batch.
+                let res = || -> Result<()> {
+                    let mut wtxn = self.env.write_txn()?;
+                    self.index_mapper.compute_and_store_stats_of(&mut wtxn, &index_uid)?;
+                    wtxn.commit()?;
+                    Ok(())
+                }();
+
+                match res {
+                    Ok(_) => (),
+                    Err(e) => error!("Could not write the stats of the index {}", e),
+                }
+
                 Ok(vec![task])
             }
             Batch::IndexDeletion { index_uid, index_has_been_created, mut tasks } => {
diff --git a/index-scheduler/src/index_mapper/mod.rs b/index-scheduler/src/index_mapper/mod.rs
index 1693d12d7..9e1de438a 100644
--- a/index-scheduler/src/index_mapper/mod.rs
+++ b/index-scheduler/src/index_mapper/mod.rs
@@ -4,10 +4,11 @@ use std::time::Duration;
 use std::{fs, thread};
 
 use log::error;
-use meilisearch_types::heed::types::Str;
+use meilisearch_types::heed::types::{SerdeJson, Str};
 use meilisearch_types::heed::{Database, Env, RoTxn, RwTxn};
 use meilisearch_types::milli::update::IndexerConfig;
-use meilisearch_types::milli::Index;
+use meilisearch_types::milli::{FieldDistribution, Index};
+use serde::{Deserialize, Serialize};
 use time::OffsetDateTime;
 use uuid::Uuid;
 
@@ -19,6 +20,7 @@ use crate::{Error, Result};
 mod index_map;
 
 const INDEX_MAPPING: &str = "index-mapping";
+const INDEX_STATS: &str = "index-stats";
 
 /// Structure managing meilisearch's indexes.
 ///
@@ -52,6 +54,8 @@ pub struct IndexMapper {
 
     /// Map an index name with an index uuid currently available on disk.
     pub(crate) index_mapping: Database<Str, UuidCodec>,
+    /// Map an index name with the cached stats associated to the index.
+    pub(crate) index_stats: Database<Str, SerdeJson<IndexStats>>,
 
     /// Path to the folder where the LMDB environments of each index are.
     base_path: PathBuf,
@@ -76,6 +80,15 @@ pub enum IndexStatus {
     Available(Index),
 }
 
+#[derive(Serialize, Deserialize, Debug)]
+pub struct IndexStats {
+    pub number_of_documents: u64,
+    pub database_size: u64,
+    pub field_distribution: FieldDistribution,
+    pub created_at: OffsetDateTime,
+    pub updated_at: OffsetDateTime,
+}
+
 impl IndexMapper {
     pub fn new(
         env: &Env,
@@ -88,6 +101,7 @@ impl IndexMapper {
         Ok(Self {
             index_map: Arc::new(RwLock::new(IndexMap::new(index_count))),
             index_mapping: env.create_database(Some(INDEX_MAPPING))?,
+            index_stats: env.create_database(Some(INDEX_STATS))?,
             base_path,
             index_base_map_size,
             index_growth_amount,
@@ -135,6 +149,7 @@ impl IndexMapper {
     /// 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<()> {
+        self.index_stats.delete(&mut wtxn, name)?;
         let uuid = self
             .index_mapping
             .get(&wtxn, name)?
@@ -360,6 +375,29 @@ impl IndexMapper {
         Ok(())
     }
 
+    /// Return the stored stats of an index.
+    pub fn stats_of(&self, rtxn: &RoTxn, index_uid: &str) -> Result<IndexStats> {
+        self.index_stats
+            .get(rtxn, index_uid)?
+            .ok_or_else(|| Error::IndexNotFound(index_uid.to_string()))
+    }
+
+    /// Return the stats of an index and write it in the index-mapper database.
+    pub fn compute_and_store_stats_of(&self, wtxn: &mut RwTxn, index_uid: &str) -> Result<()> {
+        let index = self.index(wtxn, index_uid)?;
+        let database_size = index.on_disk_size()?;
+        let rtxn = index.read_txn()?;
+        let stats = IndexStats {
+            number_of_documents: index.number_of_documents(&rtxn)?,
+            database_size,
+            field_distribution: index.field_distribution(&rtxn)?,
+            created_at: index.created_at(&rtxn)?,
+            updated_at: index.updated_at(&rtxn)?,
+        };
+        self.index_stats.put(wtxn, index_uid, &stats)?;
+        Ok(())
+    }
+
     pub fn index_exists(&self, rtxn: &RoTxn, name: &str) -> Result<bool> {
         Ok(self.index_mapping.get(rtxn, name)?.is_some())
     }
diff --git a/index-scheduler/src/lib.rs b/index-scheduler/src/lib.rs
index e23e4ff8b..4f875eaca 100644
--- a/index-scheduler/src/lib.rs
+++ b/index-scheduler/src/lib.rs
@@ -44,10 +44,9 @@ use file_store::FileStore;
 use meilisearch_types::error::ResponseError;
 use meilisearch_types::heed::types::{OwnedType, SerdeBincode, SerdeJson, Str};
 use meilisearch_types::heed::{self, Database, Env, RoTxn};
-use meilisearch_types::milli;
 use meilisearch_types::milli::documents::DocumentsBatchBuilder;
 use meilisearch_types::milli::update::IndexerConfig;
-use meilisearch_types::milli::{CboRoaringBitmapCodec, Index, RoaringBitmapCodec, BEU32};
+use meilisearch_types::milli::{self, CboRoaringBitmapCodec, Index, RoaringBitmapCodec, BEU32};
 use meilisearch_types::tasks::{Kind, KindWithContent, Status, Task};
 use roaring::RoaringBitmap;
 use synchronoise::SignalEvent;
@@ -566,7 +565,7 @@ impl IndexScheduler {
     }
 
     /// Return the name of all indexes without opening them.
-    pub fn index_names(self) -> Result<Vec<String>> {
+    pub fn index_names(&self) -> Result<Vec<String>> {
         let rtxn = self.env.read_txn()?;
         self.index_mapper.index_names(&rtxn)
     }
@@ -1186,6 +1185,14 @@ impl IndexScheduler {
         Ok(TickOutcome::TickAgain(processed_tasks))
     }
 
+    pub fn index_stats(&self, index_uid: &str) -> Result<IndexStats> {
+        let is_indexing = self.is_index_processing(index_uid)?;
+        let rtxn = self.read_txn()?;
+        let index_stats = self.index_mapper.stats_of(&rtxn, index_uid)?;
+
+        Ok(IndexStats { is_indexing, inner_stats: index_stats })
+    }
+
     pub(crate) fn delete_persisted_task_data(&self, task: &Task) -> Result<()> {
         match task.content_uuid() {
             Some(content_file) => self.delete_update_file(content_file),
@@ -1238,6 +1245,12 @@ struct IndexBudget {
     task_db_size: usize,
 }
 
+#[derive(Debug)]
+pub struct IndexStats {
+    pub is_indexing: bool,
+    pub inner_stats: index_mapper::IndexStats,
+}
+
 #[cfg(test)]
 mod tests {
     use std::io::{BufWriter, Seek, Write};
diff --git a/meilisearch/src/routes/indexes/mod.rs b/meilisearch/src/routes/indexes/mod.rs
index c5c168786..28988e30b 100644
--- a/meilisearch/src/routes/indexes/mod.rs
+++ b/meilisearch/src/routes/indexes/mod.rs
@@ -220,6 +220,24 @@ pub async fn delete_index(
     Ok(HttpResponse::Accepted().json(task))
 }
 
+#[derive(Serialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct IndexStats {
+    pub number_of_documents: u64,
+    pub is_indexing: bool,
+    pub field_distribution: FieldDistribution,
+}
+
+impl From<index_scheduler::IndexStats> for IndexStats {
+    fn from(stats: index_scheduler::IndexStats) -> Self {
+        IndexStats {
+            number_of_documents: stats.inner_stats.number_of_documents,
+            is_indexing: stats.is_indexing,
+            field_distribution: stats.inner_stats.field_distribution,
+        }
+    }
+}
+
 pub async fn get_index_stats(
     index_scheduler: GuardedData<ActionPolicy<{ actions::STATS_GET }>, Data<IndexScheduler>>,
     index_uid: web::Path<String>,
@@ -229,33 +247,8 @@ pub async fn get_index_stats(
     let index_uid = IndexUid::try_from(index_uid.into_inner())?;
     analytics.publish("Stats Seen".to_string(), json!({ "per_index_uid": true }), Some(&req));
 
-    let stats = IndexStats::new((*index_scheduler).clone(), index_uid.into_inner())?;
+    let stats = IndexStats::from(index_scheduler.index_stats(&index_uid)?);
 
     debug!("returns: {:?}", stats);
     Ok(HttpResponse::Ok().json(stats))
 }
-
-#[derive(Serialize, Debug)]
-#[serde(rename_all = "camelCase")]
-pub struct IndexStats {
-    pub number_of_documents: u64,
-    pub is_indexing: bool,
-    pub field_distribution: FieldDistribution,
-}
-
-impl IndexStats {
-    pub fn new(
-        index_scheduler: Data<IndexScheduler>,
-        index_uid: String,
-    ) -> Result<Self, ResponseError> {
-        // we check if there is currently a task processing associated with this index.
-        let is_processing = index_scheduler.is_index_processing(&index_uid)?;
-        let index = index_scheduler.index(&index_uid)?;
-        let rtxn = index.read_txn()?;
-        Ok(IndexStats {
-            number_of_documents: index.number_of_documents(&rtxn)?,
-            is_indexing: is_processing,
-            field_distribution: index.field_distribution(&rtxn)?,
-        })
-    }
-}
diff --git a/meilisearch/src/routes/mod.rs b/meilisearch/src/routes/mod.rs
index a4523e53f..f54c8ee38 100644
--- a/meilisearch/src/routes/mod.rs
+++ b/meilisearch/src/routes/mod.rs
@@ -2,7 +2,7 @@ use std::collections::BTreeMap;
 
 use actix_web::web::Data;
 use actix_web::{web, HttpRequest, HttpResponse};
-use index_scheduler::{IndexScheduler, Query};
+use index_scheduler::IndexScheduler;
 use log::debug;
 use meilisearch_auth::AuthController;
 use meilisearch_types::error::ResponseError;
@@ -12,7 +12,6 @@ use serde::{Deserialize, Serialize};
 use serde_json::json;
 use time::OffsetDateTime;
 
-use self::indexes::IndexStats;
 use crate::analytics::Analytics;
 use crate::extractors::authentication::policies::*;
 use crate::extractors::authentication::GuardedData;
@@ -234,7 +233,7 @@ pub struct Stats {
     pub database_size: u64,
     #[serde(serialize_with = "time::serde::rfc3339::option::serialize")]
     pub last_update: Option<OffsetDateTime>,
-    pub indexes: BTreeMap<String, IndexStats>,
+    pub indexes: BTreeMap<String, indexes::IndexStats>,
 }
 
 async fn get_stats(
@@ -260,32 +259,19 @@ pub fn create_all_stats(
     let mut last_task: Option<OffsetDateTime> = None;
     let mut indexes = BTreeMap::new();
     let mut database_size = 0;
-    let processing_task = index_scheduler.get_tasks_from_authorized_indexes(
-        Query { statuses: Some(vec![Status::Processing]), limit: Some(1), ..Query::default() },
-        filters,
-    )?;
+
     // accumulate the size of each indexes
-    let processing_index = processing_task.first().and_then(|task| task.index_uid());
-    index_scheduler.try_for_each_index(|name, index| {
-        if !filters.is_index_authorized(name) {
-            return Ok(());
+    for index_uid in index_scheduler.index_names()? {
+        if !filters.is_index_authorized(&index_uid) {
+            continue;
         }
 
-        database_size += index.on_disk_size()?;
-
-        let rtxn = index.read_txn()?;
-        let stats = IndexStats {
-            number_of_documents: index.number_of_documents(&rtxn)?,
-            is_indexing: processing_index.map_or(false, |index_name| name == index_name),
-            field_distribution: index.field_distribution(&rtxn)?,
-        };
-
-        let updated_at = index.updated_at(&rtxn)?;
-        last_task = last_task.map_or(Some(updated_at), |last| Some(last.max(updated_at)));
-
-        indexes.insert(name.to_string(), stats);
-        Ok(())
-    })?;
+        let stats = index_scheduler.index_stats(&index_uid)?;
+        last_task = last_task.map_or(Some(stats.inner_stats.updated_at), |last| {
+            Some(last.max(stats.inner_stats.updated_at))
+        });
+        indexes.insert(index_uid.to_string(), stats.into());
+    }
 
     database_size += index_scheduler.size()?;
     database_size += auth_controller.size()?;

From 3bbf7605427e3b644b367a72ea9e592ff661b29d Mon Sep 17 00:00:00 2001
From: Tamo <tamo@meilisearch.com>
Date: Thu, 23 Feb 2023 19:53:58 +0100
Subject: [PATCH 2/6] update most snapshots

---
 index-scheduler/src/insta_snapshot.rs                | 12 +++++++++++-
 .../cancel_enqueued_task/cancel_processed.snap       |  3 +--
 .../cancel_enqueued_task/initial_tasks_enqueued.snap |  2 +-
 .../cancel_mix_of_tasks/first_task_processed.snap    |  3 ++-
 .../processing_second_task_cancel_enqueued.snap      |  3 ++-
 .../cancel_task_registered.snap                      |  2 +-
 .../initial_task_processing.snap                     |  2 +-
 .../registered_the_first_task.snap                   |  2 +-
 .../cancel_succeeded_task/cancel_processed.snap      |  3 ++-
 .../initial_task_processed.snap                      |  3 ++-
 .../registered_the_first_task.snap                   |  2 +-
 .../all_tasks_processed.snap                         |  5 ++++-
 .../lib.rs/document_addition/after_register.snap     |  2 +-
 .../document_addition/after_the_batch_creation.snap  |  2 +-
 .../once_everything_is_processed.snap                |  3 ++-
 .../after_processing_the_batch.snap                  |  3 ++-
 .../registered_the_first_task.snap                   |  2 +-
 .../registered_the_second_task.snap                  |  2 +-
 .../before_index_creation.snap                       |  3 ++-
 .../both_task_succeeded.snap                         |  2 +-
 .../registered_the_first_task.snap                   |  2 +-
 .../registered_the_second_task.snap                  |  2 +-
 .../registered_the_third_task.snap                   |  2 +-
 .../1.snap                                           |  2 +-
 .../2.snap                                           |  2 +-
 .../after_failing_the_deletion.snap                  |  2 +-
 .../after_last_successful_addition.snap              |  3 ++-
 .../registered_the_first_task.snap                   |  2 +-
 .../registered_the_second_task.snap                  |  2 +-
 .../document_addition_batch_created.snap             |  2 +-
 .../document_addition_failed.snap                    |  2 +-
 .../registered_the_first_task.snap                   |  2 +-
 .../after_register.snap                              |  2 +-
 .../index_creation_failed.snap                       |  2 +-
 .../after_batch_succeeded.snap                       |  3 ++-
 .../after_failing_to_commit.snap                     |  3 ++-
 ...on_succeeded_but_index_scheduler_not_updated.snap |  2 +-
 .../registered_the_first_task.snap                   |  2 +-
 .../task_successfully_processed.snap                 |  3 ++-
 .../after_batch_creation.snap                        |  2 +-
 .../registered_the_first_task.snap                   |  2 +-
 .../registered_the_second_task.snap                  |  2 +-
 .../registered_the_third_task.snap                   |  2 +-
 .../index_creation_failed.snap                       |  2 +-
 .../registered_the_first_task.snap                   |  2 +-
 .../processed_the_first_task.snap                    |  3 ++-
 .../processed_the_second_task.snap                   |  4 +++-
 .../processed_the_third_task.snap                    |  3 ++-
 .../registered_the_first_task.snap                   |  2 +-
 .../registered_the_second_task.snap                  |  2 +-
 .../registered_the_third_task.snap                   |  2 +-
 .../process_tasks_without_autobatching/first.snap    |  3 ++-
 .../process_tasks_without_autobatching/fourth.snap   |  3 ++-
 .../registered_the_first_task.snap                   |  2 +-
 .../registered_the_fourth_task.snap                  |  2 +-
 .../registered_the_second_task.snap                  |  2 +-
 .../registered_the_third_task.snap                   |  2 +-
 .../process_tasks_without_autobatching/second.snap   |  3 ++-
 .../process_tasks_without_autobatching/third.snap    |  3 ++-
 .../lib.rs/query_tasks_canceled_by/start.snap        |  3 ++-
 .../processed_all_tasks.snap                         |  5 ++++-
 .../registered_the_first_task.snap                   |  2 +-
 .../registered_the_second_task.snap                  |  2 +-
 .../registered_the_third_task.snap                   |  2 +-
 .../src/snapshots/lib.rs/query_tasks_simple/end.snap |  4 +++-
 .../snapshots/lib.rs/query_tasks_simple/start.snap   |  2 +-
 .../lib.rs/query_tasks_special_rules/start.snap      |  2 +-
 .../everything_is_succesfully_registered.snap        |  2 +-
 .../src/snapshots/lib.rs/swap_indexes/create_a.snap  |  3 ++-
 .../src/snapshots/lib.rs/swap_indexes/create_b.snap  |  4 +++-
 .../src/snapshots/lib.rs/swap_indexes/create_c.snap  |  5 ++++-
 .../src/snapshots/lib.rs/swap_indexes/create_d.snap  |  6 +++++-
 .../lib.rs/swap_indexes/first_swap_processed.snap    |  6 +++++-
 .../lib.rs/swap_indexes/first_swap_registered.snap   |  6 +++++-
 .../lib.rs/swap_indexes/second_swap_processed.snap   |  6 +++++-
 .../swap_indexes/third_empty_swap_processed.snap     |  6 +++++-
 .../lib.rs/swap_indexes/two_swaps_registered.snap    |  6 +++++-
 .../after_the_index_creation.snap                    |  6 +++++-
 .../swap_indexes_errors/first_swap_failed.snap       |  6 +++++-
 .../swap_indexes_errors/initial_tasks_processed.snap |  6 +++++-
 .../initial_tasks_enqueued.snap                      |  2 +-
 .../initial_tasks_processed.snap                     |  3 ++-
 .../task_deletion_processed.snap                     |  3 ++-
 .../after_registering_the_task_deletion.snap         |  3 ++-
 .../initial_tasks_enqueued.snap                      |  2 +-
 .../initial_tasks_processed.snap                     |  3 ++-
 .../task_deletion_processed.snap                     |  3 ++-
 .../initial_tasks_enqueued.snap                      |  2 +-
 .../task_deletion_done.snap                          |  2 +-
 .../task_deletion_enqueued.snap                      |  2 +-
 .../task_deletion_processing.snap                    |  2 +-
 .../after_processing_the_10_tasks.snap               |  3 ++-
 .../after_registering_the_10_tasks.snap              |  3 ++-
 .../processed_the_first_task.snap                    |  3 ++-
 .../registered_the_first_task.snap                   |  2 +-
 .../after_registering_the_10_tasks.snap              |  3 ++-
 .../all_tasks_processed.snap                         |  3 ++-
 .../five_tasks_processed.snap                        |  3 ++-
 .../processed_the_first_task.snap                    |  3 ++-
 .../registered_the_first_task.snap                   |  2 +-
 .../after_processing_the_10_tasks.snap               |  2 +-
 .../after_registering_the_10_tasks.snap              |  2 +-
 .../after_registering_the_10_tasks.snap              |  2 +-
 .../all_tasks_processed.snap                         |  2 +-
 .../five_tasks_processed.snap                        |  2 +-
 .../after_registering_the_10_tasks.snap              |  2 +-
 .../all_tasks_processed.snap                         |  3 ++-
 .../only_first_task_failed.snap                      |  2 +-
 .../after_registering_the_10_tasks.snap              |  3 ++-
 .../all_tasks_processed.snap                         |  3 ++-
 .../processed_the_first_task.snap                    |  3 ++-
 .../registered_the_first_task.snap                   |  2 +-
 .../after_registering_the_5_tasks.snap               |  2 +-
 .../fifth_task_succeeds.snap                         |  3 ++-
 .../first_and_second_task_fails.snap                 |  3 ++-
 .../fourth_task_fails.snap                           |  3 ++-
 .../third_task_succeeds.snap                         |  3 ++-
 .../after_registering_the_3_tasks.snap               |  2 +-
 .../only_first_task_succeed.snap                     |  3 ++-
 .../second_task_fails.snap                           |  3 ++-
 .../third_task_fails.snap                            |  3 ++-
 .../after_registering_the_3_tasks.snap               |  2 +-
 .../only_first_task_succeed.snap                     |  3 ++-
 .../second_and_third_tasks_fails.snap                |  3 ++-
 .../after_registering_the_6_tasks.snap               |  2 +-
 .../all_other_tasks_succeeds.snap                    |  3 ++-
 .../first_task_fails.snap                            |  3 ++-
 .../second_task_fails.snap                           |  3 ++-
 .../third_task_succeeds.snap                         |  3 ++-
 .../after_registering_the_6_tasks.snap               |  2 +-
 .../all_other_tasks_succeeds.snap                    |  3 ++-
 .../first_task_succeed.snap                          |  3 ++-
 .../second_task_fails.snap                           |  3 ++-
 .../third_task_succeeds.snap                         |  3 ++-
 .../snapshots/lib.rs/test_document_replace/1.snap    |  2 +-
 .../snapshots/lib.rs/test_document_replace/2.snap    |  3 ++-
 .../after_registering_the_10_tasks.snap              |  2 +-
 .../all_tasks_processed.snap                         |  3 ++-
 .../five_tasks_processed.snap                        |  3 ++-
 .../src/snapshots/lib.rs/test_document_update/1.snap |  2 +-
 .../src/snapshots/lib.rs/test_document_update/2.snap |  3 ++-
 .../after_registering_the_10_tasks.snap              |  2 +-
 .../all_tasks_processed.snap                         |  3 ++-
 .../five_tasks_processed.snap                        |  3 ++-
 .../after_registering_the_10_tasks.snap              |  2 +-
 .../all_tasks_processed.snap                         |  3 ++-
 .../five_tasks_processed.snap                        |  3 ++-
 147 files changed, 268 insertions(+), 148 deletions(-)

diff --git a/index-scheduler/src/insta_snapshot.rs b/index-scheduler/src/insta_snapshot.rs
index dcc348c98..43509aa84 100644
--- a/index-scheduler/src/insta_snapshot.rs
+++ b/index-scheduler/src/insta_snapshot.rs
@@ -254,6 +254,16 @@ pub fn snapshot_canceled_by(
     snap
 }
 pub fn snapshot_index_mapper(rtxn: &RoTxn, mapper: &IndexMapper) -> String {
+    let mut s = String::new();
     let names = mapper.index_names(rtxn).unwrap();
-    format!("{names:?}")
+
+    for name in names {
+        let stats = mapper.stats_of(rtxn, &name).unwrap();
+        s.push_str(&format!(
+            "{name}: {{ number_of_documents: {}, field_distribution: {:?} }}\n",
+            stats.number_of_documents, stats.field_distribution
+        ));
+    }
+
+    s
 }
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/cancel_processed.snap b/index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/cancel_processed.snap
index a06b82c74..077784965 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/cancel_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/cancel_processed.snap
@@ -1,6 +1,5 @@
 ---
 source: index-scheduler/src/lib.rs
-assertion_line: 1755
 ---
 ### Autobatching Enabled = true
 ### Processing Tasks:
@@ -23,7 +22,7 @@ canceled [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 1 [0,]
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/initial_tasks_enqueued.snap b/index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/initial_tasks_enqueued.snap
index 743e74a14..3d3830b29 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/initial_tasks_enqueued.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_enqueued_task/initial_tasks_enqueued.snap
@@ -20,7 +20,7 @@ enqueued [0,1,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/first_task_processed.snap b/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/first_task_processed.snap
index 36d34ff93..16be0e4d5 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/first_task_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/first_task_processed.snap
@@ -23,7 +23,8 @@ catto [0,]
 wolfo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/processing_second_task_cancel_enqueued.snap b/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/processing_second_task_cancel_enqueued.snap
index 30da295f9..46ccfcb8b 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/processing_second_task_cancel_enqueued.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/processing_second_task_cancel_enqueued.snap
@@ -25,7 +25,8 @@ catto [0,]
 wolfo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_task_registered.snap b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_task_registered.snap
index 061f334c8..f65b5ee67 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_task_registered.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_task_registered.snap
@@ -20,7 +20,7 @@ enqueued [0,1,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/initial_task_processing.snap b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/initial_task_processing.snap
index 905cec451..8a3ad4661 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/initial_task_processing.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/initial_task_processing.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/registered_the_first_task.snap
index d454b501e..6873f8b56 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/cancel_processed.snap b/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/cancel_processed.snap
index b3842cc12..36e47f569 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/cancel_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/cancel_processed.snap
@@ -21,7 +21,8 @@ succeeded [0,1,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 1 []
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/initial_task_processed.snap b/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/initial_task_processed.snap
index e52a80fae..028e03446 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/initial_task_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/initial_task_processed.snap
@@ -19,7 +19,8 @@ succeeded [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/registered_the_first_task.snap
index d454b501e..6873f8b56 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_succeeded_task/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/do_not_batch_task_of_different_indexes/all_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/do_not_batch_task_of_different_indexes/all_tasks_processed.snap
index f9195857a..c9a12c327 100644
--- a/index-scheduler/src/snapshots/lib.rs/do_not_batch_task_of_different_indexes/all_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/do_not_batch_task_of_different_indexes/all_tasks_processed.snap
@@ -27,7 +27,10 @@ doggos [0,3,]
 girafos [2,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["cattos", "doggos", "girafos"]
+cattos: { number_of_documents: 0, field_distribution: {} }
+doggos: { number_of_documents: 0, field_distribution: {} }
+girafos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition/after_register.snap b/index-scheduler/src/snapshots/lib.rs/document_addition/after_register.snap
index 3e654a0e2..c1869a475 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition/after_register.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition/after_register.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition/after_the_batch_creation.snap b/index-scheduler/src/snapshots/lib.rs/document_addition/after_the_batch_creation.snap
index 10291b206..33d58eab6 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition/after_the_batch_creation.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition/after_the_batch_creation.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition/once_everything_is_processed.snap b/index-scheduler/src/snapshots/lib.rs/document_addition/once_everything_is_processed.snap
index 6079a4317..b4a6da3af 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition/once_everything_is_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition/once_everything_is_processed.snap
@@ -19,7 +19,8 @@ succeeded [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/after_processing_the_batch.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/after_processing_the_batch.snap
index f70496b81..b27288a0f 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/after_processing_the_batch.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/after_processing_the_batch.snap
@@ -21,7 +21,8 @@ succeeded [0,1,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/registered_the_first_task.snap
index 35dc0b41a..d26e62bff 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/registered_the_second_task.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/registered_the_second_task.snap
index bd65a6d99..e0f371120 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/registered_the_second_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_document_deletion/registered_the_second_task.snap
@@ -20,7 +20,7 @@ enqueued [0,1,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/before_index_creation.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/before_index_creation.snap
index 379e90120..97ba419a8 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/before_index_creation.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/before_index_creation.snap
@@ -23,7 +23,8 @@ succeeded [0,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/both_task_succeeded.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/both_task_succeeded.snap
index 2ff82bfd2..fd96ee974 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/both_task_succeeded.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/both_task_succeeded.snap
@@ -23,7 +23,7 @@ succeeded [0,1,2,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_first_task.snap
index e23cd648f..1a29c1ac6 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_second_task.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_second_task.snap
index 86674ccd0..68ded1f0d 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_second_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_second_task.snap
@@ -20,7 +20,7 @@ enqueued [0,1,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_third_task.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_third_task.snap
index f4d3a8190..1601a6b25 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_third_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion/registered_the_third_task.snap
@@ -22,7 +22,7 @@ enqueued [0,1,2,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/1.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/1.snap
index e0813f109..c200ce402 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/1.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/1.snap
@@ -20,7 +20,7 @@ enqueued [0,1,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/2.snap b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/2.snap
index f8586b7b8..7884dfe08 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/2.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_addition_and_index_deletion_on_unexisting_index/2.snap
@@ -21,7 +21,7 @@ succeeded [0,1,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/after_failing_the_deletion.snap b/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/after_failing_the_deletion.snap
index 2850af744..1d4aa24e2 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/after_failing_the_deletion.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/after_failing_the_deletion.snap
@@ -21,7 +21,7 @@ failed [0,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/after_last_successful_addition.snap b/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/after_last_successful_addition.snap
index 59e18bdb0..0f9dfd3e6 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/after_last_successful_addition.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/after_last_successful_addition.snap
@@ -22,7 +22,8 @@ failed [0,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 3, field_distribution: {"catto": 1, "doggo": 2, "id": 3} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/registered_the_first_task.snap
index 9356e6dba..5753db7e6 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/registered_the_second_task.snap b/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/registered_the_second_task.snap
index 89e341184..0b6191f9e 100644
--- a/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/registered_the_second_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/document_deletion_and_document_addition/registered_the_second_task.snap
@@ -20,7 +20,7 @@ enqueued [0,1,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_batch_created.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_batch_created.snap
index 10291b206..33d58eab6 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_batch_created.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_batch_created.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_failed.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_failed.snap
index c1bfd7db9..18edc3613 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_failed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/document_addition_failed.snap
@@ -19,7 +19,7 @@ failed [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/registered_the_first_task.snap
index 3e654a0e2..c1869a475 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_document_addition/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/after_register.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/after_register.snap
index 63a2d606e..f252cc8ef 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/after_register.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/after_register.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/index_creation_failed.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/index_creation_failed.snap
index 252ae082e..d2b06a4f4 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/index_creation_failed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_process_batch_for_index_creation/index_creation_failed.snap
@@ -19,7 +19,7 @@ failed [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/after_batch_succeeded.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/after_batch_succeeded.snap
index bdda4e086..9c31fd318 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/after_batch_succeeded.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/after_batch_succeeded.snap
@@ -18,7 +18,8 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/after_failing_to_commit.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/after_failing_to_commit.snap
index bdda4e086..9c31fd318 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/after_failing_to_commit.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/after_failing_to_commit.snap
@@ -18,7 +18,8 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/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 b/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
index 3e654a0e2..c1869a475 100644
--- a/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
+++ b/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
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/registered_the_first_task.snap
index 3e654a0e2..c1869a475 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/task_successfully_processed.snap b/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/task_successfully_processed.snap
index 6079a4317..b4a6da3af 100644
--- a/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/task_successfully_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/fail_in_update_task_after_process_batch_success_for_document_addition/task_successfully_processed.snap
@@ -19,7 +19,8 @@ succeeded [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/after_batch_creation.snap b/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/after_batch_creation.snap
index c75a3b87e..3f34ca57b 100644
--- a/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/after_batch_creation.snap
+++ b/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/after_batch_creation.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 index_a [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_first_task.snap
index 656b06ad3..f17bfe38f 100644
--- a/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 index_a [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_second_task.snap b/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_second_task.snap
index 0cf82317b..75d5d8760 100644
--- a/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_second_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_second_task.snap
@@ -20,7 +20,7 @@ index_a [0,]
 index_b [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_third_task.snap b/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_third_task.snap
index 8b73d12c2..a69818dfa 100644
--- a/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_third_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/insert_task_while_another_task_is_processing/registered_the_third_task.snap
@@ -22,7 +22,7 @@ index_a [0,2,]
 index_b [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/index_creation_failed.snap b/index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/index_creation_failed.snap
index 60d8c4cdb..9100e5075 100644
--- a/index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/index_creation_failed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/index_creation_failed.snap
@@ -19,7 +19,7 @@ failed [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/registered_the_first_task.snap
index 63a2d606e..f252cc8ef 100644
--- a/index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/panic_in_process_batch_for_index_creation/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_first_task.snap
index 3a4705635..a34531f2a 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_first_task.snap
@@ -23,7 +23,8 @@ cattos [1,]
 doggos [0,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_second_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_second_task.snap
index 979ec8af6..f163ee3d7 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_second_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_second_task.snap
@@ -23,7 +23,9 @@ cattos [1,]
 doggos [0,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["cattos", "doggos"]
+cattos: { number_of_documents: 0, field_distribution: {} }
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_third_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_third_task.snap
index c7190dd8b..7e8db762f 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_third_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/processed_the_third_task.snap
@@ -23,7 +23,8 @@ cattos [1,]
 doggos [0,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["cattos"]
+cattos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_first_task.snap
index e23cd648f..1a29c1ac6 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_second_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_second_task.snap
index 82cc517cb..4020c2db0 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_second_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_second_task.snap
@@ -20,7 +20,7 @@ cattos [1,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_third_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_third_task.snap
index 76a6b3f08..f25280bc1 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_third_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_inserted_without_new_signal/registered_the_third_task.snap
@@ -22,7 +22,7 @@ cattos [1,]
 doggos [0,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/first.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/first.snap
index fa09eba28..d67c659c6 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/first.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/first.snap
@@ -23,7 +23,8 @@ succeeded [0,]
 doggos [0,1,2,3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/fourth.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/fourth.snap
index e52c36718..3d5c28e2c 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/fourth.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/fourth.snap
@@ -23,7 +23,8 @@ succeeded [0,1,2,3,]
 doggos [0,1,2,3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_first_task.snap
index 52866bed6..c2ad519fa 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_fourth_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_fourth_task.snap
index 6ac8aa79f..a9eb16d21 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_fourth_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_fourth_task.snap
@@ -22,7 +22,7 @@ enqueued [0,1,2,3,]
 doggos [0,1,2,3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_second_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_second_task.snap
index 32d32daaf..ad269dd7a 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_second_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_second_task.snap
@@ -20,7 +20,7 @@ enqueued [0,1,]
 doggos [0,1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_third_task.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_third_task.snap
index 75ceef14d..6267a840f 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_third_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/registered_the_third_task.snap
@@ -21,7 +21,7 @@ enqueued [0,1,2,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/second.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/second.snap
index 4b1577aa6..d45867c49 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/second.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/second.snap
@@ -23,7 +23,8 @@ succeeded [0,1,]
 doggos [0,1,2,3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/third.snap b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/third.snap
index 2ac3b141f..9705c5321 100644
--- a/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/third.snap
+++ b/index-scheduler/src/snapshots/lib.rs/process_tasks_without_autobatching/third.snap
@@ -23,7 +23,8 @@ succeeded [0,1,2,]
 doggos [0,1,2,3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/query_tasks_canceled_by/start.snap b/index-scheduler/src/snapshots/lib.rs/query_tasks_canceled_by/start.snap
index 624606ba9..b05f05d5d 100644
--- a/index-scheduler/src/snapshots/lib.rs/query_tasks_canceled_by/start.snap
+++ b/index-scheduler/src/snapshots/lib.rs/query_tasks_canceled_by/start.snap
@@ -26,7 +26,8 @@ catto [0,2,]
 doggo [1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 3 [1,2,]
diff --git a/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/processed_all_tasks.snap b/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/processed_all_tasks.snap
index 694bbff26..a07c46427 100644
--- a/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/processed_all_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/processed_all_tasks.snap
@@ -23,7 +23,10 @@ doggo [0,]
 whalo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto", "doggo", "whalo"]
+catto: { number_of_documents: 0, field_distribution: {} }
+doggo: { number_of_documents: 0, field_distribution: {} }
+whalo: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_first_task.snap
index c1a0899cd..8eb784c9b 100644
--- a/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggo [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_second_task.snap b/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_second_task.snap
index 6daa6bce2..776d699e1 100644
--- a/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_second_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_second_task.snap
@@ -20,7 +20,7 @@ doggo [0,]
 whalo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_third_task.snap b/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_third_task.snap
index 8427679e7..1a3fc5b53 100644
--- a/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_third_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/query_tasks_from_and_limit/registered_the_third_task.snap
@@ -22,7 +22,7 @@ doggo [0,]
 whalo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/query_tasks_simple/end.snap b/index-scheduler/src/snapshots/lib.rs/query_tasks_simple/end.snap
index 65838db64..fe3b1eed4 100644
--- a/index-scheduler/src/snapshots/lib.rs/query_tasks_simple/end.snap
+++ b/index-scheduler/src/snapshots/lib.rs/query_tasks_simple/end.snap
@@ -24,7 +24,9 @@ doggo [1,]
 whalo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto", "doggo"]
+catto: { number_of_documents: 0, field_distribution: {} }
+doggo: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/query_tasks_simple/start.snap b/index-scheduler/src/snapshots/lib.rs/query_tasks_simple/start.snap
index aed5aed8c..1fa3fa1ab 100644
--- a/index-scheduler/src/snapshots/lib.rs/query_tasks_simple/start.snap
+++ b/index-scheduler/src/snapshots/lib.rs/query_tasks_simple/start.snap
@@ -22,7 +22,7 @@ doggo [1,]
 whalo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/query_tasks_special_rules/start.snap b/index-scheduler/src/snapshots/lib.rs/query_tasks_special_rules/start.snap
index 2bb4f7590..4baa9d87a 100644
--- a/index-scheduler/src/snapshots/lib.rs/query_tasks_special_rules/start.snap
+++ b/index-scheduler/src/snapshots/lib.rs/query_tasks_special_rules/start.snap
@@ -24,7 +24,7 @@ doggo [1,2,]
 whalo [3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/register/everything_is_succesfully_registered.snap b/index-scheduler/src/snapshots/lib.rs/register/everything_is_succesfully_registered.snap
index 360752bc6..62796a929 100644
--- a/index-scheduler/src/snapshots/lib.rs/register/everything_is_succesfully_registered.snap
+++ b/index-scheduler/src/snapshots/lib.rs/register/everything_is_succesfully_registered.snap
@@ -23,7 +23,7 @@ catto [0,1,2,]
 doggo [3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_a.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_a.snap
index 2c009ef1a..47a6dc6a7 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_a.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_a.snap
@@ -25,7 +25,8 @@ c [2,]
 d [3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a"]
+a: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_b.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_b.snap
index 6d6e89c5f..13b783feb 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_b.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_b.snap
@@ -25,7 +25,9 @@ c [2,]
 d [3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_c.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_c.snap
index c12334ecf..6b4bdb756 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_c.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_c.snap
@@ -25,7 +25,10 @@ c [2,]
 d [3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_d.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_d.snap
index b20b3b320..038903c59 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_d.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/create_d.snap
@@ -25,7 +25,11 @@ c [2,]
 d [3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_processed.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_processed.snap
index 17e8936f0..c7ab30a36 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_processed.snap
@@ -28,7 +28,11 @@ c [3,4,5,]
 d [2,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_registered.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_registered.snap
index f2c74f676..c0727d6e9 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_registered.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/first_swap_registered.snap
@@ -27,7 +27,11 @@ c [2,4,]
 d [3,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/second_swap_processed.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/second_swap_processed.snap
index acfbc4c77..07acbe474 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/second_swap_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/second_swap_processed.snap
@@ -28,7 +28,11 @@ c [1,4,5,]
 d [2,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/third_empty_swap_processed.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/third_empty_swap_processed.snap
index c7c6faae6..aeeba29f8 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/third_empty_swap_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/third_empty_swap_processed.snap
@@ -29,7 +29,11 @@ c [1,4,5,]
 d [2,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes/two_swaps_registered.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes/two_swaps_registered.snap
index 0f8355f25..d1847fed1 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes/two_swaps_registered.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes/two_swaps_registered.snap
@@ -28,7 +28,11 @@ c [2,4,5,]
 d [3,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/after_the_index_creation.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/after_the_index_creation.snap
index b20b3b320..038903c59 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/after_the_index_creation.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/after_the_index_creation.snap
@@ -25,7 +25,11 @@ c [2,]
 d [3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/first_swap_failed.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/first_swap_failed.snap
index fd9790835..4632820f0 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/first_swap_failed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/first_swap_failed.snap
@@ -30,7 +30,11 @@ e [4,]
 f [4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/initial_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/initial_tasks_processed.snap
index b20b3b320..038903c59 100644
--- a/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/initial_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/swap_indexes_errors/initial_tasks_processed.snap
@@ -25,7 +25,11 @@ c [2,]
 d [3,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["a", "b", "c", "d"]
+a: { number_of_documents: 0, field_distribution: {} }
+b: { number_of_documents: 0, field_distribution: {} }
+c: { number_of_documents: 0, field_distribution: {} }
+d: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_enqueued.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_enqueued.snap
index fc37dcf2d..4b4a50bfb 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_enqueued.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_enqueued.snap
@@ -20,7 +20,7 @@ catto [0,]
 doggo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_processed.snap
index e4c4d9d7e..6e3a6e8ed 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/initial_tasks_processed.snap
@@ -21,7 +21,8 @@ catto [0,]
 doggo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/task_deletion_processed.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/task_deletion_processed.snap
index 8874cc9e0..c47a7a95f 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/task_deletion_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_delete_same_task_twice/task_deletion_processed.snap
@@ -22,7 +22,8 @@ succeeded [2,3,]
 doggo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/after_registering_the_task_deletion.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/after_registering_the_task_deletion.snap
index 3c3bd754e..302fd5f5e 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/after_registering_the_task_deletion.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/after_registering_the_task_deletion.snap
@@ -23,7 +23,8 @@ catto [0,]
 doggo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_enqueued.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_enqueued.snap
index fc37dcf2d..4b4a50bfb 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_enqueued.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_enqueued.snap
@@ -20,7 +20,7 @@ catto [0,]
 doggo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_processed.snap
index e4c4d9d7e..6e3a6e8ed 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/initial_tasks_processed.snap
@@ -21,7 +21,8 @@ catto [0,]
 doggo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/task_deletion_processed.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/task_deletion_processed.snap
index 29c251027..cf64406b8 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/task_deletion_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_deleteable/task_deletion_processed.snap
@@ -21,7 +21,8 @@ succeeded [2,]
 doggo [1,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/initial_tasks_enqueued.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/initial_tasks_enqueued.snap
index afb8af39c..25e2deadc 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/initial_tasks_enqueued.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/initial_tasks_enqueued.snap
@@ -22,7 +22,7 @@ catto [0,1,]
 doggo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_done.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_done.snap
index 6fc0a4f7c..743cd615f 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_done.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_done.snap
@@ -25,7 +25,7 @@ catto [0,1,]
 doggo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_enqueued.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_enqueued.snap
index e2ad01246..5c4d9be04 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_enqueued.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_enqueued.snap
@@ -24,7 +24,7 @@ catto [0,1,]
 doggo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_processing.snap b/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_processing.snap
index 8017f77b9..49df62cb7 100644
--- a/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_processing.snap
+++ b/index-scheduler/src/snapshots/lib.rs/task_deletion_undeleteable/task_deletion_processing.snap
@@ -24,7 +24,7 @@ catto [0,1,]
 doggo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/after_processing_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/after_processing_the_10_tasks.snap
index d112c8145..cb6ec63de 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/after_processing_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/after_processing_the_10_tasks.snap
@@ -30,7 +30,8 @@ succeeded [0,1,2,3,4,5,6,7,8,9,10,]
 doggos [0,1,2,3,4,5,6,7,8,9,10,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 10, field_distribution: {"doggo": 10, "id": 10} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/after_registering_the_10_tasks.snap
index 7daafcccb..2e4845fb4 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/after_registering_the_10_tasks.snap
@@ -30,7 +30,8 @@ succeeded [0,]
 doggos [0,1,2,3,4,5,6,7,8,9,10,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/processed_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/processed_the_first_task.snap
index ed265ac6e..e046ed386 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/processed_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/processed_the_first_task.snap
@@ -19,7 +19,8 @@ succeeded [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/registered_the_first_task.snap
index e23cd648f..1a29c1ac6 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/after_registering_the_10_tasks.snap
index 83f17bcef..e2e2133f5 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/after_registering_the_10_tasks.snap
@@ -30,7 +30,8 @@ succeeded [0,]
 doggos [0,1,2,3,4,5,6,7,8,9,10,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/all_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/all_tasks_processed.snap
index fc2fdc5f1..970587ba2 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/all_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/all_tasks_processed.snap
@@ -30,7 +30,8 @@ succeeded [0,1,2,3,4,5,6,7,8,9,10,]
 doggos [0,1,2,3,4,5,6,7,8,9,10,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 10, field_distribution: {"doggo": 10, "id": 10} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/five_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/five_tasks_processed.snap
index 48f972785..5de505cf2 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/five_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/five_tasks_processed.snap
@@ -30,7 +30,8 @@ succeeded [0,1,2,3,4,5,]
 doggos [0,1,2,3,4,5,6,7,8,9,10,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 5, field_distribution: {"doggo": 5, "id": 5} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/processed_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/processed_the_first_task.snap
index 6214f3139..606367737 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/processed_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/processed_the_first_task.snap
@@ -19,7 +19,8 @@ succeeded [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/registered_the_first_task.snap
index 52866bed6..c2ad519fa 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_with_index_without_autobatching/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index/after_processing_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index/after_processing_the_10_tasks.snap
index ed28c121b..5a6ea9100 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index/after_processing_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index/after_processing_the_10_tasks.snap
@@ -28,7 +28,7 @@ failed [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index/after_registering_the_10_tasks.snap
index 828d4dafc..e2217e1f4 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index/after_registering_the_10_tasks.snap
@@ -27,7 +27,7 @@ enqueued [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/after_registering_the_10_tasks.snap
index 671713c8e..02d0b1988 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/after_registering_the_10_tasks.snap
@@ -27,7 +27,7 @@ enqueued [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/all_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/all_tasks_processed.snap
index d995cab9e..8164394c8 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/all_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/all_tasks_processed.snap
@@ -28,7 +28,7 @@ failed [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/five_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/five_tasks_processed.snap
index 3ae875bff..4e0bb97ab 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/five_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_cant_create_index_without_index_without_autobatching/five_tasks_processed.snap
@@ -28,7 +28,7 @@ failed [0,1,2,3,4,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/after_registering_the_10_tasks.snap
index ad5968b58..f98802f21 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/after_registering_the_10_tasks.snap
@@ -27,7 +27,7 @@ enqueued [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/all_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/all_tasks_processed.snap
index 19ee47359..ea6ef400a 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/all_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/all_tasks_processed.snap
@@ -29,7 +29,8 @@ failed [0,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 9, field_distribution: {"doggo": 9, "id": 9} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/only_first_task_failed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/only_first_task_failed.snap
index ed57bc4e3..c27a1b5cb 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/only_first_task_failed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_right_without_index_starts_with_cant_create/only_first_task_failed.snap
@@ -28,7 +28,7 @@ failed [0,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/after_registering_the_10_tasks.snap
index 61b7f3016..68599f03e 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/after_registering_the_10_tasks.snap
@@ -30,7 +30,8 @@ succeeded [0,]
 doggos [0,1,2,3,4,5,6,7,8,9,10,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/all_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/all_tasks_processed.snap
index 0962dcdf5..b442a9c2f 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/all_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/all_tasks_processed.snap
@@ -30,7 +30,8 @@ succeeded [0,1,2,3,4,5,6,7,8,9,10,]
 doggos [0,1,2,3,4,5,6,7,8,9,10,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 10, field_distribution: {"doggo": 10, "id": 10} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/processed_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/processed_the_first_task.snap
index ed265ac6e..e046ed386 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/processed_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/processed_the_first_task.snap
@@ -19,7 +19,8 @@ succeeded [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/registered_the_first_task.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/registered_the_first_task.snap
index e23cd648f..1a29c1ac6 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/registered_the_first_task.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_mixed_rights_with_index/registered_the_first_task.snap
@@ -18,7 +18,7 @@ enqueued [0,]
 doggos [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/after_registering_the_5_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/after_registering_the_5_tasks.snap
index 53d3d28da..fde8e3451 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/after_registering_the_5_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/after_registering_the_5_tasks.snap
@@ -22,7 +22,7 @@ enqueued [0,1,2,3,4,]
 doggos [0,1,2,3,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/fifth_task_succeeds.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/fifth_task_succeeds.snap
index 58e16fa55..85d7ba460 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/fifth_task_succeeds.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/fifth_task_succeeds.snap
@@ -24,7 +24,8 @@ failed [0,1,3,]
 doggos [0,1,2,3,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 2, field_distribution: {"doggo": 2, "id": 2} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/first_and_second_task_fails.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/first_and_second_task_fails.snap
index 98bd2b580..ab788cc36 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/first_and_second_task_fails.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/first_and_second_task_fails.snap
@@ -23,7 +23,8 @@ failed [0,1,]
 doggos [0,1,2,3,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/fourth_task_fails.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/fourth_task_fails.snap
index 279040fdb..2a8748657 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/fourth_task_fails.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/fourth_task_fails.snap
@@ -24,7 +24,8 @@ failed [0,1,3,]
 doggos [0,1,2,3,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/third_task_succeeds.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/third_task_succeeds.snap
index 441bb59e2..58cdbe432 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/third_task_succeeds.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_bad_primary_key/third_task_succeeds.snap
@@ -24,7 +24,8 @@ failed [0,1,]
 doggos [0,1,2,3,4,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/after_registering_the_3_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/after_registering_the_3_tasks.snap
index cff9b0bd9..5699c58c4 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/after_registering_the_3_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/after_registering_the_3_tasks.snap
@@ -20,7 +20,7 @@ enqueued [0,1,2,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/only_first_task_succeed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/only_first_task_succeed.snap
index d3888af01..85689fa4d 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/only_first_task_succeed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/only_first_task_succeed.snap
@@ -21,7 +21,8 @@ succeeded [0,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/second_task_fails.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/second_task_fails.snap
index 84baeca92..18db64ca4 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/second_task_fails.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/second_task_fails.snap
@@ -22,7 +22,8 @@ failed [1,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/third_task_fails.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/third_task_fails.snap
index 6b92f91d1..4a9edc602 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/third_task_fails.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key/third_task_fails.snap
@@ -22,7 +22,8 @@ failed [1,2,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/after_registering_the_3_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/after_registering_the_3_tasks.snap
index 4c4f88a30..1187159b7 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/after_registering_the_3_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/after_registering_the_3_tasks.snap
@@ -20,7 +20,7 @@ enqueued [0,1,2,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/only_first_task_succeed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/only_first_task_succeed.snap
index 76b814eab..22b91bb60 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/only_first_task_succeed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/only_first_task_succeed.snap
@@ -21,7 +21,8 @@ succeeded [0,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/second_and_third_tasks_fails.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/second_and_third_tasks_fails.snap
index 26b0f6584..05eca0af1 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/second_and_third_tasks_fails.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_multiple_primary_key_batch_wrong_key/second_and_third_tasks_fails.snap
@@ -22,7 +22,8 @@ failed [1,]
 doggos [0,1,2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/after_registering_the_6_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/after_registering_the_6_tasks.snap
index 078ba06d3..47b0994ec 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/after_registering_the_6_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/after_registering_the_6_tasks.snap
@@ -23,7 +23,7 @@ enqueued [0,1,2,3,4,5,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/all_other_tasks_succeeds.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/all_other_tasks_succeeds.snap
index 69cbd3def..a7464685a 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/all_other_tasks_succeeds.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/all_other_tasks_succeeds.snap
@@ -25,7 +25,8 @@ failed [0,1,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 4, field_distribution: {"doggo": 4, "paw": 4} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/first_task_fails.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/first_task_fails.snap
index ac63f3b58..5c7f7e8d8 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/first_task_fails.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/first_task_fails.snap
@@ -24,7 +24,8 @@ failed [0,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/second_task_fails.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/second_task_fails.snap
index 538b4af93..2c255aeba 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/second_task_fails.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/second_task_fails.snap
@@ -24,7 +24,8 @@ failed [0,1,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/third_task_succeeds.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/third_task_succeeds.snap
index 1271b6f92..2f944adcf 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/third_task_succeeds.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key/third_task_succeeds.snap
@@ -25,7 +25,8 @@ failed [0,1,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "paw": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/after_registering_the_6_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/after_registering_the_6_tasks.snap
index 0e9ecb81a..c89abf033 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/after_registering_the_6_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/after_registering_the_6_tasks.snap
@@ -23,7 +23,7 @@ enqueued [0,1,2,3,4,5,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/all_other_tasks_succeeds.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/all_other_tasks_succeeds.snap
index 437c6375e..1f55e8f6d 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/all_other_tasks_succeeds.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/all_other_tasks_succeeds.snap
@@ -25,7 +25,8 @@ failed [1,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 5, field_distribution: {"doggo": 5, "doggoid": 5} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/first_task_succeed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/first_task_succeed.snap
index fd480420a..532cef143 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/first_task_succeed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/first_task_succeed.snap
@@ -24,7 +24,8 @@ succeeded [0,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "doggoid": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/second_task_fails.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/second_task_fails.snap
index 99001edb0..2920c3b2e 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/second_task_fails.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/second_task_fails.snap
@@ -25,7 +25,8 @@ failed [1,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 1, field_distribution: {"doggo": 1, "doggoid": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/third_task_succeeds.snap b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/third_task_succeeds.snap
index 64625ca90..8981dd8c3 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/third_task_succeeds.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_addition_with_set_and_null_primary_key_inference_works/third_task_succeeds.snap
@@ -25,7 +25,8 @@ failed [1,]
 doggos [0,1,2,3,4,5,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 2, field_distribution: {"doggo": 2, "doggoid": 2} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_replace/1.snap b/index-scheduler/src/snapshots/lib.rs/test_document_replace/1.snap
index a47ef319f..21581fe78 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_replace/1.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_replace/1.snap
@@ -27,7 +27,7 @@ enqueued [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_replace/2.snap b/index-scheduler/src/snapshots/lib.rs/test_document_replace/2.snap
index f6423719c..fabf764bc 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_replace/2.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_replace/2.snap
@@ -28,7 +28,8 @@ succeeded [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 10, field_distribution: {"doggo": 10, "id": 10} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/after_registering_the_10_tasks.snap
index 0f52c9664..1beba7264 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/after_registering_the_10_tasks.snap
@@ -27,7 +27,7 @@ enqueued [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/all_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/all_tasks_processed.snap
index b80b8bb40..a0b121320 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/all_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/all_tasks_processed.snap
@@ -28,7 +28,8 @@ succeeded [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 10, field_distribution: {"doggo": 10, "id": 10} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/five_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/five_tasks_processed.snap
index b1528c103..88bf59f8e 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/five_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_replace_without_autobatching/five_tasks_processed.snap
@@ -28,7 +28,8 @@ succeeded [0,1,2,3,4,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 5, field_distribution: {"doggo": 5, "id": 5} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_update/1.snap b/index-scheduler/src/snapshots/lib.rs/test_document_update/1.snap
index 6157fb454..53f0fbc9b 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_update/1.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_update/1.snap
@@ -27,7 +27,7 @@ enqueued [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_update/2.snap b/index-scheduler/src/snapshots/lib.rs/test_document_update/2.snap
index 736f998d0..d8383818e 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_update/2.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_update/2.snap
@@ -28,7 +28,8 @@ succeeded [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 10, field_distribution: {"doggo": 10, "id": 10} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/after_registering_the_10_tasks.snap
index 85fda1a43..6785786e3 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/after_registering_the_10_tasks.snap
@@ -27,7 +27,7 @@ enqueued [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/all_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/all_tasks_processed.snap
index a1fc55210..4c8fd7ea6 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/all_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/all_tasks_processed.snap
@@ -28,7 +28,8 @@ succeeded [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 10, field_distribution: {"doggo": 10, "id": 10} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/five_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/five_tasks_processed.snap
index fb0b629ec..f184bb3cb 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/five_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_document_update_without_autobatching/five_tasks_processed.snap
@@ -28,7 +28,8 @@ succeeded [0,1,2,3,4,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 5, field_distribution: {"doggo": 5, "id": 5} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/after_registering_the_10_tasks.snap b/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/after_registering_the_10_tasks.snap
index 330a3318e..9095f031b 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/after_registering_the_10_tasks.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/after_registering_the_10_tasks.snap
@@ -27,7 +27,7 @@ enqueued [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-[]
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/all_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/all_tasks_processed.snap
index 20fda049f..6c6fba517 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/all_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/all_tasks_processed.snap
@@ -28,7 +28,8 @@ succeeded [0,1,2,3,4,5,6,7,8,9,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 10, field_distribution: {"doggo": 10, "id": 10} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/five_tasks_processed.snap b/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/five_tasks_processed.snap
index 9fd990aa9..8aa7cfbea 100644
--- a/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/five_tasks_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/test_mixed_document_addition/five_tasks_processed.snap
@@ -28,7 +28,8 @@ succeeded [0,1,2,3,4,]
 doggos [0,1,2,3,4,5,6,7,8,9,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["doggos"]
+doggos: { number_of_documents: 5, field_distribution: {"doggo": 5, "id": 5} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 

From 076a3d371c733a0e90905038bde4626f3b9a21c6 Mon Sep 17 00:00:00 2001
From: Louis Dureuil <louis@meilisearch.com>
Date: Tue, 28 Feb 2023 15:24:31 +0100
Subject: [PATCH 3/6] Eagerly compute stats as fallback to the cache.

- Refactor all around to avoid spawning indexes more times than necessary
---
 index-scheduler/src/batch.rs            | 12 +++-
 index-scheduler/src/index_mapper/mod.rs | 83 +++++++++++++++++++------
 index-scheduler/src/lib.rs              |  5 ++
 meilisearch/src/routes/indexes/mod.rs   |  4 ++
 4 files changed, 83 insertions(+), 21 deletions(-)

diff --git a/index-scheduler/src/batch.rs b/index-scheduler/src/batch.rs
index 03287d7ae..41b5793b1 100644
--- a/index-scheduler/src/batch.rs
+++ b/index-scheduler/src/batch.rs
@@ -847,8 +847,10 @@ impl IndexScheduler {
                 // this is a non-critical operation. If it fails, we should not fail
                 // the entire batch.
                 let res = || -> Result<()> {
+                    let index_rtxn = index.read_txn()?;
+                    let stats = crate::index_mapper::IndexStats::new(&index, &index_rtxn)?;
                     let mut wtxn = self.env.write_txn()?;
-                    self.index_mapper.compute_and_store_stats_of(&mut wtxn, &index_uid)?;
+                    self.index_mapper.store_stats_of(&mut wtxn, &index_uid, stats)?;
                     wtxn.commit()?;
                     Ok(())
                 }();
@@ -888,6 +890,10 @@ impl IndexScheduler {
                     )?;
                     index_wtxn.commit()?;
                 }
+
+                // drop rtxn before starting a new wtxn on the same db
+                rtxn.commit()?;
+
                 task.status = Status::Succeeded;
                 task.details = Some(Details::IndexInfo { primary_key });
 
@@ -897,7 +903,9 @@ impl IndexScheduler {
                 // the entire batch.
                 let res = || -> Result<()> {
                     let mut wtxn = self.env.write_txn()?;
-                    self.index_mapper.compute_and_store_stats_of(&mut wtxn, &index_uid)?;
+                    let index_rtxn = index.read_txn()?;
+                    let stats = crate::index_mapper::IndexStats::new(&index, &index_rtxn)?;
+                    self.index_mapper.store_stats_of(&mut wtxn, &index_uid, stats)?;
                     wtxn.commit()?;
                     Ok(())
                 }();
diff --git a/index-scheduler/src/index_mapper/mod.rs b/index-scheduler/src/index_mapper/mod.rs
index 9e1de438a..174f4f9a3 100644
--- a/index-scheduler/src/index_mapper/mod.rs
+++ b/index-scheduler/src/index_mapper/mod.rs
@@ -54,8 +54,11 @@ pub struct IndexMapper {
 
     /// Map an index name with an index uuid currently available on disk.
     pub(crate) index_mapping: Database<Str, UuidCodec>,
-    /// Map an index name with the cached stats associated to the index.
-    pub(crate) index_stats: Database<Str, SerdeJson<IndexStats>>,
+    /// Map an index UUID with the cached stats associated to the index.
+    ///
+    /// Using an UUID forces to use the index_mapping table to recover the index behind a name, ensuring
+    /// consistency wrt index swapping.
+    pub(crate) index_stats: Database<UuidCodec, SerdeJson<IndexStats>>,
 
     /// Path to the folder where the LMDB environments of each index are.
     base_path: PathBuf,
@@ -80,15 +83,39 @@ pub enum IndexStatus {
     Available(Index),
 }
 
+/// The statistics that can be computed from an `Index` object.
 #[derive(Serialize, Deserialize, Debug)]
 pub struct IndexStats {
+    /// Number of documents in the index.
     pub number_of_documents: u64,
+    /// Size of the index' DB, in bytes.
     pub database_size: u64,
+    /// Association of every field name with the number of times it occurs in the documents.
     pub field_distribution: FieldDistribution,
+    /// Creation date of the index.
     pub created_at: OffsetDateTime,
+    /// Date of the last update of the index.
     pub updated_at: OffsetDateTime,
 }
 
+impl IndexStats {
+    /// Compute the stats of an index
+    ///
+    /// # Parameters
+    ///
+    /// - rtxn: a RO transaction for the index, obtained from `Index::read_txn()`.
+    pub fn new(index: &Index, rtxn: &RoTxn) -> Result<Self> {
+        let database_size = index.on_disk_size()?;
+        Ok(IndexStats {
+            number_of_documents: index.number_of_documents(rtxn)?,
+            database_size,
+            field_distribution: index.field_distribution(rtxn)?,
+            created_at: index.created_at(rtxn)?,
+            updated_at: index.updated_at(rtxn)?,
+        })
+    }
+}
+
 impl IndexMapper {
     pub fn new(
         env: &Env,
@@ -149,12 +176,14 @@ impl IndexMapper {
     /// 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<()> {
-        self.index_stats.delete(&mut wtxn, name)?;
         let uuid = self
             .index_mapping
             .get(&wtxn, name)?
             .ok_or_else(|| Error::IndexNotFound(name.to_string()))?;
 
+        // Not an error if the index had no stats in cache.
+        self.index_stats.delete(&mut wtxn, &uuid)?;
+
         // Once we retrieved the UUID of the index we remove it from the mapping table.
         assert!(self.index_mapping.delete(&mut wtxn, name)?);
 
@@ -375,26 +404,42 @@ impl IndexMapper {
         Ok(())
     }
 
-    /// Return the stored stats of an index.
+    /// The stats of an index.
+    ///
+    /// If available in the cache, they are directly returned.
+    /// Otherwise, the `Index` is opened to compute the stats on the fly (the result is not cached).
+    /// The stats for an index are cached after each `Index` update.
     pub fn stats_of(&self, rtxn: &RoTxn, index_uid: &str) -> Result<IndexStats> {
-        self.index_stats
+        let uuid = self
+            .index_mapping
             .get(rtxn, index_uid)?
-            .ok_or_else(|| Error::IndexNotFound(index_uid.to_string()))
+            .ok_or_else(|| Error::IndexNotFound(index_uid.to_string()))?;
+
+        match self.index_stats.get(rtxn, &uuid)? {
+            Some(stats) => Ok(stats),
+            None => {
+                let index = self.index(rtxn, index_uid)?;
+                let index_rtxn = index.read_txn()?;
+                IndexStats::new(&index, &index_rtxn)
+            }
+        }
     }
 
-    /// Return the stats of an index and write it in the index-mapper database.
-    pub fn compute_and_store_stats_of(&self, wtxn: &mut RwTxn, index_uid: &str) -> Result<()> {
-        let index = self.index(wtxn, index_uid)?;
-        let database_size = index.on_disk_size()?;
-        let rtxn = index.read_txn()?;
-        let stats = IndexStats {
-            number_of_documents: index.number_of_documents(&rtxn)?,
-            database_size,
-            field_distribution: index.field_distribution(&rtxn)?,
-            created_at: index.created_at(&rtxn)?,
-            updated_at: index.updated_at(&rtxn)?,
-        };
-        self.index_stats.put(wtxn, index_uid, &stats)?;
+    /// Stores the new stats for an index.
+    ///
+    /// Expected usage is to compute the stats the index using `IndexStats::new`, the pass it to this function.
+    pub fn store_stats_of(
+        &self,
+        wtxn: &mut RwTxn,
+        index_uid: &str,
+        stats: IndexStats,
+    ) -> Result<()> {
+        let uuid = self
+            .index_mapping
+            .get(wtxn, index_uid)?
+            .ok_or_else(|| Error::IndexNotFound(index_uid.to_string()))?;
+
+        self.index_stats.put(wtxn, &uuid, &stats)?;
         Ok(())
     }
 
diff --git a/index-scheduler/src/lib.rs b/index-scheduler/src/lib.rs
index 4f875eaca..7c5970fad 100644
--- a/index-scheduler/src/lib.rs
+++ b/index-scheduler/src/lib.rs
@@ -1245,9 +1245,14 @@ struct IndexBudget {
     task_db_size: usize,
 }
 
+/// The statistics that can be computed from an `Index` object and the scheduler.
+///
+/// Compared with `index_mapper::IndexStats`, it adds the scheduling status.
 #[derive(Debug)]
 pub struct IndexStats {
+    /// Whether this index is currently performing indexation, according to the scheduler.
     pub is_indexing: bool,
+    /// Internal stats computed from the index.
     pub inner_stats: index_mapper::IndexStats,
 }
 
diff --git a/meilisearch/src/routes/indexes/mod.rs b/meilisearch/src/routes/indexes/mod.rs
index 28988e30b..ba925b3d5 100644
--- a/meilisearch/src/routes/indexes/mod.rs
+++ b/meilisearch/src/routes/indexes/mod.rs
@@ -220,11 +220,15 @@ pub async fn delete_index(
     Ok(HttpResponse::Accepted().json(task))
 }
 
+/// Stats of an `Index`, as known to the `stats` route.
 #[derive(Serialize, Debug)]
 #[serde(rename_all = "camelCase")]
 pub struct IndexStats {
+    /// Number of documents in the index
     pub number_of_documents: u64,
+    /// Whether the index is currently performing indexation, according to the scheduler.
     pub is_indexing: bool,
+    /// Association of every field name with the number of times it occurs in the documents.
     pub field_distribution: FieldDistribution,
 }
 

From 76288fad72321531617b023425d71ec6461b000c Mon Sep 17 00:00:00 2001
From: Louis Dureuil <louis@meilisearch.com>
Date: Tue, 28 Feb 2023 15:36:25 +0100
Subject: [PATCH 4/6] Fix snapshots

---
 .../lib.rs/cancel_mix_of_tasks/aborted_indexation.snap       | 4 +++-
 .../lib.rs/cancel_mix_of_tasks/cancel_processed.snap         | 5 +++--
 .../lib.rs/cancel_processing_task/aborted_indexation.snap    | 3 ++-
 .../lib.rs/cancel_processing_task/cancel_processed.snap      | 4 ++--
 4 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/aborted_indexation.snap b/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/aborted_indexation.snap
index 5c6078b51..112cd597b 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/aborted_indexation.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/aborted_indexation.snap
@@ -25,7 +25,9 @@ catto [0,]
 wolfo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["beavero", "catto"]
+beavero: { number_of_documents: 0, field_distribution: {} }
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/cancel_processed.snap b/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/cancel_processed.snap
index f67fff59f..1e5182f80 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/cancel_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_mix_of_tasks/cancel_processed.snap
@@ -1,6 +1,5 @@
 ---
 source: index-scheduler/src/lib.rs
-assertion_line: 1859
 ---
 ### Autobatching Enabled = true
 ### Processing Tasks:
@@ -27,7 +26,9 @@ catto [0,]
 wolfo [2,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["beavero", "catto"]
+beavero: { number_of_documents: 0, field_distribution: {} }
+catto: { number_of_documents: 1, field_distribution: {"id": 1} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 3 [1,2,]
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/aborted_indexation.snap b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/aborted_indexation.snap
index 6074673e3..a2187ab2b 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/aborted_indexation.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/aborted_indexation.snap
@@ -20,7 +20,8 @@ enqueued [0,1,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 
diff --git a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_processed.snap b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_processed.snap
index f2035c7fe..0ede1ffd3 100644
--- a/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_processed.snap
+++ b/index-scheduler/src/snapshots/lib.rs/cancel_processing_task/cancel_processed.snap
@@ -1,6 +1,5 @@
 ---
 source: index-scheduler/src/lib.rs
-assertion_line: 1818
 ---
 ### Autobatching Enabled = true
 ### Processing Tasks:
@@ -23,7 +22,8 @@ canceled [0,]
 catto [0,]
 ----------------------------------------------------------------------
 ### Index Mapper:
-["catto"]
+catto: { number_of_documents: 0, field_distribution: {} }
+
 ----------------------------------------------------------------------
 ### Canceled By:
 1 [0,]

From 7faa9a22f6d398496fe6fc07028763a55c9466e1 Mon Sep 17 00:00:00 2001
From: Louis Dureuil <louis@meilisearch.com>
Date: Tue, 7 Mar 2023 14:00:54 +0100
Subject: [PATCH 5/6] Pass IndexStat by ref in store_stats_of

---
 index-scheduler/src/batch.rs            | 4 ++--
 index-scheduler/src/index_mapper/mod.rs | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/index-scheduler/src/batch.rs b/index-scheduler/src/batch.rs
index 41b5793b1..8d0e1ac3f 100644
--- a/index-scheduler/src/batch.rs
+++ b/index-scheduler/src/batch.rs
@@ -850,7 +850,7 @@ impl IndexScheduler {
                     let index_rtxn = index.read_txn()?;
                     let stats = crate::index_mapper::IndexStats::new(&index, &index_rtxn)?;
                     let mut wtxn = self.env.write_txn()?;
-                    self.index_mapper.store_stats_of(&mut wtxn, &index_uid, stats)?;
+                    self.index_mapper.store_stats_of(&mut wtxn, &index_uid, &stats)?;
                     wtxn.commit()?;
                     Ok(())
                 }();
@@ -905,7 +905,7 @@ impl IndexScheduler {
                     let mut wtxn = self.env.write_txn()?;
                     let index_rtxn = index.read_txn()?;
                     let stats = crate::index_mapper::IndexStats::new(&index, &index_rtxn)?;
-                    self.index_mapper.store_stats_of(&mut wtxn, &index_uid, stats)?;
+                    self.index_mapper.store_stats_of(&mut wtxn, &index_uid, &stats)?;
                     wtxn.commit()?;
                     Ok(())
                 }();
diff --git a/index-scheduler/src/index_mapper/mod.rs b/index-scheduler/src/index_mapper/mod.rs
index 174f4f9a3..2bf6f46ad 100644
--- a/index-scheduler/src/index_mapper/mod.rs
+++ b/index-scheduler/src/index_mapper/mod.rs
@@ -432,14 +432,14 @@ impl IndexMapper {
         &self,
         wtxn: &mut RwTxn,
         index_uid: &str,
-        stats: IndexStats,
+        stats: &IndexStats,
     ) -> Result<()> {
         let uuid = self
             .index_mapping
             .get(wtxn, index_uid)?
             .ok_or_else(|| Error::IndexNotFound(index_uid.to_string()))?;
 
-        self.index_stats.put(wtxn, &uuid, &stats)?;
+        self.index_stats.put(wtxn, &uuid, stats)?;
         Ok(())
     }
 

From 2f5b9fbbd83cf919f18749d632d046b1e7c75c2a Mon Sep 17 00:00:00 2001
From: Louis Dureuil <louis@meilisearch.com>
Date: Tue, 7 Mar 2023 14:05:27 +0100
Subject: [PATCH 6/6] Restore contribution of the index sizes to the db size

- the index size now contributes to the db size even if the index is not authorized
---
 meilisearch/src/routes/mod.rs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/meilisearch/src/routes/mod.rs b/meilisearch/src/routes/mod.rs
index f54c8ee38..c824d3f36 100644
--- a/meilisearch/src/routes/mod.rs
+++ b/meilisearch/src/routes/mod.rs
@@ -260,13 +260,17 @@ pub fn create_all_stats(
     let mut indexes = BTreeMap::new();
     let mut database_size = 0;
 
-    // accumulate the size of each indexes
     for index_uid in index_scheduler.index_names()? {
+        // Accumulate the size of all indexes, even unauthorized ones, so
+        // as to return a database_size representative of the correct database size on disk.
+        // See <https://github.com/meilisearch/meilisearch/pull/3541#discussion_r1126747643> for context.
+        let stats = index_scheduler.index_stats(&index_uid)?;
+        database_size += stats.inner_stats.database_size;
+
         if !filters.is_index_authorized(&index_uid) {
             continue;
         }
 
-        let stats = index_scheduler.index_stats(&index_uid)?;
         last_task = last_task.map_or(Some(stats.inner_stats.updated_at), |last| {
             Some(last.max(stats.inner_stats.updated_at))
         });