WIP

Cargo.lock

@@ -3254,8 +3254,10 @@ dependencies = [
  "enum-iterator",
  "file-store",
  "flate2",
+ "hashbrown 0.15.5",
  "indexmap",
  "insta",
+ "itertools 0.14.0",
  "maplit",
  "meili-snap",
  "meilisearch-auth",
@@ -3270,6 +3272,7 @@ dependencies = [
  "tempfile",
  "thiserror 2.0.16",
  "time",
+ "tokio",
  "tracing",
  "ureq",
  "uuid",

crates/dump/src/lib.rs

@@ -158,6 +158,10 @@ pub enum KindDump {
     UpgradeDatabase {
         from: (u32, u32, u32),
     },
+    NetworkTopologyChange {
+        network: Option<meilisearch_types::enterprise_edition::network::Network>,
+        origin: Option<meilisearch_types::tasks::Origin>,
+    },
 }
 
 impl From<Task> for TaskDump {
@@ -240,6 +244,9 @@ impl From<KindWithContent> for KindDump {
             KindWithContent::UpgradeDatabase { from: version } => {
                 KindDump::UpgradeDatabase { from: version }
             }
+            KindWithContent::NetworkTopologyChange { network, origin } => {
+                KindDump::NetworkTopologyChange { network, origin }
+            }
         }
     }
 }
@@ -253,7 +260,7 @@ pub(crate) mod test {
     use big_s::S;
     use maplit::{btreemap, btreeset};
     use meilisearch_types::batches::{Batch, BatchEnqueuedAt, BatchStats};
-    use meilisearch_types::enterprise_edition::network::{Network, Remote};
+    use meilisearch_types::enterprise_edition::network::{DbNetwork, DbRemote};
     use meilisearch_types::facet_values_sort::FacetValuesSort;
     use meilisearch_types::features::RuntimeTogglableFeatures;
     use meilisearch_types::index_uid_pattern::IndexUidPattern;
@@ -544,10 +551,10 @@ pub(crate) mod test {
         RuntimeTogglableFeatures::default()
     }
 
-    fn create_test_network() -> Network {
-        Network {
+    fn create_test_network() -> DbNetwork {
+        DbNetwork {
             local: Some("myself".to_string()),
-            remotes: maplit::btreemap! {"other".to_string() => Remote { url: "http://test".to_string(), search_api_key: Some("apiKey".to_string()), write_api_key: Some("docApiKey".to_string()) }},
+            remotes: maplit::btreemap! {"other".to_string() => DbRemote { url: "http://test".to_string(), search_api_key: Some("apiKey".to_string()), write_api_key: Some("docApiKey".to_string()) }},
             sharding: false,
         }
     }

crates/dump/src/reader/v6/mod.rs

@@ -24,7 +24,7 @@ pub type Batch = meilisearch_types::batches::Batch;
 pub type Key = meilisearch_types::keys::Key;
 pub type ChatCompletionSettings = meilisearch_types::features::ChatCompletionSettings;
 pub type RuntimeTogglableFeatures = meilisearch_types::features::RuntimeTogglableFeatures;
-pub type Network = meilisearch_types::enterprise_edition::network::Network;
+pub type Network = meilisearch_types::enterprise_edition::network::DbNetwork;
 pub type Webhooks = meilisearch_types::webhooks::WebhooksDumpView;
 
 // ===== Other types to clarify the code of the compat module

crates/dump/src/writer.rs

@@ -5,7 +5,7 @@ use std::path::PathBuf;
 use flate2::write::GzEncoder;
 use flate2::Compression;
 use meilisearch_types::batches::Batch;
-use meilisearch_types::enterprise_edition::network::Network;
+use meilisearch_types::enterprise_edition::network::DbNetwork;
 use meilisearch_types::features::{ChatCompletionSettings, RuntimeTogglableFeatures};
 use meilisearch_types::keys::Key;
 use meilisearch_types::settings::{Checked, Settings};
@@ -72,7 +72,7 @@ impl DumpWriter {
         )?)
     }
 
-    pub fn create_network(&self, network: Network) -> Result<()> {
+    pub fn create_network(&self, network: DbNetwork) -> Result<()> {
         Ok(std::fs::write(self.dir.path().join("network.json"), serde_json::to_string(&network)?)?)
     }
 

crates/index-scheduler/Cargo.toml

@@ -23,6 +23,7 @@ dump = { path = "../dump" }
 enum-iterator = "2.1.0"
 file-store = { path = "../file-store" }
 flate2 = "1.1.2"
+hashbrown = "0.15.4"
 indexmap = "2.9.0"
 meilisearch-auth = { path = "../meilisearch-auth" }
 meilisearch-types = { path = "../meilisearch-types" }
@@ -45,6 +46,8 @@ tracing = "0.1.41"
 ureq = "2.12.1"
 uuid = { version = "1.17.0", features = ["serde", "v4"] }
 backoff = "0.4.0"
+itertools = "0.14.0"
+tokio = { version = "1.47.1", features = ["full"] }
 
 [dev-dependencies]
 big_s = "1.0.2"

crates/index-scheduler/src/dump.rs

@@ -234,6 +234,9 @@ impl<'a> Dump<'a> {
                     }
                 }
                 KindDump::UpgradeDatabase { from } => KindWithContent::UpgradeDatabase { from },
+                KindDump::NetworkTopologyChange { network: new_network, origin } => {
+                    KindWithContent::NetworkTopologyChange { network: new_network, origin }
+                }
             },
         };
 

crates/index-scheduler/src/features.rs

@@ -1,6 +1,6 @@
 use std::sync::{Arc, RwLock};
 
-use meilisearch_types::enterprise_edition::network::Network;
+use meilisearch_types::enterprise_edition::network::DbNetwork;
 use meilisearch_types::features::{InstanceTogglableFeatures, RuntimeTogglableFeatures};
 use meilisearch_types::heed::types::{SerdeJson, Str};
 use meilisearch_types::heed::{Database, Env, RwTxn, WithoutTls};
@@ -24,7 +24,7 @@ mod db_keys {
 pub(crate) struct FeatureData {
     persisted: Database<Str, SerdeJson<RuntimeTogglableFeatures>>,
     runtime: Arc<RwLock<RuntimeTogglableFeatures>>,
-    network: Arc<RwLock<Network>>,
+    network: Arc<RwLock<DbNetwork>>,
 }
 
 #[derive(Debug, Clone, Copy)]
@@ -197,8 +197,8 @@ impl FeatureData {
         }));
 
         // Once this is stabilized, network should be stored along with webhooks in index-scheduler's persisted database
-        let network_db = runtime_features_db.remap_data_type::<SerdeJson<Network>>();
-        let network: Network = network_db.get(wtxn, db_keys::NETWORK)?.unwrap_or_default();
+        let network_db = runtime_features_db.remap_data_type::<SerdeJson<DbNetwork>>();
+        let network: DbNetwork = network_db.get(wtxn, db_keys::NETWORK)?.unwrap_or_default();
 
         Ok(Self {
             persisted: runtime_features_db,
@@ -234,8 +234,8 @@ impl FeatureData {
         RoFeatures::new(self)
     }
 
-    pub fn put_network(&self, mut wtxn: RwTxn, new_network: Network) -> Result<()> {
-        self.persisted.remap_data_type::<SerdeJson<Network>>().put(
+    pub fn put_network(&self, mut wtxn: RwTxn, new_network: DbNetwork) -> Result<()> {
+        self.persisted.remap_data_type::<SerdeJson<DbNetwork>>().put(
             &mut wtxn,
             db_keys::NETWORK,
             &new_network,
@@ -247,7 +247,7 @@ impl FeatureData {
         Ok(())
     }
 
-    pub fn network(&self) -> Network {
-        Network::clone(&*self.network.read().unwrap())
+    pub fn network(&self) -> DbNetwork {
+        DbNetwork::clone(&*self.network.read().unwrap())
     }
 }

crates/index-scheduler/src/insta_snapshot.rs

@@ -36,6 +36,7 @@ pub fn snapshot_index_scheduler(scheduler: &IndexScheduler) -> String {
         run_loop_iteration: _,
         embedders: _,
         chat_settings: _,
+        runtime: _,
     } = scheduler;
 
     let rtxn = env.read_txn().unwrap();
@@ -317,6 +318,9 @@ fn snapshot_details(d: &Details) -> String {
         Details::UpgradeDatabase { from, to } => {
             format!("{{ from: {from:?}, to: {to:?} }}")
         }
+        Details::NetworkTopologyChange { network: new_network } => {
+            format!("{{ new_network: {new_network:?} }}")
+        }
     }
 }
 

crates/index-scheduler/src/lib.rs

@@ -54,7 +54,7 @@ pub use features::RoFeatures;
 use flate2::bufread::GzEncoder;
 use flate2::Compression;
 use meilisearch_types::batches::Batch;
-use meilisearch_types::enterprise_edition::network::Network;
+use meilisearch_types::enterprise_edition::network::DbNetwork;
 use meilisearch_types::features::{
     ChatCompletionSettings, InstanceTogglableFeatures, RuntimeTogglableFeatures,
 };
@@ -216,6 +216,8 @@ pub struct IndexScheduler {
     /// A counter that is incremented before every call to [`tick`](IndexScheduler::tick)
     #[cfg(test)]
     run_loop_iteration: Arc<RwLock<usize>>,
+
+    runtime: Option<tokio::runtime::Handle>,
 }
 
 impl IndexScheduler {
@@ -242,6 +244,7 @@ impl IndexScheduler {
             run_loop_iteration: self.run_loop_iteration.clone(),
             features: self.features.clone(),
             chat_settings: self.chat_settings,
+            runtime: self.runtime.clone(),
         }
     }
 
@@ -260,6 +263,7 @@ impl IndexScheduler {
         options: IndexSchedulerOptions,
         auth_env: Env<WithoutTls>,
         from_db_version: (u32, u32, u32),
+        runtime: Option<tokio::runtime::Handle>,
         #[cfg(test)] test_breakpoint_sdr: crossbeam_channel::Sender<(test_utils::Breakpoint, bool)>,
         #[cfg(test)] planned_failures: Vec<(usize, test_utils::FailureLocation)>,
     ) -> Result<Self> {
@@ -341,6 +345,7 @@ impl IndexScheduler {
             run_loop_iteration: Arc::new(RwLock::new(0)),
             features,
             chat_settings,
+            runtime,
         };
 
         this.run();
@@ -892,13 +897,13 @@ impl IndexScheduler {
         Ok(())
     }
 
-    pub fn put_network(&self, network: Network) -> Result<()> {
+    pub fn put_network(&self, network: DbNetwork) -> Result<()> {
         let wtxn = self.env.write_txn().map_err(Error::HeedTransaction)?;
         self.features.put_network(wtxn, network)?;
         Ok(())
     }
 
-    pub fn network(&self) -> Network {
+    pub fn network(&self) -> DbNetwork {
         self.features.network()
     }
 
@@ -927,9 +932,10 @@ impl IndexScheduler {
 
     pub fn embedders(
         &self,
-        index_uid: String,
+        index_uid: &str,
         embedding_configs: Vec<IndexEmbeddingConfig>,
     ) -> Result<RuntimeEmbedders> {
+        let err = |err| Error::from_milli(err, Some(index_uid.to_owned()));
         let res: Result<_> = embedding_configs
             .into_iter()
             .map(
@@ -942,7 +948,7 @@ impl IndexScheduler {
                     let document_template = prompt
                         .try_into()
                         .map_err(meilisearch_types::milli::Error::from)
-                        .map_err(|err| Error::from_milli(err, Some(index_uid.clone())))?;
+                        .map_err(err)?;
 
                     let fragments = fragments
                         .into_inner()
@@ -972,9 +978,8 @@ impl IndexScheduler {
                     let embedder = Arc::new(
                         Embedder::new(embedder_options.clone(), self.scheduler.embedding_cache_cap)
                             .map_err(meilisearch_types::milli::vector::Error::from)
-                            .map_err(|err| {
-                                Error::from_milli(err.into(), Some(index_uid.clone()))
-                            })?,
+                            .map_err(milli::Error::from)
+                            .map_err(err)?,
                     );
                     {
                         let mut embedders = self.embedders.write().unwrap();

crates/index-scheduler/src/scheduler/autobatcher.rs

@@ -73,6 +73,7 @@ impl From<KindWithContent> for AutobatchKind {
             | KindWithContent::DumpCreation { .. }
             | KindWithContent::Export { .. }
             | KindWithContent::UpgradeDatabase { .. }
+            | KindWithContent::NetworkTopologyChange { .. }
             | KindWithContent::SnapshotCreation => {
                 panic!("The autobatcher should never be called with tasks that don't apply to an index.")
             }
@@ -287,7 +288,7 @@ impl BatchKind {
         };
 
         match (self, autobatch_kind) {
-            // We don't batch any of these operations  
+            // We don't batch any of these operations
             (this, K::IndexCreation | K::IndexUpdate | K::IndexSwap | K::DocumentEdition) => Break((this, BatchStopReason::TaskCannotBeBatched { kind, id })),
             // We must not batch tasks that don't have the same index creation rights if the index doesn't already exists.
             (this, kind) if !index_already_exists && this.allow_index_creation() == Some(false) && kind.allow_index_creation() == Some(true) => {

crates/index-scheduler/src/scheduler/create_batch.rs

@@ -55,6 +55,9 @@ pub(crate) enum Batch {
     UpgradeDatabase {
         tasks: Vec<Task>,
     },
+    NetworkTopologyChanges {
+        tasks: Vec<Task>,
+    },
 }
 
 #[derive(Debug)]
@@ -116,7 +119,8 @@ impl Batch {
             Batch::SnapshotCreation(tasks)
             | Batch::TaskDeletions(tasks)
             | Batch::UpgradeDatabase { tasks }
-            | Batch::IndexDeletion { tasks, .. } => {
+            | Batch::IndexDeletion { tasks, .. }
+            | Batch::NetworkTopologyChanges { tasks } => {
                 RoaringBitmap::from_iter(tasks.iter().map(|task| task.uid))
             }
             Batch::IndexOperation { op, .. } => match op {
@@ -151,6 +155,7 @@ impl Batch {
             | Dump(_)
             | Export { .. }
             | UpgradeDatabase { .. }
+            | NetworkTopologyChanges { .. }
             | IndexSwap { .. } => None,
             IndexOperation { op, .. } => Some(op.index_uid()),
             IndexCreation { index_uid, .. }
@@ -176,6 +181,7 @@ impl fmt::Display for Batch {
             Batch::IndexDeletion { .. } => f.write_str("IndexDeletion")?,
             Batch::IndexSwap { .. } => f.write_str("IndexSwap")?,
             Batch::Export { .. } => f.write_str("Export")?,
+            Batch::NetworkTopologyChanges { .. } => f.write_str("NetworkTopologyChange")?,
             Batch::UpgradeDatabase { .. } => f.write_str("UpgradeDatabase")?,
         };
         match index_uid {
@@ -545,7 +551,18 @@ impl IndexScheduler {
             return Ok(Some((Batch::Dump(task), current_batch)));
         }
 
-        // 6. We make a batch from the unprioritised tasks. Start by taking the next enqueued task.
+        // 6. We batch the network changes.
+        let to_network = self.queue.tasks.get_kind(rtxn, Kind::NetworkTopologyChange)? & enqueued;
+        if !to_network.is_empty() {
+            let mut tasks = self.queue.tasks.get_existing_tasks(rtxn, to_network)?;
+            current_batch.processing(&mut tasks);
+            current_batch.reason(BatchStopReason::TaskKindCannotBeBatched {
+                kind: Kind::NetworkTopologyChange,
+            });
+            return Ok(Some((Batch::NetworkTopologyChanges { tasks }, current_batch)));
+        }
+
+        // 7. We make a batch from the unprioritised tasks. Start by taking the next enqueued task.
         let task_id = if let Some(task_id) = enqueued.min() { task_id } else { return Ok(None) };
         let mut task =
             self.queue.tasks.get_task(rtxn, task_id)?.ok_or(Error::CorruptedTaskQueue)?;

crates/index-scheduler/src/scheduler/enterprise_edition/mod.rs

@@ -0,0 +1,6 @@
+// Copyright © 2025 Meilisearch Some Rights Reserved
+// This file is part of Meilisearch Enterprise Edition (EE).
+// Use of this source code is governed by the Business Source License 1.1,
+// as found in the LICENSE-EE file or at <https://mariadb.com/bsl11>
+
+mod process_network;

crates/index-scheduler/src/scheduler/enterprise_edition/process_network.rs

@@ -0,0 +1,362 @@
+// Copyright © 2025 Meilisearch Some Rights Reserved
+// This file is part of Meilisearch Enterprise Edition (EE).
+// Use of this source code is governed by the Business Source License 1.1,
+// as found in the LICENSE-EE file or at <https://mariadb.com/bsl11>
+
+use std::collections::BTreeMap;
+use std::time::Duration;
+
+use bumpalo::Bump;
+use itertools::{EitherOrBoth, Itertools};
+use meilisearch_types::enterprise_edition::network::{DbNetwork, DbRemote, Network, Remote};
+use meilisearch_types::milli::documents::PrimaryKey;
+use meilisearch_types::milli::progress::{EmbedderStats, Progress};
+use meilisearch_types::milli::update::new::indexer;
+use meilisearch_types::milli::update::Setting;
+use meilisearch_types::milli::{self};
+use meilisearch_types::tasks::{KindWithContent, Status, Task};
+use roaring::RoaringBitmap;
+
+use crate::scheduler::process_export::{ExportContext, ExportOptions, TargetInstance};
+use crate::{Error, IndexScheduler};
+
+impl IndexScheduler {
+    pub(crate) fn process_network_changes(
+        &self,
+        progress: Progress,
+        mut tasks: Vec<Task>,
+    ) -> crate::Result<Vec<Task>> {
+        let old_network = self.network();
+        let mut current_network = Some(old_network.clone());
+        for task in &tasks {
+            let KindWithContent::NetworkTopologyChange { network, origin } = &task.kind else {
+                continue;
+            };
+            current_network = match (current_network, network) {
+                (None, None) => None,
+                (None, Some(network)) => Some(accumulate(DbNetwork::default(), network.clone())?),
+                (Some(current_network), None) => Some(current_network),
+                (Some(current_network), Some(new_network)) => {
+                    Some(accumulate(current_network, new_network.clone())?)
+                }
+            };
+        }
+
+        'network: {
+            let mut new_network = current_network.unwrap_or_default();
+            if old_network == new_network {
+                // no change, exit
+                break 'network;
+            }
+
+            /// TODO: only do this if the task originates with an end-user
+            let must_replicate = old_network.sharding || new_network.sharding;
+
+            if !must_replicate {
+                self.put_network(new_network)?;
+                break 'network;
+            }
+
+            let must_stop_processing = &self.scheduler.must_stop_processing;
+
+            /// FIXME: make it mandatory for `self` to be part of the network
+            let old_this = old_network.local.as_deref();
+            /// FIXME: error here
+            let new_this = new_network.local.unwrap();
+
+            // in network replication, we need to tell old nodes that they are no longer part of the network.
+            // This is made difficult by "node aliasing": Meilisearch has no way of knowing if two nodes with different names
+            // or even different URLs actually refer to the same machine in two different versions of the network.
+            //
+            // This implementation ignores aliasing: a node is the same when it has the same name.
+            //
+            // To defeat aliasing, we iterate a first time to collect all deletions and additions, then we make sure to process the deletions
+            // first, rather than processing the tasks in the alphalexical order of remotes.
+            let mut node_deletions = Vec::new();
+            let mut node_additions = Vec::new();
+            for eob in old_network
+                .remotes
+                .iter()
+                .merge_join_by(new_network.remotes.iter(), |(left, _), (right, _)| left.cmp(right))
+            {
+                match eob {
+                    EitherOrBoth::Both((to_update_name, _), (_, new_node)) => {
+                        if to_update_name.as_str() == new_this {
+                            continue; // skip `self`
+                        }
+                        node_additions.push((to_update_name, new_node));
+                    }
+                    EitherOrBoth::Left((to_delete_name, to_delete_node)) => {
+                        if Some(to_delete_name.as_str()) == old_this {
+                            continue; // skip `self`
+                        }
+                        node_deletions.push((to_delete_name, to_delete_node));
+                    }
+                    EitherOrBoth::Right((to_add_name, to_add_node)) => {
+                        if to_add_name.as_str() == new_this {
+                            continue; // skip `self`
+                        }
+                        node_additions.push((to_add_name, to_add_node));
+                    }
+                }
+            }
+
+            let runtime = self.runtime.clone().unwrap();
+            let mut in_flight = Vec::new();
+            // process deletions
+            for (to_delete_name, to_delete) in node_deletions {
+                // set `self` to None so that this node is forgotten about
+                new_network.local = None;
+                in_flight.push(proxy_network(&runtime, to_delete.url.as_str(), &new_network)?);
+            }
+
+            runtime.block_on(async {
+                for task in in_flight.drain(..) {
+                    // TODO: log and ignore errors during deletion
+                    let res = task.await;
+                }
+            });
+
+            // process additions
+            for (to_add_name, to_add) in node_additions {
+                new_network.local = Some(to_add_name.clone());
+                in_flight.push(proxy_network(&runtime, to_add.url.as_str(), &new_network)?);
+            }
+
+            runtime.block_on(async {
+                for task in in_flight.drain(..) {
+                    // TODO: handle errors during addition
+                    let res = task.await;
+                }
+            });
+
+            // balance documents
+            new_network.local = Some(new_this);
+
+            self.balance_documents(&new_network, &progress, &must_stop_processing)?;
+
+            self.put_network(new_network)?;
+        }
+
+        for task in &mut tasks {
+            task.status = Status::Succeeded;
+        }
+        Ok(tasks)
+    }
+
+    fn balance_documents(
+        &self,
+        new_network: &DbNetwork,
+        progress: &Progress,
+        must_stop_processing: &crate::scheduler::MustStopProcessing,
+    ) -> crate::Result<()> {
+        /// FIXME unwrap
+        let new_shards = new_network.shards().unwrap();
+
+        // TECHDEBT: this spawns a `ureq` agent additionally to `reqwest`. We probably want to harmonize all of this.
+        let agent = ureq::AgentBuilder::new().timeout(Duration::from_secs(5)).build();
+
+        let mut indexer_alloc = Bump::new();
+
+        // process by batches of 20MiB. Allow for compression? Don't forget about embeddings
+        let _: Vec<()> = self.try_for_each_index(|index_uid, index| -> crate::Result<()> {
+            indexer_alloc.reset();
+            let err = |err| Error::from_milli(err, Some(index_uid.to_string()));
+            let index_rtxn = index.read_txn()?;
+            let all_docids = index.external_documents_ids();
+            let mut documents_to_move_to: hashbrown::HashMap<String, RoaringBitmap> =
+                hashbrown::HashMap::new();
+            let mut documents_to_delete = RoaringBitmap::new();
+
+            for res in all_docids.iter(&index_rtxn)? {
+                let (external_docid, docid) = res?;
+                match new_shards.processing_shard(external_docid) {
+                    Some(shard) if shard.is_own => continue,
+                    Some(shard) => {
+                        documents_to_move_to
+                            .entry_ref(shard.name.as_str())
+                            .or_default()
+                            .insert(docid);
+                    }
+                    None => {
+                        documents_to_delete.insert(docid);
+                    }
+                }
+            }
+
+            let fields_ids_map = index.fields_ids_map(&index_rtxn)?;
+
+            for (remote, documents_to_move) in documents_to_move_to {
+                /// TODO: justify the unwrap
+                let remote = new_network.remotes.get(&remote).unwrap();
+
+                let target = TargetInstance {
+                    base_url: &remote.url,
+                    api_key: remote.write_api_key.as_deref(),
+                };
+                let options = ExportOptions {
+                    index_uid,
+                    payload_size: None,
+                    override_settings: false,
+                    extra_headers: &Default::default(),
+                };
+                let ctx = ExportContext {
+                    index,
+                    index_rtxn: &index_rtxn,
+                    universe: &documents_to_move,
+                    progress,
+                    agent: &agent,
+                    must_stop_processing,
+                };
+
+                self.export_one_index(target, options, ctx)?;
+
+                documents_to_delete |= documents_to_move;
+            }
+
+            if documents_to_delete.is_empty() {
+                return Ok(());
+            }
+
+            let mut new_fields_ids_map = fields_ids_map.clone();
+
+            // candidates not empty => index not empty => a primary key is set
+            let primary_key = index.primary_key(&index_rtxn)?.unwrap();
+
+            let primary_key = PrimaryKey::new_or_insert(primary_key, &mut new_fields_ids_map)
+                .map_err(milli::Error::from)
+                .map_err(err)?;
+
+            let mut index_wtxn = index.write_txn()?;
+
+            let mut indexer = indexer::DocumentDeletion::new();
+            indexer.delete_documents_by_docids(documents_to_delete);
+            let document_changes = indexer.into_changes(&indexer_alloc, primary_key);
+            let embedders = index
+                .embedding_configs()
+                .embedding_configs(&index_wtxn)
+                .map_err(milli::Error::from)
+                .map_err(err)?;
+            let embedders = self.embedders(index_uid, embedders)?;
+            let indexer_config = self.index_mapper.indexer_config();
+            let pool = &indexer_config.thread_pool;
+
+            indexer::index(
+                &mut index_wtxn,
+                index,
+                pool,
+                indexer_config.grenad_parameters(),
+                &fields_ids_map,
+                new_fields_ids_map,
+                None, // document deletion never changes primary key
+                &document_changes,
+                embedders,
+                &|| must_stop_processing.get(),
+                &progress,
+                &EmbedderStats::default(),
+            )
+            .map_err(err)?;
+
+            index_wtxn.commit()?;
+
+            Ok(())
+        })?;
+        Ok(())
+    }
+}
+
+fn proxy_network(
+    runtime: &tokio::runtime::Handle,
+    url: &str,
+    network: &DbNetwork,
+) -> crate::Result<tokio::task::JoinHandle<()>> {
+    todo!()
+}
+
+fn accumulate(old_network: DbNetwork, new_network: Network) -> crate::Result<DbNetwork> {
+    let err = |err| Err(Error::from_milli(milli::Error::UserError(err), None));
+
+    let merged_local = match new_network.local {
+        Setting::Set(new_self) => Some(new_self),
+        Setting::Reset => None,
+        Setting::NotSet => old_network.local,
+    };
+
+    let merged_sharding = match new_network.sharding {
+        Setting::Set(new_sharding) => new_sharding,
+        Setting::Reset => false,
+        Setting::NotSet => old_network.sharding,
+    };
+
+    if merged_sharding && merged_local.is_none() {
+        return err(milli::UserError::NetworkShardingWithoutSelf);
+    }
+
+    let merged_remotes = match new_network.remotes {
+        Setting::Set(new_remotes) => {
+            let mut merged_remotes = BTreeMap::new();
+            for either_or_both in old_network
+                .remotes
+                .into_iter()
+                .merge_join_by(new_remotes.into_iter(), |left, right| left.0.cmp(&right.0))
+            {
+                match either_or_both {
+                    EitherOrBoth::Both((name, old), (_, Some(new))) => {
+                        let DbRemote {
+                            url: old_url,
+                            search_api_key: old_search_api_key,
+                            write_api_key: old_write_api_key,
+                        } = old;
+
+                        let Remote {
+                            url: new_url,
+                            search_api_key: new_search_api_key,
+                            write_api_key: new_write_api_key,
+                        } = new;
+
+                        let merged = DbRemote {
+                            url: match new_url {
+                                Setting::Set(new_url) => new_url,
+                                Setting::Reset => {
+                                    return err(milli::UserError::NetworkMissingUrl(name))
+                                }
+                                Setting::NotSet => old_url,
+                            },
+                            search_api_key: match new_search_api_key {
+                                Setting::Set(new_search_api_key) => Some(new_search_api_key),
+                                Setting::Reset => None,
+                                Setting::NotSet => old_search_api_key,
+                            },
+                            write_api_key: match new_write_api_key {
+                                Setting::Set(new_write_api_key) => Some(new_write_api_key),
+                                Setting::Reset => None,
+                                Setting::NotSet => old_write_api_key,
+                            },
+                        };
+                        merged_remotes.insert(name, merged);
+                    }
+                    EitherOrBoth::Both((_, _), (_, None)) | EitherOrBoth::Right((_, None)) => {}
+                    EitherOrBoth::Left((name, node)) => {
+                        merged_remotes.insert(name, node);
+                    }
+                    EitherOrBoth::Right((name, Some(node))) => {
+                        let Some(url) = node.url.set() else {
+                            return err(milli::UserError::NetworkMissingUrl(name));
+                        };
+                        let node = DbRemote {
+                            url,
+                            search_api_key: node.search_api_key.set(),
+                            write_api_key: node.write_api_key.set(),
+                        };
+                        merged_remotes.insert(name, node);
+                    }
+                }
+            }
+            merged_remotes
+        }
+        Setting::Reset => BTreeMap::new(),
+        Setting::NotSet => old_network.remotes,
+    };
+
+    Ok(DbNetwork { local: merged_local, remotes: merged_remotes, sharding: merged_sharding })
+}

crates/index-scheduler/src/scheduler/mod.rs

@@ -2,6 +2,7 @@ mod autobatcher;
 #[cfg(test)]
 mod autobatcher_test;
 mod create_batch;
+mod enterprise_edition;
 mod process_batch;
 mod process_dump_creation;
 mod process_export;

crates/index-scheduler/src/scheduler/process_batch.rs

@@ -135,6 +135,9 @@ impl IndexScheduler {
             Batch::Dump(task) => self
                 .process_dump_creation(progress, task)
                 .map(|tasks| (tasks, ProcessBatchInfo::default())),
+            Batch::NetworkTopologyChanges { tasks } => self
+                .process_network_changes(progress, tasks)
+                .map(|tasks| (tasks, ProcessBatchInfo::default())),
             Batch::IndexOperation { op, must_create_index } => {
                 let index_uid = op.index_uid().to_string();
                 let index = if must_create_index {

crates/index-scheduler/src/scheduler/process_export.rs

@@ -16,6 +16,7 @@ use meilisearch_types::milli::vector::parsed_vectors::{ExplicitVectors, VectorOr
 use meilisearch_types::milli::{self, obkv_to_json, Filter, InternalError};
 use meilisearch_types::settings::{self, SecretPolicy};
 use meilisearch_types::tasks::{DetailsExportIndexSettings, ExportIndexSettings};
+use roaring::RoaringBitmap;
 use serde::Deserialize;
 use ureq::{json, Response};
 
@@ -50,6 +51,7 @@ impl IndexScheduler {
         let agent = ureq::AgentBuilder::new().timeout(Duration::from_secs(5)).build();
         let must_stop_processing = self.scheduler.must_stop_processing.clone();
         for (i, (_pattern, uid, export_settings)) in indexes.iter().enumerate() {
+            let err = |err| Error::from_milli(err, Some(uid.to_string()));
             if must_stop_processing.get() {
                 return Err(Error::AbortedTask);
             }
@@ -61,104 +63,31 @@ impl IndexScheduler {
             ));
 
             let ExportIndexSettings { filter, override_settings } = export_settings;
+
             let index = self.index(uid)?;
             let index_rtxn = index.read_txn()?;
-            let bearer = api_key.map(|api_key| format!("Bearer {api_key}"));
-
-            // First, check if the index already exists
-            let url = format!("{base_url}/indexes/{uid}");
-            let response = retry(&must_stop_processing, || {
-                let mut request = agent.get(&url);
-                if let Some(bearer) = &bearer {
-                    request = request.set("Authorization", bearer);
-                }
-
-                request.send_bytes(Default::default()).map_err(into_backoff_error)
-            });
-            let index_exists = match response {
-                Ok(response) => response.status() == 200,
-                Err(Error::FromRemoteWhenExporting { code, .. }) if code == "index_not_found" => {
-                    false
-                }
-                Err(e) => return Err(e),
-            };
-
-            let primary_key = index
-                .primary_key(&index_rtxn)
-                .map_err(|e| Error::from_milli(e.into(), Some(uid.to_string())))?;
-
-            // Create the index
-            if !index_exists {
-                let url = format!("{base_url}/indexes");
-                retry(&must_stop_processing, || {
-                    let mut request = agent.post(&url);
-                    if let Some(bearer) = &bearer {
-                        request = request.set("Authorization", bearer);
-                    }
-                    let index_param = json!({ "uid": uid, "primaryKey": primary_key });
-                    request.send_json(&index_param).map_err(into_backoff_error)
-                })?;
-            }
-
-            // Patch the index primary key
-            if index_exists && *override_settings {
-                let url = format!("{base_url}/indexes/{uid}");
-                retry(&must_stop_processing, || {
-                    let mut request = agent.patch(&url);
-                    if let Some(bearer) = &bearer {
-                        request = request.set("Authorization", bearer);
-                    }
-                    let index_param = json!({ "primaryKey": primary_key });
-                    request.send_json(&index_param).map_err(into_backoff_error)
-                })?;
-            }
-
-            // Send the index settings
-            if !index_exists || *override_settings {
-                let mut settings =
-                    settings::settings(&index, &index_rtxn, SecretPolicy::RevealSecrets)
-                        .map_err(|e| Error::from_milli(e, Some(uid.to_string())))?;
-                // Remove the experimental chat setting if not enabled
-                if self.features().check_chat_completions("exporting chat settings").is_err() {
-                    settings.chat = Setting::NotSet;
-                }
-                // Retry logic for sending settings
-                let url = format!("{base_url}/indexes/{uid}/settings");
-                retry(&must_stop_processing, || {
-                    let mut request = agent.patch(&url);
-                    if let Some(bearer) = bearer.as_ref() {
-                        request = request.set("Authorization", bearer);
-                    }
-                    request.send_json(settings.clone()).map_err(into_backoff_error)
-                })?;
-            }
-
-            let filter = filter
-                .as_ref()
-                .map(Filter::from_json)
-                .transpose()
-                .map_err(|e| Error::from_milli(e, Some(uid.to_string())))?
-                .flatten();
-
-            let filter_universe = filter
-                .map(|f| f.evaluate(&index_rtxn, &index))
-                .transpose()
-                .map_err(|e| Error::from_milli(e, Some(uid.to_string())))?;
-            let whole_universe = index
-                .documents_ids(&index_rtxn)
-                .map_err(|e| Error::from_milli(e.into(), Some(uid.to_string())))?;
+            let filter = filter.as_ref().map(Filter::from_json).transpose().map_err(err)?.flatten();
+            let filter_universe =
+                filter.map(|f| f.evaluate(&index_rtxn, &index)).transpose().map_err(err)?;
+            let whole_universe =
+                index.documents_ids(&index_rtxn).map_err(milli::Error::from).map_err(err)?;
             let universe = filter_universe.unwrap_or(whole_universe);
-
-            let fields_ids_map = index.fields_ids_map(&index_rtxn)?;
-            let all_fields: Vec<_> = fields_ids_map.iter().map(|(id, _)| id).collect();
-
-            // We don't need to keep this one alive as we will
-            // spawn many threads to process the documents
-            drop(index_rtxn);
-
-            let total_documents = universe.len() as u32;
-            let (step, progress_step) = AtomicDocumentStep::new(total_documents);
-            progress.update_progress(progress_step);
+            let target = TargetInstance { base_url, api_key };
+            let ctx = ExportContext {
+                index: &index,
+                index_rtxn: &index_rtxn,
+                universe: &universe,
+                progress: &progress,
+                agent: &agent,
+                must_stop_processing: &must_stop_processing,
+            };
+            let options = ExportOptions {
+                index_uid: uid,
+                payload_size,
+                override_settings: *override_settings,
+                extra_headers: &Default::default(),
+            };
+            let total_documents = self.export_one_index(target, options, ctx)?;
 
             output.insert(
                 IndexUidPattern::new_unchecked(uid.clone()),
@@ -167,155 +96,217 @@ impl IndexScheduler {
                     matched_documents: Some(total_documents as u64),
                 },
             );
-
-            let limit = payload_size.map(|ps| ps.as_u64() as usize).unwrap_or(20 * 1024 * 1024); // defaults to 20 MiB
-            let documents_url = format!("{base_url}/indexes/{uid}/documents");
-
-            let results = request_threads()
-                .broadcast(|ctx| {
-                    let index_rtxn = index
-                        .read_txn()
-                        .map_err(|e| Error::from_milli(e.into(), Some(uid.to_string())))?;
-
-                    let mut buffer = Vec::new();
-                    let mut tmp_buffer = Vec::new();
-                    let mut compressed_buffer = Vec::new();
-                    for (i, docid) in universe.iter().enumerate() {
-                        if i % ctx.num_threads() != ctx.index() {
-                            continue;
-                        }
-
-                        let document = index
-                            .document(&index_rtxn, docid)
-                            .map_err(|e| Error::from_milli(e, Some(uid.to_string())))?;
-
-                        let mut document = obkv_to_json(&all_fields, &fields_ids_map, document)
-                            .map_err(|e| Error::from_milli(e, Some(uid.to_string())))?;
-
-                        // TODO definitely factorize this code
-                        'inject_vectors: {
-                            let embeddings = index
-                                .embeddings(&index_rtxn, docid)
-                                .map_err(|e| Error::from_milli(e, Some(uid.to_string())))?;
-
-                            if embeddings.is_empty() {
-                                break 'inject_vectors;
-                            }
-
-                            let vectors = document
-                                .entry(RESERVED_VECTORS_FIELD_NAME)
-                                .or_insert(serde_json::Value::Object(Default::default()));
-
-                            let serde_json::Value::Object(vectors) = vectors else {
-                                return Err(Error::from_milli(
-                                    milli::Error::UserError(
-                                        milli::UserError::InvalidVectorsMapType {
-                                            document_id: {
-                                                if let Ok(Some(Ok(index))) = index
-                                                    .external_id_of(
-                                                        &index_rtxn,
-                                                        std::iter::once(docid),
-                                                    )
-                                                    .map(|it| it.into_iter().next())
-                                                {
-                                                    index
-                                                } else {
-                                                    format!("internal docid={docid}")
-                                                }
-                                            },
-                                            value: vectors.clone(),
-                                        },
-                                    ),
-                                    Some(uid.to_string()),
-                                ));
-                            };
-
-                            for (
-                                embedder_name,
-                                EmbeddingsWithMetadata { embeddings, regenerate, has_fragments },
-                            ) in embeddings
-                            {
-                                let embeddings = ExplicitVectors {
-                                    embeddings: Some(
-                                        VectorOrArrayOfVectors::from_array_of_vectors(embeddings),
-                                    ),
-                                    regenerate: regenerate &&
-                                    // Meilisearch does not handle well dumps with fragments, because as the fragments
-                                    // are marked as user-provided,
-                                    // all embeddings would be regenerated on any settings change or document update.
-                                    // To prevent this, we mark embeddings has non regenerate in this case.
-                                    !has_fragments,
-                                };
-                                vectors.insert(
-                                    embedder_name,
-                                    serde_json::to_value(embeddings).unwrap(),
-                                );
-                            }
-                        }
-
-                        tmp_buffer.clear();
-                        serde_json::to_writer(&mut tmp_buffer, &document)
-                            .map_err(milli::InternalError::from)
-                            .map_err(|e| Error::from_milli(e.into(), Some(uid.to_string())))?;
-
-                        // Make sure we put at least one document in the buffer even
-                        // though we might go above the buffer limit before sending
-                        if !buffer.is_empty() && buffer.len() + tmp_buffer.len() > limit {
-                            // We compress the documents before sending them
-                            let mut encoder =
-                                GzEncoder::new(&mut compressed_buffer, Compression::default());
-                            encoder
-                                .write_all(&buffer)
-                                .map_err(|e| Error::from_milli(e.into(), Some(uid.clone())))?;
-                            encoder
-                                .finish()
-                                .map_err(|e| Error::from_milli(e.into(), Some(uid.clone())))?;
-
-                            retry(&must_stop_processing, || {
-                                let mut request = agent.post(&documents_url);
-                                request = request.set("Content-Type", "application/x-ndjson");
-                                request = request.set("Content-Encoding", "gzip");
-                                if let Some(bearer) = &bearer {
-                                    request = request.set("Authorization", bearer);
-                                }
-                                request.send_bytes(&compressed_buffer).map_err(into_backoff_error)
-                            })?;
-                            buffer.clear();
-                            compressed_buffer.clear();
-                        }
-                        buffer.extend_from_slice(&tmp_buffer);
-
-                        if i > 0 && i % 100 == 0 {
-                            step.fetch_add(100, atomic::Ordering::Relaxed);
-                        }
-                    }
-
-                    retry(&must_stop_processing, || {
-                        let mut request = agent.post(&documents_url);
-                        request = request.set("Content-Type", "application/x-ndjson");
-                        if let Some(bearer) = &bearer {
-                            request = request.set("Authorization", bearer);
-                        }
-                        request.send_bytes(&buffer).map_err(into_backoff_error)
-                    })?;
-
-                    Ok(())
-                })
-                .map_err(|e| {
-                    Error::from_milli(
-                        milli::Error::InternalError(InternalError::PanicInThreadPool(e)),
-                        Some(uid.to_string()),
-                    )
-                })?;
-            for result in results {
-                result?;
-            }
-
-            step.store(total_documents, atomic::Ordering::Relaxed);
         }
 
         Ok(output)
     }
+
+    pub(super) fn export_one_index(
+        &self,
+        target: TargetInstance<'_>,
+        options: ExportOptions<'_>,
+        ctx: ExportContext<'_>,
+    ) -> Result<u64, Error> {
+        let err = |err| Error::from_milli(err, Some(options.index_uid.to_string()));
+
+        let bearer = target.api_key.map(|api_key| format!("Bearer {api_key}"));
+        let url = format!(
+            "{base_url}/indexes/{index_uid}",
+            base_url = target.base_url,
+            index_uid = options.index_uid
+        );
+        let response = retry(ctx.must_stop_processing, || {
+            let mut request = ctx.agent.get(&url);
+            if let Some(bearer) = &bearer {
+                request = request.set("Authorization", bearer);
+            }
+
+            request.send_bytes(Default::default()).map_err(into_backoff_error)
+        });
+        let index_exists = match response {
+            Ok(response) => response.status() == 200,
+            Err(Error::FromRemoteWhenExporting { code, .. }) if code == "index_not_found" => false,
+            Err(e) => return Err(e),
+        };
+        let primary_key =
+            ctx.index.primary_key(&ctx.index_rtxn).map_err(milli::Error::from).map_err(err)?;
+        if !index_exists {
+            let url = format!("{base_url}/indexes", base_url = target.base_url);
+            retry(ctx.must_stop_processing, || {
+                let mut request = ctx.agent.post(&url);
+                if let Some(bearer) = &bearer {
+                    request = request.set("Authorization", bearer);
+                }
+                let index_param = json!({ "uid": options.index_uid, "primaryKey": primary_key });
+                request.send_json(&index_param).map_err(into_backoff_error)
+            })?;
+        }
+        if index_exists && options.override_settings {
+            retry(ctx.must_stop_processing, || {
+                let mut request = ctx.agent.patch(&url);
+                if let Some(bearer) = &bearer {
+                    request = request.set("Authorization", bearer);
+                }
+                let index_param = json!({ "primaryKey": primary_key });
+                request.send_json(&index_param).map_err(into_backoff_error)
+            })?;
+        }
+        if !index_exists || options.override_settings {
+            let mut settings =
+                settings::settings(&ctx.index, &ctx.index_rtxn, SecretPolicy::RevealSecrets)
+                    .map_err(err)?;
+            // Remove the experimental chat setting if not enabled
+            if self.features().check_chat_completions("exporting chat settings").is_err() {
+                settings.chat = Setting::NotSet;
+            }
+            // Retry logic for sending settings
+            let url = format!(
+                "{base_url}/indexes/{index_uid}/settings",
+                base_url = target.base_url,
+                index_uid = options.index_uid
+            );
+            retry(ctx.must_stop_processing, || {
+                let mut request = ctx.agent.patch(&url);
+                if let Some(bearer) = bearer.as_ref() {
+                    request = request.set("Authorization", bearer);
+                }
+                request.send_json(settings.clone()).map_err(into_backoff_error)
+            })?;
+        }
+
+        let fields_ids_map = ctx.index.fields_ids_map(&ctx.index_rtxn)?;
+        let all_fields: Vec<_> = fields_ids_map.iter().map(|(id, _)| id).collect();
+        let total_documents = ctx.universe.len() as u32;
+        let (step, progress_step) = AtomicDocumentStep::new(total_documents);
+        ctx.progress.update_progress(progress_step);
+
+        let limit = options.payload_size.map(|ps| ps.as_u64() as usize).unwrap_or(20 * 1024 * 1024);
+        let documents_url = format!(
+            "{base_url}/indexes/{index_uid}/documents",
+            base_url = target.base_url,
+            index_uid = options.index_uid
+        );
+        let results = request_threads()
+            .broadcast(|broadcast| {
+                let index_rtxn = ctx.index.read_txn().map_err(milli::Error::from).map_err(err)?;
+
+                let mut buffer = Vec::new();
+                let mut tmp_buffer = Vec::new();
+                let mut compressed_buffer = Vec::new();
+                for (i, docid) in ctx.universe.iter().enumerate() {
+                    if i % broadcast.num_threads() != broadcast.index() {
+                        continue;
+                    }
+
+                    let document = ctx.index.document(&index_rtxn, docid).map_err(err)?;
+
+                    let mut document =
+                        obkv_to_json(&all_fields, &fields_ids_map, document).map_err(err)?;
+
+                    // TODO definitely factorize this code
+                    'inject_vectors: {
+                        let embeddings = ctx.index.embeddings(&index_rtxn, docid).map_err(err)?;
+
+                        if embeddings.is_empty() {
+                            break 'inject_vectors;
+                        }
+
+                        let vectors = document
+                            .entry(RESERVED_VECTORS_FIELD_NAME)
+                            .or_insert(serde_json::Value::Object(Default::default()));
+
+                        let serde_json::Value::Object(vectors) = vectors else {
+                            return Err(err(milli::Error::UserError(
+                                milli::UserError::InvalidVectorsMapType {
+                                    document_id: {
+                                        if let Ok(Some(Ok(index))) = ctx
+                                            .index
+                                            .external_id_of(&index_rtxn, std::iter::once(docid))
+                                            .map(|it| it.into_iter().next())
+                                        {
+                                            index
+                                        } else {
+                                            format!("internal docid={docid}")
+                                        }
+                                    },
+                                    value: vectors.clone(),
+                                },
+                            )));
+                        };
+
+                        for (
+                            embedder_name,
+                            EmbeddingsWithMetadata { embeddings, regenerate, has_fragments },
+                        ) in embeddings
+                        {
+                            let embeddings = ExplicitVectors {
+                                embeddings: Some(VectorOrArrayOfVectors::from_array_of_vectors(
+                                    embeddings,
+                                )),
+                                regenerate: regenerate &&
+                                // Meilisearch does not handle well dumps with fragments, because as the fragments
+                                // are marked as user-provided,
+                                // all embeddings would be regenerated on any settings change or document update.
+                                // To prevent this, we mark embeddings has non regenerate in this case.
+                                !has_fragments,
+                            };
+                            vectors
+                                .insert(embedder_name, serde_json::to_value(embeddings).unwrap());
+                        }
+                    }
+
+                    tmp_buffer.clear();
+                    serde_json::to_writer(&mut tmp_buffer, &document)
+                        .map_err(milli::InternalError::from)
+                        .map_err(milli::Error::from)
+                        .map_err(err)?;
+
+                    // Make sure we put at least one document in the buffer even
+                    // though we might go above the buffer limit before sending
+                    if !buffer.is_empty() && buffer.len() + tmp_buffer.len() > limit {
+                        // We compress the documents before sending them
+                        let mut encoder =
+                            GzEncoder::new(&mut compressed_buffer, Compression::default());
+                        encoder.write_all(&buffer).map_err(milli::Error::from).map_err(err)?;
+                        encoder.finish().map_err(milli::Error::from).map_err(err)?;
+
+                        retry(ctx.must_stop_processing, || {
+                            let mut request = ctx.agent.post(&documents_url);
+                            request = request.set("Content-Type", "application/x-ndjson");
+                            request = request.set("Content-Encoding", "gzip");
+                            if let Some(bearer) = &bearer {
+                                request = request.set("Authorization", bearer);
+                            }
+                            request.send_bytes(&compressed_buffer).map_err(into_backoff_error)
+                        })?;
+                        buffer.clear();
+                        compressed_buffer.clear();
+                    }
+                    buffer.extend_from_slice(&tmp_buffer);
+
+                    if i > 0 && i % 100 == 0 {
+                        step.fetch_add(100, atomic::Ordering::Relaxed);
+                    }
+                }
+
+                retry(ctx.must_stop_processing, || {
+                    let mut request = ctx.agent.post(&documents_url);
+                    request = request.set("Content-Type", "application/x-ndjson");
+                    if let Some(bearer) = &bearer {
+                        request = request.set("Authorization", bearer);
+                    }
+                    request.send_bytes(&buffer).map_err(into_backoff_error)
+                })?;
+
+                Ok(())
+            })
+            .map_err(|e| err(milli::Error::InternalError(InternalError::PanicInThreadPool(e))))?;
+        for result in results {
+            result?;
+        }
+        step.store(total_documents, atomic::Ordering::Relaxed);
+        Ok(total_documents as u64)
+    }
 }
 
 fn retry<F>(must_stop_processing: &MustStopProcessing, send_request: F) -> Result<ureq::Response>
@@ -374,4 +365,27 @@ fn ureq_error_into_error(error: ureq::Error) -> Error {
     }
 }
 
+// export_one_index arguments
+pub(super) struct TargetInstance<'a> {
+    pub(super) base_url: &'a str,
+    pub(super) api_key: Option<&'a str>,
+}
+
+pub(super) struct ExportOptions<'a> {
+    pub(super) index_uid: &'a str,
+    pub(super) payload_size: Option<&'a Byte>,
+    pub(super) override_settings: bool,
+    pub(super) extra_headers: &'a hashbrown::HashMap<String, String>,
+}
+
+pub(super) struct ExportContext<'a> {
+    pub(super) index: &'a meilisearch_types::milli::Index,
+    pub(super) index_rtxn: &'a milli::heed::RoTxn<'a>,
+    pub(super) universe: &'a RoaringBitmap,
+    pub(super) progress: &'a Progress,
+    pub(super) agent: &'a ureq::Agent,
+    pub(super) must_stop_processing: &'a MustStopProcessing,
+}
+
+// progress related
 enum ExportIndex {}

crates/index-scheduler/src/scheduler/process_index_operation.rs

@@ -97,7 +97,7 @@ impl IndexScheduler {
                     .embedding_configs()
                     .embedding_configs(index_wtxn)
                     .map_err(|e| Error::from_milli(e.into(), Some(index_uid.clone())))?;
-                let embedders = self.embedders(index_uid.clone(), embedders)?;
+                let embedders = self.embedders(&index_uid, embedders)?;
                 for operation in operations {
                     match operation {
                         DocumentOperation::Replace(_content_uuid) => {
@@ -284,7 +284,7 @@ impl IndexScheduler {
                         .embedding_configs()
                         .embedding_configs(index_wtxn)
                         .map_err(|err| Error::from_milli(err.into(), Some(index_uid.clone())))?;
-                    let embedders = self.embedders(index_uid.clone(), embedders)?;
+                    let embedders = self.embedders(&index_uid, embedders)?;
 
                     progress.update_progress(DocumentEditionProgress::Indexing);
                     congestion = Some(
@@ -434,7 +434,7 @@ impl IndexScheduler {
                         .embedding_configs()
                         .embedding_configs(index_wtxn)
                         .map_err(|err| Error::from_milli(err.into(), Some(index_uid.clone())))?;
-                    let embedders = self.embedders(index_uid.clone(), embedders)?;
+                    let embedders = self.embedders(&index_uid, embedders)?;
 
                     progress.update_progress(DocumentDeletionProgress::Indexing);
                     congestion = Some(

crates/index-scheduler/src/scheduler/test.rs

@@ -722,7 +722,7 @@ fn basic_get_stats() {
     let kind = index_creation_task("whalo", "fish");
     let _task = index_scheduler.register(kind, None, false).unwrap();
 
-    snapshot!(json_string!(index_scheduler.get_stats().unwrap()), @r#"
+    snapshot!(json_string!(index_scheduler.get_stats().unwrap()), @r###"
     {
       "indexes": {
         "catto": 1,
@@ -746,6 +746,7 @@ fn basic_get_stats() {
         "indexDeletion": 0,
         "indexSwap": 0,
         "indexUpdate": 0,
+        "networkTopologyChange": 0,
         "settingsUpdate": 0,
         "snapshotCreation": 0,
         "taskCancelation": 0,
@@ -753,7 +754,7 @@ fn basic_get_stats() {
         "upgradeDatabase": 0
       }
     }
-    "#);
+    "###);
 
     handle.advance_till([Start, BatchCreated]);
     snapshot!(json_string!(index_scheduler.get_stats().unwrap()), @r#"

crates/index-scheduler/src/scheduler/test_embedders.rs

@@ -121,7 +121,7 @@ fn import_vectors() {
         insta::assert_json_snapshot!(simple_hf_config.embedder_options);
         let simple_hf_name = name.clone();
 
-        let configs = index_scheduler.embedders("doggos".to_string(), configs).unwrap();
+        let configs = index_scheduler.embedders("doggos", configs).unwrap();
         let hf_runtime = configs.get(&simple_hf_name).unwrap();
         let hf_embedder = &hf_runtime.embedder;
         let beagle_embed = hf_embedder

crates/index-scheduler/src/test_utils.rs

@@ -126,7 +126,7 @@ impl IndexScheduler {
         std::fs::create_dir_all(&options.auth_path).unwrap();
         let auth_env = open_auth_store_env(&options.auth_path).unwrap();
         let index_scheduler =
-            Self::new(options, auth_env, version, sender, planned_failures).unwrap();
+            Self::new(options, auth_env, version, None, sender, planned_failures).unwrap();
 
         // To be 100% consistent between all test we're going to start the scheduler right now
         // and ensure it's in the expected starting state.

crates/index-scheduler/src/utils.rs

@@ -285,6 +285,7 @@ pub fn swap_index_uid_in_task(task: &mut Task, swap: (&str, &str)) {
         | K::DumpCreation { .. }
         | K::Export { .. }
         | K::UpgradeDatabase { .. }
+        | K::NetworkTopologyChange { .. }
         | K::SnapshotCreation => (),
     };
     if let Some(Details::IndexSwap { swaps }) = &mut task.details {
@@ -618,6 +619,9 @@ impl crate::IndexScheduler {
                     Details::UpgradeDatabase { from: _, to: _ } => {
                         assert_eq!(kind.as_kind(), Kind::UpgradeDatabase);
                     }
+                    Details::NetworkTopologyChange { .. } => {
+                        assert_eq!(kind.as_kind(), Kind::NetworkTopologyChange);
+                    }
                 }
             }
 

crates/meilisearch-types/src/enterprise_edition/network.rs

@@ -5,31 +5,85 @@
 
 use std::collections::BTreeMap;
 
-use milli::update::new::indexer::enterprise_edition::sharding::Shards;
+use deserr::Deserr;
+use milli::update::new::indexer::enterprise_edition::sharding::{Shard, Shards};
+use milli::update::Setting;
 use serde::{Deserialize, Serialize};
+use utoipa::ToSchema;
+
+use crate::deserr::DeserrJsonError;
+use crate::error::deserr_codes::{
+    InvalidNetworkRemotes, InvalidNetworkSearchApiKey, InvalidNetworkSelf, InvalidNetworkSharding,
+    InvalidNetworkUrl, InvalidNetworkWriteApiKey,
+};
+
+#[derive(Clone, Debug, Deserr, ToSchema, Serialize, Deserialize, PartialEq, Eq)]
+#[deserr(error = DeserrJsonError, rename_all = camelCase, deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+#[schema(rename_all = "camelCase")]
+pub struct Network {
+    #[schema(value_type = Option<BTreeMap<String, Remote>>, example = json!("http://localhost:7700"))]
+    #[deserr(default, error = DeserrJsonError<InvalidNetworkRemotes>)]
+    #[serde(default)]
+    pub remotes: Setting<BTreeMap<String, Option<Remote>>>,
+    #[schema(value_type = Option<String>, example = json!("ms-00"), rename = "self")]
+    #[serde(default, rename = "self")]
+    #[deserr(default, rename = "self", error = DeserrJsonError<InvalidNetworkSelf>)]
+    pub local: Setting<String>,
+    #[schema(value_type = Option<bool>, example = json!(true))]
+    #[serde(default)]
+    #[deserr(default, error = DeserrJsonError<InvalidNetworkSharding>)]
+    pub sharding: Setting<bool>,
+}
+
+#[derive(Clone, Debug, Deserr, ToSchema, Serialize, Deserialize, PartialEq, Eq)]
+#[deserr(error = DeserrJsonError<InvalidNetworkRemotes>, rename_all = camelCase, deny_unknown_fields)]
+#[serde(rename_all = "camelCase")]
+#[schema(rename_all = "camelCase")]
+pub struct Remote {
+    #[schema(value_type = Option<String>, example = json!({
+        "ms-0": Remote { url: Setting::Set("http://localhost:7700".into()), search_api_key: Setting::Reset, write_api_key: Setting::Reset },
+        "ms-1": Remote { url: Setting::Set("http://localhost:7701".into()), search_api_key: Setting::Set("foo".into()), write_api_key: Setting::Set("bar".into()) },
+        "ms-2": Remote { url: Setting::Set("http://localhost:7702".into()), search_api_key: Setting::Set("bar".into()), write_api_key: Setting::Set("foo".into()) },
+    }))]
+    #[deserr(default, error = DeserrJsonError<InvalidNetworkUrl>)]
+    #[serde(default)]
+    pub url: Setting<String>,
+    #[schema(value_type = Option<String>, example = json!("XWnBI8QHUc-4IlqbKPLUDuhftNq19mQtjc6JvmivzJU"))]
+    #[deserr(default, error = DeserrJsonError<InvalidNetworkSearchApiKey>)]
+    #[serde(default)]
+    pub search_api_key: Setting<String>,
+    #[schema(value_type = Option<String>, example = json!("XWnBI8QHUc-4IlqbKPLUDuhftNq19mQtjc6JvmivzJU"))]
+    #[deserr(default, error = DeserrJsonError<InvalidNetworkWriteApiKey>)]
+    #[serde(default)]
+    pub write_api_key: Setting<String>,
+}
 
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq, Default)]
 #[serde(rename_all = "camelCase")]
-pub struct Network {
+pub struct DbNetwork {
     #[serde(default, rename = "self")]
     pub local: Option<String>,
     #[serde(default)]
-    pub remotes: BTreeMap<String, Remote>,
+    pub remotes: BTreeMap<String, DbRemote>,
     #[serde(default)]
     pub sharding: bool,
 }
 
-impl Network {
+impl DbNetwork {
     pub fn shards(&self) -> Option<Shards> {
         if self.sharding {
-            let this = self.local.as_deref().expect("Inconsistent `sharding` and `self`");
-            let others = self
-                .remotes
-                .keys()
-                .filter(|name| name.as_str() != this)
-                .map(|name| name.to_owned())
-                .collect();
-            Some(Shards { own: vec![this.to_owned()], others })
+            let this = self.local.as_deref();
+
+            Some(Shards(
+                self.remotes
+                    .keys()
+                    .map(|name| Shard {
+                        is_own: Some(name.as_str()) == this,
+                        name: name.to_owned(),
+                    })
+                    .collect(),
+            ))
         } else {
             None
         }
@@ -38,7 +92,7 @@ impl Network {
 
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq)]
 #[serde(rename_all = "camelCase")]
-pub struct Remote {
+pub struct DbRemote {
     pub url: String,
     #[serde(default)]
     pub search_api_key: Option<String>,

crates/meilisearch-types/src/error.rs

@@ -529,6 +529,8 @@ impl ErrorCode for milli::Error {
                     | UserError::DocumentEditionCompilationError(_) => {
                         Code::EditDocumentsByFunctionError
                     }
+                    UserError::NetworkShardingWithoutSelf => Code::InvalidNetworkSharding,
+                    UserError::NetworkMissingUrl(_) => Code::MissingNetworkUrl,
                     UserError::CelluliteError(err) => match err {
                         cellulite::Error::BuildCanceled
                         | cellulite::Error::VersionMismatchOnBuild(_)

crates/meilisearch-types/src/task_view.rs

@@ -7,6 +7,7 @@ use time::{Duration, OffsetDateTime};
 use utoipa::ToSchema;
 
 use crate::batches::BatchId;
+use crate::enterprise_edition::network::Network;
 use crate::error::ResponseError;
 use crate::settings::{Settings, Unchecked};
 use crate::tasks::{
@@ -142,6 +143,9 @@ pub struct DetailsView {
     pub old_index_uid: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub new_index_uid: Option<String>,
+    // network
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub network: Option<Network>,
 }
 
 impl DetailsView {
@@ -314,6 +318,10 @@ impl DetailsView {
                 // We should never be able to batch multiple renames at the same time.
                 (Some(left), Some(_right)) => Some(left),
             },
+            network: match (&self.network, &other.network) {
+                (None, None) => None,
+                (_, Some(network)) | (Some(network), None) => Some(network.clone()),
+            },
         }
     }
 }
@@ -415,6 +423,9 @@ impl From<Details> for DetailsView {
                 upgrade_to: Some(format!("v{}.{}.{}", to.0, to.1, to.2)),
                 ..Default::default()
             },
+            Details::NetworkTopologyChange { network: new_network } => {
+                DetailsView { network: new_network, ..Default::default() }
+            }
         }
     }
 }

crates/meilisearch-types/src/tasks.rs

@@ -15,6 +15,7 @@ use utoipa::{schema, ToSchema};
 use uuid::Uuid;
 
 use crate::batches::BatchId;
+use crate::enterprise_edition::network::Network;
 use crate::error::ResponseError;
 use crate::index_uid_pattern::IndexUidPattern;
 use crate::keys::Key;
@@ -58,6 +59,7 @@ impl Task {
             | TaskDeletion { .. }
             | Export { .. }
             | UpgradeDatabase { .. }
+            | NetworkTopologyChange { .. }
             | IndexSwap { .. } => None,
             DocumentAdditionOrUpdate { index_uid, .. }
             | DocumentEdition { index_uid, .. }
@@ -94,7 +96,8 @@ impl Task {
             | KindWithContent::DumpCreation { .. }
             | KindWithContent::SnapshotCreation
             | KindWithContent::Export { .. }
-            | KindWithContent::UpgradeDatabase { .. } => None,
+            | KindWithContent::UpgradeDatabase { .. }
+            | KindWithContent::NetworkTopologyChange { .. } => None,
         }
     }
 }
@@ -170,6 +173,10 @@ pub enum KindWithContent {
     UpgradeDatabase {
         from: (u32, u32, u32),
     },
+    NetworkTopologyChange {
+        network: Option<Network>,
+        origin: Option<Origin>,
+    },
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
@@ -206,6 +213,7 @@ impl KindWithContent {
             KindWithContent::SnapshotCreation => Kind::SnapshotCreation,
             KindWithContent::Export { .. } => Kind::Export,
             KindWithContent::UpgradeDatabase { .. } => Kind::UpgradeDatabase,
+            KindWithContent::NetworkTopologyChange { .. } => Kind::NetworkTopologyChange,
         }
     }
 
@@ -218,6 +226,7 @@ impl KindWithContent {
             | TaskCancelation { .. }
             | TaskDeletion { .. }
             | Export { .. }
+            | NetworkTopologyChange { .. }
             | UpgradeDatabase { .. } => vec![],
             DocumentAdditionOrUpdate { index_uid, .. }
             | DocumentEdition { index_uid, .. }
@@ -325,6 +334,9 @@ impl KindWithContent {
                     versioning::VERSION_PATCH,
                 ),
             }),
+            KindWithContent::NetworkTopologyChange { network: new_network, origin: _ } => {
+                Some(Details::NetworkTopologyChange { network: new_network.clone() })
+            }
         }
     }
 
@@ -407,6 +419,9 @@ impl KindWithContent {
                     versioning::VERSION_PATCH,
                 ),
             }),
+            KindWithContent::NetworkTopologyChange { network: new_network, origin: _s } => {
+                Some(Details::NetworkTopologyChange { network: new_network.clone() })
+            }
         }
     }
 }
@@ -469,6 +484,9 @@ impl From<&KindWithContent> for Option<Details> {
                     versioning::VERSION_PATCH,
                 ),
             }),
+            KindWithContent::NetworkTopologyChange { network: new_network, origin: _ } => {
+                Some(Details::NetworkTopologyChange { network: new_network.clone() })
+            }
         }
     }
 }
@@ -579,6 +597,7 @@ pub enum Kind {
     SnapshotCreation,
     Export,
     UpgradeDatabase,
+    NetworkTopologyChange,
 }
 
 impl Kind {
@@ -597,7 +616,8 @@ impl Kind {
             | Kind::DumpCreation
             | Kind::Export
             | Kind::UpgradeDatabase
-            | Kind::SnapshotCreation => false,
+            | Kind::SnapshotCreation
+            | Kind::NetworkTopologyChange => false,
         }
     }
 }
@@ -618,6 +638,7 @@ impl Display for Kind {
             Kind::SnapshotCreation => write!(f, "snapshotCreation"),
             Kind::Export => write!(f, "export"),
             Kind::UpgradeDatabase => write!(f, "upgradeDatabase"),
+            Kind::NetworkTopologyChange => write!(f, "networkTopologyChange"),
         }
     }
 }
@@ -653,6 +674,8 @@ impl FromStr for Kind {
             Ok(Kind::Export)
         } else if kind.eq_ignore_ascii_case("upgradeDatabase") {
             Ok(Kind::UpgradeDatabase)
+        } else if kind.eq_ignore_ascii_case("networkTopologyChange") {
+            Ok(Kind::NetworkTopologyChange)
         } else {
             Err(ParseTaskKindError(kind.to_owned()))
         }
@@ -738,6 +761,9 @@ pub enum Details {
         from: (u32, u32, u32),
         to: (u32, u32, u32),
     },
+    NetworkTopologyChange {
+        network: Option<Network>,
+    },
 }
 
 #[derive(Debug, PartialEq, Clone, Serialize, Deserialize, ToSchema)]
@@ -805,6 +831,7 @@ impl Details {
             | Self::Dump { .. }
             | Self::Export { .. }
             | Self::UpgradeDatabase { .. }
+            | Self::NetworkTopologyChange { .. }
             | Self::IndexSwap { .. } => (),
         }
 

crates/meilisearch/src/lib.rs

@@ -216,7 +216,10 @@ enum OnFailure {
     KeepDb,
 }
 
-pub fn setup_meilisearch(opt: &Opt) -> anyhow::Result<(Arc<IndexScheduler>, Arc<AuthController>)> {
+pub fn setup_meilisearch(
+    opt: &Opt,
+    handle: tokio::runtime::Handle,
+) -> anyhow::Result<(Arc<IndexScheduler>, Arc<AuthController>)> {
     let index_scheduler_opt = IndexSchedulerOptions {
         version_file_path: opt.db_path.join(VERSION_FILE_NAME),
         auth_path: opt.db_path.join("auth"),
@@ -256,6 +259,7 @@ pub fn setup_meilisearch(opt: &Opt) -> anyhow::Result<(Arc<IndexScheduler>, Arc<
                     index_scheduler_opt,
                     OnFailure::RemoveDb,
                     binary_version, // the db is empty
+                    handle,
                 )?,
                 Err(e) => {
                     std::fs::remove_dir_all(&opt.db_path)?;
@@ -273,7 +277,7 @@ pub fn setup_meilisearch(opt: &Opt) -> anyhow::Result<(Arc<IndexScheduler>, Arc<
             bail!("snapshot doesn't exist at {}", snapshot_path.display())
         // the snapshot and the db exist, and we can ignore the snapshot because of the ignore_snapshot_if_db_exists flag
         } else {
-            open_or_create_database(opt, index_scheduler_opt, empty_db, binary_version)?
+            open_or_create_database(opt, index_scheduler_opt, empty_db, binary_version, handle)?
         }
     } else if let Some(ref path) = opt.import_dump {
         let src_path_exists = path.exists();
@@ -284,6 +288,7 @@ pub fn setup_meilisearch(opt: &Opt) -> anyhow::Result<(Arc<IndexScheduler>, Arc<
                 index_scheduler_opt,
                 OnFailure::RemoveDb,
                 binary_version, // the db is empty
+                handle,
             )?;
             match import_dump(&opt.db_path, path, &mut index_scheduler, &mut auth_controller) {
                 Ok(()) => (index_scheduler, auth_controller),
@@ -304,10 +309,10 @@ pub fn setup_meilisearch(opt: &Opt) -> anyhow::Result<(Arc<IndexScheduler>, Arc<
         // the dump and the db exist and we can ignore the dump because of the ignore_dump_if_db_exists flag
         // or, the dump is missing but we can ignore that because of the ignore_missing_dump flag
         } else {
-            open_or_create_database(opt, index_scheduler_opt, empty_db, binary_version)?
+            open_or_create_database(opt, index_scheduler_opt, empty_db, binary_version, handle)?
         }
     } else {
-        open_or_create_database(opt, index_scheduler_opt, empty_db, binary_version)?
+        open_or_create_database(opt, index_scheduler_opt, empty_db, binary_version, handle)?
     };
 
     // We create a loop in a thread that registers snapshotCreation tasks
@@ -338,6 +343,7 @@ fn open_or_create_database_unchecked(
     index_scheduler_opt: IndexSchedulerOptions,
     on_failure: OnFailure,
     version: (u32, u32, u32),
+    handle: tokio::runtime::Handle,
 ) -> anyhow::Result<(IndexScheduler, AuthController)> {
     // we don't want to create anything in the data.ms yet, thus we
     // wrap our two builders in a closure that'll be executed later.
@@ -345,7 +351,7 @@ fn open_or_create_database_unchecked(
     let auth_env = open_auth_store_env(&index_scheduler_opt.auth_path).unwrap();
     let auth_controller = AuthController::new(auth_env.clone(), &opt.master_key);
     let index_scheduler_builder = || -> anyhow::Result<_> {
-        Ok(IndexScheduler::new(index_scheduler_opt, auth_env, version)?)
+        Ok(IndexScheduler::new(index_scheduler_opt, auth_env, version, Some(handle))?)
     };
 
     match (
@@ -452,6 +458,7 @@ fn open_or_create_database(
     index_scheduler_opt: IndexSchedulerOptions,
     empty_db: bool,
     binary_version: (u32, u32, u32),
+    handle: tokio::runtime::Handle,
 ) -> anyhow::Result<(IndexScheduler, AuthController)> {
     let version = if !empty_db {
         check_version(opt, &index_scheduler_opt, binary_version)?
@@ -459,7 +466,7 @@ fn open_or_create_database(
         binary_version
     };
 
-    open_or_create_database_unchecked(opt, index_scheduler_opt, OnFailure::KeepDb, version)
+    open_or_create_database_unchecked(opt, index_scheduler_opt, OnFailure::KeepDb, version, handle)
 }
 
 fn import_dump(
@@ -584,7 +591,7 @@ fn import_dump(
             let reader = DocumentsBatchReader::from_reader(reader)?;
 
             let embedder_configs = index.embedding_configs().embedding_configs(&wtxn)?;
-            let embedders = index_scheduler.embedders(uid.to_string(), embedder_configs)?;
+            let embedders = index_scheduler.embedders(&uid, embedder_configs)?;
 
             let builder = milli::update::IndexDocuments::new(
                 &mut wtxn,
@@ -612,7 +619,7 @@ fn import_dump(
 
             let mut indexer = indexer::DocumentOperation::new();
             let embedders = index.embedding_configs().embedding_configs(&rtxn)?;
-            let embedders = index_scheduler.embedders(uid.clone(), embedders)?;
+            let embedders = index_scheduler.embedders(&uid, embedders)?;
 
             let mmap = unsafe { memmap2::Mmap::map(index_reader.documents_file())? };
 

crates/meilisearch/src/main.rs

@@ -76,7 +76,10 @@ fn on_panic(info: &std::panic::PanicHookInfo) {
 
 #[actix_web::main]
 async fn main() -> anyhow::Result<()> {
-    try_main().await.inspect_err(|error| {
+    // won't panic inside of tokio::main
+    let runtime = tokio::runtime::Handle::current();
+
+    try_main(runtime).await.inspect_err(|error| {
         tracing::error!(%error);
         let mut current = error.source();
         let mut depth = 0;
@@ -88,7 +91,7 @@ async fn main() -> anyhow::Result<()> {
     })
 }
 
-async fn try_main() -> anyhow::Result<()> {
+async fn try_main(runtime: tokio::runtime::Handle) -> anyhow::Result<()> {
     let (opt, config_read_from) = Opt::try_build()?;
 
     std::panic::set_hook(Box::new(on_panic));
@@ -122,7 +125,7 @@ async fn try_main() -> anyhow::Result<()> {
         _ => (),
     }
 
-    let (index_scheduler, auth_controller) = setup_meilisearch(&opt)?;
+    let (index_scheduler, auth_controller) = setup_meilisearch(&opt, runtime)?;
 
     let analytics =
         analytics::Analytics::new(&opt, index_scheduler.clone(), auth_controller.clone()).await;

crates/meilisearch/src/routes/chats/chat_completions.rs

@@ -282,8 +282,7 @@ async fn process_search_request(
     if let Some(search_rules) = auth_filter.get_index_search_rules(&index_uid) {
         add_search_rules(&mut query.filter, search_rules);
     }
-    let search_kind =
-        search_kind(&query, index_scheduler.get_ref(), index_uid.to_string(), &index)?;
+    let search_kind = search_kind(&query, index_scheduler.get_ref(), &index_uid, &index)?;
 
     let permit = search_queue.try_get_search_permit().await?;
     let features = index_scheduler.features();
@@ -300,7 +299,7 @@ async fn process_search_request(
         let (search, _is_finite_pagination, _max_total_hits, _offset) =
             prepare_search(&index_cloned, &rtxn, &query, &search_kind, time_budget, features)?;
 
-        match search_from_kind(index_uid, search_kind, search) {
+        match search_from_kind(&index_uid, search_kind, search) {
             Ok((search_results, _)) => Ok((rtxn, Ok(search_results))),
             Err(MeilisearchHttpError::Milli {
                 error: meilisearch_types::milli::Error::UserError(user_error),

crates/meilisearch/src/routes/indexes/documents.rs

@@ -45,7 +45,7 @@ use crate::extractors::authentication::policies::*;
 use crate::extractors::authentication::GuardedData;
 use crate::extractors::payload::Payload;
 use crate::extractors::sequential_extractor::SeqHandler;
-use crate::routes::indexes::enterprise_edition::proxy::{proxy, Body};
+use crate::routes::indexes::enterprise_edition::proxy::{check_leader, proxy, Body};
 use crate::routes::indexes::search::fix_sort_query_parameters;
 use crate::routes::{
     get_task_id, is_dry_run, PaginationView, SummarizedTaskView, PAGINATION_DEFAULT_LIMIT,
@@ -340,6 +340,7 @@ pub async fn delete_document(
     let DocumentParam { index_uid, document_id } = path.into_inner();
     let index_uid = IndexUid::try_from(index_uid)?;
     let network = index_scheduler.network();
+    let origin = check_leader(&req, &network)?;
 
     analytics.publish(
         DocumentsDeletionAggregator {
@@ -363,7 +364,7 @@ pub async fn delete_document(
     };
 
     if network.sharding && !dry_run {
-        proxy(&index_scheduler, &index_uid, &req, network, Body::none(), &task).await?;
+        proxy(&index_scheduler, &index_uid, &req, origin, network, Body::none(), &task).await?;
     }
 
     let task: SummarizedTaskView = task.into();
@@ -946,6 +947,7 @@ async fn document_addition(
 ) -> Result<SummarizedTaskView, MeilisearchHttpError> {
     let mime_type = extract_mime_type(req)?;
     let network = index_scheduler.network();
+    let origin = check_leader(&req, &network)?;
 
     let format = match (
         mime_type.as_ref().map(|m| (m.type_().as_str(), m.subtype().as_str())),
@@ -1081,6 +1083,7 @@ async fn document_addition(
                 &index_scheduler,
                 &index_uid,
                 req,
+                origin,
                 network,
                 Body::with_ndjson_payload(file),
                 &task,
@@ -1168,6 +1171,7 @@ pub async fn delete_documents_batch(
     debug!(parameters = ?body, "Delete documents by batch");
     let index_uid = IndexUid::try_from(index_uid.into_inner())?;
     let network = index_scheduler.network();
+    let origin = check_leader(&req, &network)?;
 
     analytics.publish(
         DocumentsDeletionAggregator {
@@ -1194,7 +1198,8 @@ pub async fn delete_documents_batch(
     };
 
     if network.sharding && !dry_run {
-        proxy(&index_scheduler, &index_uid, &req, network, Body::Inline(body), &task).await?;
+        proxy(&index_scheduler, &index_uid, &req, origin, network, Body::Inline(body), &task)
+            .await?;
     }
 
     let task: SummarizedTaskView = task.into();
@@ -1254,6 +1259,7 @@ pub async fn delete_documents_by_filter(
     let index_uid = index_uid.into_inner();
     let filter = body.into_inner();
     let network = index_scheduler.network();
+    let origin = check_leader(&req, &network)?;
 
     analytics.publish(
         DocumentsDeletionAggregator {
@@ -1286,7 +1292,8 @@ pub async fn delete_documents_by_filter(
     };
 
     if network.sharding && !dry_run {
-        proxy(&index_scheduler, &index_uid, &req, network, Body::Inline(filter), &task).await?;
+        proxy(&index_scheduler, &index_uid, &req, origin, network, Body::Inline(filter), &task)
+            .await?;
     }
 
     let task: SummarizedTaskView = task.into();
@@ -1384,6 +1391,7 @@ pub async fn edit_documents_by_function(
         .check_edit_documents_by_function("Using the documents edit route")?;
 
     let network = index_scheduler.network();
+    let origin = check_leader(&req, &network)?;
 
     let index_uid = IndexUid::try_from(index_uid.into_inner())?;
     let index_uid = index_uid.into_inner();
@@ -1436,7 +1444,8 @@ pub async fn edit_documents_by_function(
     };
 
     if network.sharding && !dry_run {
-        proxy(&index_scheduler, &index_uid, &req, network, Body::Inline(params), &task).await?;
+        proxy(&index_scheduler, &index_uid, &req, origin, network, Body::Inline(params), &task)
+            .await?;
     }
 
     let task: SummarizedTaskView = task.into();
@@ -1483,6 +1492,7 @@ pub async fn clear_all_documents(
 ) -> Result<HttpResponse, ResponseError> {
     let index_uid = IndexUid::try_from(index_uid.into_inner())?;
     let network = index_scheduler.network();
+    let origin = check_leader(&req, &network)?;
 
     analytics.publish(
         DocumentsDeletionAggregator {
@@ -1505,7 +1515,7 @@ pub async fn clear_all_documents(
     };
 
     if network.sharding && !dry_run {
-        proxy(&index_scheduler, &index_uid, &req, network, Body::none(), &task).await?;
+        proxy(&index_scheduler, &index_uid, &req, origin, network, Body::none(), &task).await?;
     }
 
     let task: SummarizedTaskView = task.into();

crates/meilisearch/src/routes/indexes/enterprise_edition/proxy.rs

@@ -38,6 +38,27 @@ impl Body<()> {
     }
 }
 
+pub fn check_leader(
+    req: &HttpRequest,
+    network: &meilisearch_types::enterprise_edition::network::DbNetwork,
+) -> Result<Option<Origin>, MeilisearchHttpError> {
+    match origin_from_req(req)? {
+        Some(origin) => Ok(Some(origin)),
+        None => {
+            let this = network
+                .local
+                .as_deref()
+                .expect("inconsistent `network.sharding` and `network.self`");
+
+            let is_leader = this == todo!();
+            if !is_leader {
+                return Err(MeilisearchHttpError::NotLeader { leader: todo!() });
+            }
+            Ok(None)
+        }
+    }
+}
+
 /// If necessary, proxies the passed request to the network and update the task description.
 ///
 /// This function reads the custom headers from the request to determine if must proxy the request or if the request
@@ -52,11 +73,12 @@ pub async fn proxy<T: serde::Serialize>(
     index_scheduler: &IndexScheduler,
     index_uid: &str,
     req: &HttpRequest,
-    network: meilisearch_types::enterprise_edition::network::Network,
+    origin: Option<Origin>,
+    network: meilisearch_types::enterprise_edition::network::DbNetwork,
     body: Body<T>,
     task: &meilisearch_types::tasks::Task,
 ) -> Result<(), MeilisearchHttpError> {
-    match origin_from_req(req)? {
+    match origin {
         Some(origin) => {
             index_scheduler.set_task_network(task.uid, TaskNetwork::Origin { origin })?
         }

crates/meilisearch/src/routes/indexes/facet_search.rs

@@ -260,7 +260,7 @@ pub async fn search(
     }
 
     let index = index_scheduler.index(&index_uid)?;
-    let search_kind = search_kind(&search_query, &index_scheduler, index_uid.to_string(), &index)?;
+    let search_kind = search_kind(&search_query, &index_scheduler, &index_uid, &index)?;
     let permit = search_queue.try_get_search_permit().await?;
     let search_result = tokio::task::spawn_blocking(move || {
         perform_facet_search(

crates/meilisearch/src/routes/indexes/search.rs

@@ -339,13 +339,12 @@ pub async fn search_with_url_query(
 
     let index = index_scheduler.index(&index_uid)?;
 
-    let search_kind =
-        search_kind(&query, index_scheduler.get_ref(), index_uid.to_string(), &index)?;
+    let search_kind = search_kind(&query, index_scheduler.get_ref(), &index_uid, &index)?;
     let retrieve_vector = RetrieveVectors::new(query.retrieve_vectors);
     let permit = search_queue.try_get_search_permit().await?;
     let search_result = tokio::task::spawn_blocking(move || {
         perform_search(
-            index_uid.to_string(),
+            &index_uid,
             &index,
             query,
             search_kind,
@@ -445,14 +444,13 @@ pub async fn search_with_post(
 
     let index = index_scheduler.index(&index_uid)?;
 
-    let search_kind =
-        search_kind(&query, index_scheduler.get_ref(), index_uid.to_string(), &index)?;
+    let search_kind = search_kind(&query, index_scheduler.get_ref(), &index_uid, &index)?;
     let retrieve_vectors = RetrieveVectors::new(query.retrieve_vectors);
 
     let permit = search_queue.try_get_search_permit().await?;
     let search_result = tokio::task::spawn_blocking(move || {
         perform_search(
-            index_uid.to_string(),
+            &index_uid,
             &index,
             query,
             search_kind,
@@ -480,7 +478,7 @@ pub async fn search_with_post(
 pub fn search_kind(
     query: &SearchQuery,
     index_scheduler: &IndexScheduler,
-    index_uid: String,
+    index_uid: &str,
     index: &milli::Index,
 ) -> Result<SearchKind, ResponseError> {
     let is_placeholder_query =

crates/meilisearch/src/routes/indexes/similar.rs

@@ -227,7 +227,7 @@ async fn similar(
 
     let (embedder_name, embedder, quantized) = SearchKind::embedder(
         &index_scheduler,
-        index_uid.to_string(),
+        index_uid.as_str(),
         &index,
         &query.embedder,
         None,

crates/meilisearch/src/routes/mod.rs

@@ -39,7 +39,6 @@ use crate::routes::features::RuntimeTogglableFeatures;
 use crate::routes::indexes::documents::{DocumentDeletionByFilter, DocumentEditionByFunction};
 use crate::routes::indexes::IndexView;
 use crate::routes::multi_search::SearchResults;
-use crate::routes::network::{Network, Remote};
 use crate::routes::swap_indexes::SwapIndexesPayload;
 use crate::routes::webhooks::{WebhookResults, WebhookSettings, WebhookWithMetadata};
 use crate::search::{
@@ -102,7 +101,7 @@ mod webhooks;
         url = "/",
         description = "Local server",
     )),
-    components(schemas(PaginationView<KeyView>, PaginationView<IndexView>, IndexView, DocumentDeletionByFilter, AllBatches, BatchStats, ProgressStepView, ProgressView, BatchView, RuntimeTogglableFeatures, SwapIndexesPayload, DocumentEditionByFunction, MergeFacets, FederationOptions, SearchQueryWithIndex, Federation, FederatedSearch, FederatedSearchResult, SearchResults, SearchResultWithIndex, SimilarQuery, SimilarResult, PaginationView<serde_json::Value>, BrowseQuery, UpdateIndexRequest, IndexUid, IndexCreateRequest, KeyView, Action, CreateApiKey, UpdateStderrLogs, LogMode, GetLogs, IndexStats, Stats, HealthStatus, HealthResponse, VersionResponse, Code, ErrorType, AllTasks, TaskView, Status, DetailsView, ResponseError, Settings<Unchecked>, Settings<Checked>, TypoSettings, MinWordSizeTyposSetting, FacetingSettings, PaginationSettings, SummarizedTaskView, Kind, Network, Remote, FilterableAttributesRule, FilterableAttributesPatterns, AttributePatterns, FilterableAttributesFeatures, FilterFeatures, Export, WebhookSettings, WebhookResults, WebhookWithMetadata, meilisearch_types::milli::vector::VectorStoreBackend))
+    components(schemas(PaginationView<KeyView>, PaginationView<IndexView>, IndexView, DocumentDeletionByFilter, AllBatches, BatchStats, ProgressStepView, ProgressView, BatchView, RuntimeTogglableFeatures, SwapIndexesPayload, DocumentEditionByFunction, MergeFacets, FederationOptions, SearchQueryWithIndex, Federation, FederatedSearch, FederatedSearchResult, SearchResults, SearchResultWithIndex, SimilarQuery, SimilarResult, PaginationView<serde_json::Value>, BrowseQuery, UpdateIndexRequest, IndexUid, IndexCreateRequest, KeyView, Action, CreateApiKey, UpdateStderrLogs, LogMode, GetLogs, IndexStats, Stats, HealthStatus, HealthResponse, VersionResponse, Code, ErrorType, AllTasks, TaskView, Status, DetailsView, ResponseError, Settings<Unchecked>, Settings<Checked>, TypoSettings, MinWordSizeTyposSetting, FacetingSettings, PaginationSettings, SummarizedTaskView, Kind, meilisearch_types::enterprise_edition::network::Network, meilisearch_types::enterprise_edition::network::Remote, FilterableAttributesRule, FilterableAttributesPatterns, AttributePatterns, FilterableAttributesFeatures, FilterFeatures, Export, WebhookSettings, WebhookResults, WebhookWithMetadata, meilisearch_types::milli::vector::VectorStoreBackend))
 )]
 pub struct MeilisearchApi;
 

crates/meilisearch/src/routes/multi_search.rs

@@ -239,26 +239,23 @@ pub async fn multi_search_with_post(
                         })
                         .with_index(query_index)?;
 
-                    let index_uid_str = index_uid.to_string();
-
-                    let search_kind = search_kind(
-                        &query,
-                        index_scheduler.get_ref(),
-                        index_uid_str.clone(),
-                        &index,
-                    )
-                    .with_index(query_index)?;
+                    let search_kind =
+                        search_kind(&query, index_scheduler.get_ref(), &index_uid, &index)
+                            .with_index(query_index)?;
                     let retrieve_vector = RetrieveVectors::new(query.retrieve_vectors);
 
-                    let search_result = tokio::task::spawn_blocking(move || {
-                        perform_search(
-                            index_uid_str.clone(),
-                            &index,
-                            query,
-                            search_kind,
-                            retrieve_vector,
-                            features,
-                        )
+                    let search_result = tokio::task::spawn_blocking({
+                        let index_uid = index_uid.clone();
+                        move || {
+                            perform_search(
+                                &index_uid,
+                                &index,
+                                query,
+                                search_kind,
+                                retrieve_vector,
+                                features,
+                            )
+                        }
                     })
                     .await
                     .with_index(query_index)?;

crates/meilisearch/src/routes/network.rs

@@ -1,28 +1,21 @@
-use std::collections::BTreeMap;
-
 use actix_web::web::{self, Data};
 use actix_web::{HttpRequest, HttpResponse};
 use deserr::actix_web::AwebJson;
-use deserr::Deserr;
 use index_scheduler::IndexScheduler;
-use itertools::{EitherOrBoth, Itertools};
 use meilisearch_types::deserr::DeserrJsonError;
-use meilisearch_types::enterprise_edition::network::{Network as DbNetwork, Remote as DbRemote};
-use meilisearch_types::error::deserr_codes::{
-    InvalidNetworkRemotes, InvalidNetworkSearchApiKey, InvalidNetworkSelf, InvalidNetworkSharding,
-    InvalidNetworkUrl, InvalidNetworkWriteApiKey,
-};
+use meilisearch_types::enterprise_edition::network::{Network, Remote};
 use meilisearch_types::error::ResponseError;
 use meilisearch_types::keys::actions;
 use meilisearch_types::milli::update::Setting;
 use serde::Serialize;
 use tracing::debug;
-use utoipa::{OpenApi, ToSchema};
+use utoipa::OpenApi;
 
 use crate::analytics::{Aggregate, Analytics};
 use crate::extractors::authentication::policies::ActionPolicy;
 use crate::extractors::authentication::GuardedData;
 use crate::extractors::sequential_extractor::SeqHandler;
+use crate::routes::SummarizedTaskView;
 
 #[derive(OpenApi)]
 #[openapi(
@@ -31,7 +24,7 @@ use crate::extractors::sequential_extractor::SeqHandler;
         name = "Network",
         description = "The `/network` route allows you to describe the topology of a network of Meilisearch instances.
 
-This route is **synchronous**. This means that no task object will be returned, and any change to the network will be made available immediately.",
+This route is **asynchronous**. A task uid will be returned, and any change to the network will be effective after the corresponding task has been processed.",
         external_docs(url = "https://www.meilisearch.com/docs/reference/api/network"),
     )),
 )]
@@ -83,73 +76,6 @@ async fn get_network(
     Ok(HttpResponse::Ok().json(network))
 }
 
-#[derive(Debug, Deserr, ToSchema, Serialize)]
-#[deserr(error = DeserrJsonError<InvalidNetworkRemotes>, rename_all = camelCase, deny_unknown_fields)]
-#[serde(rename_all = "camelCase")]
-#[schema(rename_all = "camelCase")]
-pub struct Remote {
-    #[schema(value_type = Option<String>, example = json!({
-        "ms-0": Remote { url: Setting::Set("http://localhost:7700".into()), search_api_key: Setting::Reset, write_api_key: Setting::Reset },
-        "ms-1": Remote { url: Setting::Set("http://localhost:7701".into()), search_api_key: Setting::Set("foo".into()), write_api_key: Setting::Set("bar".into()) },
-        "ms-2": Remote { url: Setting::Set("http://localhost:7702".into()), search_api_key: Setting::Set("bar".into()), write_api_key: Setting::Set("foo".into()) },
-    }))]
-    #[deserr(default, error = DeserrJsonError<InvalidNetworkUrl>)]
-    #[serde(default)]
-    pub url: Setting<String>,
-    #[schema(value_type = Option<String>, example = json!("XWnBI8QHUc-4IlqbKPLUDuhftNq19mQtjc6JvmivzJU"))]
-    #[deserr(default, error = DeserrJsonError<InvalidNetworkSearchApiKey>)]
-    #[serde(default)]
-    pub search_api_key: Setting<String>,
-    #[schema(value_type = Option<String>, example = json!("XWnBI8QHUc-4IlqbKPLUDuhftNq19mQtjc6JvmivzJU"))]
-    #[deserr(default, error = DeserrJsonError<InvalidNetworkWriteApiKey>)]
-    #[serde(default)]
-    pub write_api_key: Setting<String>,
-}
-
-#[derive(Debug, Deserr, ToSchema, Serialize)]
-#[deserr(error = DeserrJsonError, rename_all = camelCase, deny_unknown_fields)]
-#[serde(rename_all = "camelCase")]
-#[schema(rename_all = "camelCase")]
-pub struct Network {
-    #[schema(value_type = Option<BTreeMap<String, Remote>>, example = json!("http://localhost:7700"))]
-    #[deserr(default, error = DeserrJsonError<InvalidNetworkRemotes>)]
-    #[serde(default)]
-    pub remotes: Setting<BTreeMap<String, Option<Remote>>>,
-    #[schema(value_type = Option<String>, example = json!("ms-00"), rename = "self")]
-    #[serde(default, rename = "self")]
-    #[deserr(default, rename = "self", error = DeserrJsonError<InvalidNetworkSelf>)]
-    pub local: Setting<String>,
-    #[schema(value_type = Option<bool>, example = json!(true))]
-    #[serde(default)]
-    #[deserr(default, error = DeserrJsonError<InvalidNetworkSharding>)]
-    pub sharding: Setting<bool>,
-}
-
-impl Remote {
-    pub fn try_into_db_node(self, name: &str) -> Result<DbRemote, ResponseError> {
-        Ok(DbRemote {
-            url: self
-                .url
-                .set()
-                .ok_or(ResponseError::from_msg(
-                    format!("Missing field `.remotes.{name}.url`"),
-                    meilisearch_types::error::Code::MissingNetworkUrl,
-                ))
-                .and_then(|url| {
-                    if let Err(error) = url::Url::parse(&url) {
-                        return Err(ResponseError::from_msg(
-                            format!("Invalid `.remotes.{name}.url` (`{url}`): {error}"),
-                            meilisearch_types::error::Code::InvalidNetworkUrl,
-                        ));
-                    }
-                    Ok(url)
-                })?,
-            search_api_key: self.search_api_key.set(),
-            write_api_key: self.write_api_key.set(),
-        })
-    }
-}
-
 #[derive(Serialize)]
 pub struct PatchNetworkAnalytics {
     network_size: usize,
@@ -208,111 +134,58 @@ async fn patch_network(
     index_scheduler.features().check_network("Using the /network route")?;
 
     let new_network = new_network.0;
-    let old_network = index_scheduler.network();
     debug!(parameters = ?new_network, "Patch network");
 
-    let merged_self = match new_network.local {
-        Setting::Set(new_self) => Some(new_self),
-        Setting::Reset => None,
-        Setting::NotSet => old_network.local,
-    };
-
-    let merged_sharding = match new_network.sharding {
-        Setting::Set(new_sharding) => new_sharding,
-        Setting::Reset => false,
-        Setting::NotSet => old_network.sharding,
-    };
-
-    if merged_sharding && merged_self.is_none() {
-        return Err(ResponseError::from_msg(
-            "`.sharding`: enabling the sharding requires `.self` to be set\n  - Hint: Disable `sharding` or set `self` to a value.".into(),
-            meilisearch_types::error::Code::InvalidNetworkSharding,
-        ));
-    }
-
-    let merged_remotes = match new_network.remotes {
-        Setting::Set(new_remotes) => {
-            let mut merged_remotes = BTreeMap::new();
-            for either_or_both in old_network
-                .remotes
-                .into_iter()
-                .merge_join_by(new_remotes.into_iter(), |left, right| left.0.cmp(&right.0))
-            {
-                match either_or_both {
-                    EitherOrBoth::Both((key, old), (_, Some(new))) => {
-                        let DbRemote {
-                            url: old_url,
-                            search_api_key: old_search_api_key,
-                            write_api_key: old_write_api_key,
-                        } = old;
-
-                        let Remote {
-                            url: new_url,
-                            search_api_key: new_search_api_key,
-                            write_api_key: new_write_api_key,
-                        } = new;
-
-                        let merged = DbRemote {
-                            url: match new_url {
-                                Setting::Set(new_url) => {
-                                    if let Err(error) = url::Url::parse(&new_url) {
-                                        return Err(ResponseError::from_msg(
-                                            format!("Invalid `.remotes.{key}.url` (`{new_url}`): {error}"),
-                                            meilisearch_types::error::Code::InvalidNetworkUrl,
-                                        ));
-                                    }
-                                    new_url
-                                }
-                                Setting::Reset => {
-                                    return Err(ResponseError::from_msg(
-                                        format!(
-                                            "Field `.remotes.{key}.url` cannot be set to `null`"
-                                        ),
-                                        meilisearch_types::error::Code::InvalidNetworkUrl,
-                                    ))
-                                }
-                                Setting::NotSet => old_url,
-                            },
-                            search_api_key: match new_search_api_key {
-                                Setting::Set(new_search_api_key) => Some(new_search_api_key),
-                                Setting::Reset => None,
-                                Setting::NotSet => old_search_api_key,
-                            },
-                            write_api_key: match new_write_api_key {
-                                Setting::Set(new_write_api_key) => Some(new_write_api_key),
-                                Setting::Reset => None,
-                                Setting::NotSet => old_write_api_key,
-                            },
-                        };
-                        merged_remotes.insert(key, merged);
-                    }
-                    EitherOrBoth::Both((_, _), (_, None)) | EitherOrBoth::Right((_, None)) => {}
-                    EitherOrBoth::Left((key, node)) => {
-                        merged_remotes.insert(key, node);
-                    }
-                    EitherOrBoth::Right((key, Some(node))) => {
-                        let node = node.try_into_db_node(&key)?;
-                        merged_remotes.insert(key, node);
+    // check the URLs of all remotes
+    if let Setting::Set(remotes) = &new_network.remotes {
+        for (remote_name, remote) in remotes.iter() {
+            let Some(remote) = remote else {
+                continue;
+            };
+            match &remote.url {
+                Setting::Set(new_url) => {
+                    if let Err(error) = url::Url::parse(&new_url) {
+                        return Err(ResponseError::from_msg(
+                            format!("Invalid `.remotes.{remote_name}.url` (`{new_url}`): {error}"),
+                            meilisearch_types::error::Code::InvalidNetworkUrl,
+                        ));
                     }
                 }
+                Setting::Reset => {
+                    return Err(ResponseError::from_msg(
+                        format!("Field `.remotes.{remote_name}.url` cannot be set to `null`"),
+                        meilisearch_types::error::Code::InvalidNetworkUrl,
+                    ))
+                }
+                Setting::NotSet => (),
             }
-            merged_remotes
         }
-        Setting::Reset => BTreeMap::new(),
-        Setting::NotSet => old_network.remotes,
-    };
+    }
 
     analytics.publish(
         PatchNetworkAnalytics {
-            network_size: merged_remotes.len(),
-            network_has_self: merged_self.is_some(),
+            network_size: new_network
+                .remotes
+                .as_ref()
+                .set()
+                .map(|remotes| remotes.len())
+                .unwrap_or_default(),
+            network_has_self: new_network.local.as_ref().set().is_some(),
         },
         &req,
     );
 
-    let merged_network =
-        DbNetwork { local: merged_self, remotes: merged_remotes, sharding: merged_sharding };
-    index_scheduler.put_network(merged_network.clone())?;
-    debug!(returns = ?merged_network, "Patch network");
-    Ok(HttpResponse::Ok().json(merged_network))
+    let task = index_scheduler.register(
+        meilisearch_types::tasks::KindWithContent::NetworkTopologyChange {
+            network: Some(new_network),
+            origin: None,
+        },
+        None,
+        false,
+    )?;
+    debug!(returns = ?task, "Patch network");
+
+    let task: SummarizedTaskView = task.into();
+
+    return Ok(HttpResponse::Accepted().json(task));
 }

crates/meilisearch/src/routes/tasks_test.rs

@@ -226,14 +226,14 @@ mod tests {
         {
             let params = "types=createIndex";
             let err = deserr_query_params::<TaskDeletionOrCancelationQuery>(params).unwrap_err();
-            snapshot!(meili_snap::json_string!(err), @r#"
+            snapshot!(meili_snap::json_string!(err), @r###"
             {
-              "message": "Invalid value in parameter `types`: `createIndex` is not a valid task type. Available types are `documentAdditionOrUpdate`, `documentEdition`, `documentDeletion`, `settingsUpdate`, `indexCreation`, `indexDeletion`, `indexUpdate`, `indexSwap`, `taskCancelation`, `taskDeletion`, `dumpCreation`, `snapshotCreation`, `export`, `upgradeDatabase`.",
+              "message": "Invalid value in parameter `types`: `createIndex` is not a valid task type. Available types are `documentAdditionOrUpdate`, `documentEdition`, `documentDeletion`, `settingsUpdate`, `indexCreation`, `indexDeletion`, `indexUpdate`, `indexSwap`, `taskCancelation`, `taskDeletion`, `dumpCreation`, `snapshotCreation`, `export`, `upgradeDatabase`, `networkTopologyChange`.",
               "code": "invalid_task_types",
               "type": "invalid_request",
               "link": "https://docs.meilisearch.com/errors#invalid_task_types"
             }
-            "#);
+            "###);
         }
     }
     #[test]

crates/meilisearch/src/search/federated/perform.rs

@@ -9,7 +9,7 @@ use std::vec::{IntoIter, Vec};
 use actix_http::StatusCode;
 use index_scheduler::{IndexScheduler, RoFeatures};
 use itertools::Itertools;
-use meilisearch_types::enterprise_edition::network::{Network, Remote};
+use meilisearch_types::enterprise_edition::network::{DbNetwork, DbRemote};
 use meilisearch_types::error::ResponseError;
 use meilisearch_types::milli::order_by_map::OrderByMap;
 use meilisearch_types::milli::score_details::{ScoreDetails, WeightedScoreValue};
@@ -456,7 +456,7 @@ fn merge_metadata(
 }
 
 type LocalQueriesByIndex = BTreeMap<String, Vec<QueryByIndex>>;
-type RemoteQueriesByHost = BTreeMap<String, (Remote, Vec<SearchQueryWithIndex>)>;
+type RemoteQueriesByHost = BTreeMap<String, (DbRemote, Vec<SearchQueryWithIndex>)>;
 
 struct PartitionedQueries {
     local_queries_by_index: LocalQueriesByIndex,
@@ -477,7 +477,7 @@ impl PartitionedQueries {
         &mut self,
         federated_query: SearchQueryWithIndex,
         query_index: usize,
-        network: &Network,
+        network: &DbNetwork,
         features: RoFeatures,
     ) -> Result<(), ResponseError> {
         if let Some(pagination_field) = federated_query.has_pagination() {
@@ -672,7 +672,7 @@ struct SearchByIndexParams<'a> {
     features: RoFeatures,
     is_proxy: bool,
     has_remote: bool,
-    network: &'a Network,
+    network: &'a DbNetwork,
 }
 
 struct SearchByIndex {
@@ -755,8 +755,7 @@ impl SearchByIndex {
             // use an immediately invoked lambda to capture the result without returning from the function
 
             let res: Result<(), ResponseError> = (|| {
-                let search_kind =
-                    search_kind(&query, params.index_scheduler, index_uid.to_string(), &index)?;
+                let search_kind = search_kind(&query, params.index_scheduler, &index_uid, &index)?;
 
                 let canonicalization_kind = match (&search_kind, &query.q) {
                     (SearchKind::SemanticOnly { .. }, _) => {
@@ -806,11 +805,11 @@ impl SearchByIndex {
                     {
                         Some((previous_ranking_rules, previous_query_index, previous_index_uid))
                     } else {
-                        Some((ranking_rules, query_index, index_uid.clone()))
+                        Some((ranking_rules, query_index, index_uid.to_string()))
                     };
                 } else {
                     self.previous_query_data =
-                        Some((ranking_rules, query_index, index_uid.clone()));
+                        Some((ranking_rules, query_index, index_uid.to_string()));
                 }
 
                 match search_kind {
@@ -839,7 +838,7 @@ impl SearchByIndex {
                 search.limit(params.required_hit_count);
 
                 let (result, _semantic_hit_count) =
-                    super::super::search_from_kind(index_uid.to_string(), search_kind, search)?;
+                    super::super::search_from_kind(&index_uid, search_kind, search)?;
                 let format = AttributesFormat {
                     attributes_to_retrieve: query.attributes_to_retrieve,
                     retrieve_vectors,

crates/meilisearch/src/search/federated/proxy.rs

@@ -1,6 +1,6 @@
 pub use error::ProxySearchError;
 use error::ReqwestErrorWithoutUrl;
-use meilisearch_types::enterprise_edition::network::Remote;
+use meilisearch_types::enterprise_edition::network::DbRemote;
 use rand::Rng as _;
 use reqwest::{Client, Response, StatusCode};
 use serde::de::DeserializeOwned;
@@ -94,7 +94,7 @@ pub struct ProxySearchParams {
 
 /// Performs a federated search on a remote host and returns the results
 pub async fn proxy_search(
-    node: &Remote,
+    node: &DbRemote,
     queries: Vec<SearchQueryWithIndex>,
     federation: Federation,
     params: &ProxySearchParams,

crates/meilisearch/src/search/mod.rs

@@ -362,7 +362,7 @@ pub enum SearchKind {
 impl SearchKind {
     pub(crate) fn semantic(
         index_scheduler: &index_scheduler::IndexScheduler,
-        index_uid: String,
+        index_uid: &str,
         index: &Index,
         embedder_name: &str,
         vector_len: Option<usize>,
@@ -380,7 +380,7 @@ impl SearchKind {
 
     pub(crate) fn hybrid(
         index_scheduler: &index_scheduler::IndexScheduler,
-        index_uid: String,
+        index_uid: &str,
         index: &Index,
         embedder_name: &str,
         semantic_ratio: f32,
@@ -399,7 +399,7 @@ impl SearchKind {
 
     pub(crate) fn embedder(
         index_scheduler: &index_scheduler::IndexScheduler,
-        index_uid: String,
+        index_uid: &str,
         index: &Index,
         embedder_name: &str,
         vector_len: Option<usize>,
@@ -1114,7 +1114,7 @@ pub fn prepare_search<'t>(
 }
 
 pub fn perform_search(
-    index_uid: String,
+    index_uid: &str,
     index: &Index,
     query: SearchQuery,
     search_kind: SearchKind,
@@ -1299,27 +1299,24 @@ fn compute_facet_distribution_stats<S: AsRef<str>>(
 }
 
 pub fn search_from_kind(
-    index_uid: String,
+    index_uid: &str,
     search_kind: SearchKind,
     search: milli::Search<'_>,
 ) -> Result<(milli::SearchResult, Option<u32>), MeilisearchHttpError> {
+    let err = |e| MeilisearchHttpError::from_milli(e, Some(index_uid.to_string()));
     let (milli_result, semantic_hit_count) = match &search_kind {
         SearchKind::KeywordOnly => {
-            let results = search
-                .execute()
-                .map_err(|e| MeilisearchHttpError::from_milli(e, Some(index_uid.to_string())))?;
+            let results = search.execute().map_err(err)?;
             (results, None)
         }
         SearchKind::SemanticOnly { .. } => {
-            let results = search
-                .execute()
-                .map_err(|e| MeilisearchHttpError::from_milli(e, Some(index_uid.to_string())))?;
+            let results = search.execute().map_err(err)?;
             let semantic_hit_count = results.document_scores.len() as u32;
             (results, Some(semantic_hit_count))
         }
-        SearchKind::Hybrid { semantic_ratio, .. } => search
-            .execute_hybrid(*semantic_ratio)
-            .map_err(|e| MeilisearchHttpError::from_milli(e, Some(index_uid)))?,
+        SearchKind::Hybrid { semantic_ratio, .. } => {
+            search.execute_hybrid(*semantic_ratio).map_err(err)?
+        }
     };
     Ok((milli_result, semantic_hit_count))
 }

crates/meilisearch/tests/batches/errors.rs

@@ -40,14 +40,14 @@ async fn batch_bad_types() {
 
     let (response, code) = server.batches_filter("types=doggo").await;
     snapshot!(code, @"400 Bad Request");
-    snapshot!(json_string!(response), @r#"
+    snapshot!(json_string!(response), @r###"
     {
-      "message": "Invalid value in parameter `types`: `doggo` is not a valid task type. Available types are `documentAdditionOrUpdate`, `documentEdition`, `documentDeletion`, `settingsUpdate`, `indexCreation`, `indexDeletion`, `indexUpdate`, `indexSwap`, `taskCancelation`, `taskDeletion`, `dumpCreation`, `snapshotCreation`, `export`, `upgradeDatabase`.",
+      "message": "Invalid value in parameter `types`: `doggo` is not a valid task type. Available types are `documentAdditionOrUpdate`, `documentEdition`, `documentDeletion`, `settingsUpdate`, `indexCreation`, `indexDeletion`, `indexUpdate`, `indexSwap`, `taskCancelation`, `taskDeletion`, `dumpCreation`, `snapshotCreation`, `export`, `upgradeDatabase`, `networkTopologyChange`.",
       "code": "invalid_task_types",
       "type": "invalid_request",
       "link": "https://docs.meilisearch.com/errors#invalid_task_types"
     }
-    "#);
+    "###);
 }
 
 #[actix_rt::test]

crates/meilisearch/tests/common/server.rs

@@ -49,8 +49,8 @@ impl Server<Owned> {
         }
 
         let options = default_settings(dir.path());
-
-        let (index_scheduler, auth) = setup_meilisearch(&options).unwrap();
+        let handle = tokio::runtime::Handle::current();
+        let (index_scheduler, auth) = setup_meilisearch(&options, handle).unwrap();
         let service = Service { index_scheduler, auth, options, api_key: None };
 
         Server { service, _dir: Some(dir), _marker: PhantomData }
@@ -65,7 +65,9 @@ impl Server<Owned> {
 
         options.master_key = Some("MASTER_KEY".to_string());
 
-        let (index_scheduler, auth) = setup_meilisearch(&options).unwrap();
+        let handle = tokio::runtime::Handle::current();
+
+        let (index_scheduler, auth) = setup_meilisearch(&options, handle).unwrap();
         let service = Service { index_scheduler, auth, options, api_key: None };
 
         Server { service, _dir: Some(dir), _marker: PhantomData }
@@ -78,7 +80,9 @@ impl Server<Owned> {
     }
 
     pub async fn new_with_options(options: Opt) -> Result<Self, anyhow::Error> {
-        let (index_scheduler, auth) = setup_meilisearch(&options)?;
+        let handle = tokio::runtime::Handle::current();
+
+        let (index_scheduler, auth) = setup_meilisearch(&options, handle)?;
         let service = Service { index_scheduler, auth, options, api_key: None };
 
         Ok(Server { service, _dir: None, _marker: PhantomData })
@@ -217,8 +221,9 @@ impl Server<Shared> {
         }
 
         let options = default_settings(dir.path());
+        let handle = tokio::runtime::Handle::current();
 
-        let (index_scheduler, auth) = setup_meilisearch(&options).unwrap();
+        let (index_scheduler, auth) = setup_meilisearch(&options, handle).unwrap();
         let service = Service { index_scheduler, auth, api_key: None, options };
 
         Server { service, _dir: Some(dir), _marker: PhantomData }

crates/meilisearch/tests/search/multi/proxy.rs

@@ -127,7 +127,7 @@ async fn remote_sharding() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -136,7 +136,7 @@ async fn remote_sharding() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -145,7 +145,7 @@ async fn remote_sharding() {
     }
     "###);
     let (response, code) = ms2.set_network(json!({"self": "ms2"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms2",
@@ -192,11 +192,11 @@ async fn remote_sharding() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms1.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms2.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -442,7 +442,7 @@ async fn remote_sharding_retrieve_vectors() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -451,7 +451,7 @@ async fn remote_sharding_retrieve_vectors() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -460,7 +460,7 @@ async fn remote_sharding_retrieve_vectors() {
     }
     "###);
     let (response, code) = ms2.set_network(json!({"self": "ms2"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms2",
@@ -542,11 +542,11 @@ async fn remote_sharding_retrieve_vectors() {
     }});
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms1.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms2.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // multi vector search: one query per remote
 
@@ -935,7 +935,7 @@ async fn error_unregistered_remote() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -944,7 +944,7 @@ async fn error_unregistered_remote() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -983,9 +983,9 @@ async fn error_unregistered_remote() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms1.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -1055,7 +1055,7 @@ async fn error_no_weighted_score() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -1064,7 +1064,7 @@ async fn error_no_weighted_score() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -1107,7 +1107,7 @@ async fn error_no_weighted_score() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -1190,7 +1190,7 @@ async fn error_bad_response() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -1199,7 +1199,7 @@ async fn error_bad_response() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -1245,7 +1245,7 @@ async fn error_bad_response() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -1329,7 +1329,7 @@ async fn error_bad_request() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -1338,7 +1338,7 @@ async fn error_bad_request() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -1377,7 +1377,7 @@ async fn error_bad_request() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -1461,7 +1461,7 @@ async fn error_bad_request_facets_by_index() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -1470,7 +1470,7 @@ async fn error_bad_request_facets_by_index() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -1510,7 +1510,7 @@ async fn error_bad_request_facets_by_index() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -1604,7 +1604,7 @@ async fn error_bad_request_facets_by_index_facet() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -1613,7 +1613,7 @@ async fn error_bad_request_facets_by_index_facet() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -1656,7 +1656,7 @@ async fn error_bad_request_facets_by_index_facet() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -1756,7 +1756,7 @@ async fn error_remote_does_not_answer() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -1765,7 +1765,7 @@ async fn error_remote_does_not_answer() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -1807,9 +1807,9 @@ async fn error_remote_does_not_answer() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms1.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -1959,7 +1959,7 @@ async fn error_remote_404() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -1968,7 +1968,7 @@ async fn error_remote_404() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -2007,9 +2007,9 @@ async fn error_remote_404() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms1.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -2156,7 +2156,7 @@ async fn error_remote_sharding_auth() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -2165,7 +2165,7 @@ async fn error_remote_sharding_auth() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -2211,7 +2211,7 @@ async fn error_remote_sharding_auth() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -2318,7 +2318,7 @@ async fn remote_sharding_auth() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -2327,7 +2327,7 @@ async fn remote_sharding_auth() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -2372,7 +2372,7 @@ async fn remote_sharding_auth() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -2475,7 +2475,7 @@ async fn error_remote_500() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -2484,7 +2484,7 @@ async fn error_remote_500() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -2527,9 +2527,9 @@ async fn error_remote_500() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms1.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -2656,7 +2656,7 @@ async fn error_remote_500_once() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -2665,7 +2665,7 @@ async fn error_remote_500_once() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -2708,9 +2708,9 @@ async fn error_remote_500_once() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms1.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";
@@ -2841,7 +2841,7 @@ async fn error_remote_timeout() {
     // set self
 
     let (response, code) = ms0.set_network(json!({"self": "ms0"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms0",
@@ -2849,7 +2849,7 @@ async fn error_remote_timeout() {
     }
     "###);
     let (response, code) = ms1.set_network(json!({"self": "ms1"})).await;
-    snapshot!(code, @"200 OK");
+    snapshot!(code, @"202 Accepted");
     snapshot!(json_string!(response), @r###"
     {
       "self": "ms1",
@@ -2891,9 +2891,9 @@ async fn error_remote_timeout() {
     println!("{}", serde_json::to_string_pretty(&network).unwrap());
 
     let (_response, status_code) = ms0.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
     let (_response, status_code) = ms1.set_network(network.clone()).await;
-    snapshot!(status_code, @"200 OK");
+    snapshot!(status_code, @"202 Accepted");
 
     // perform multi-search
     let query = "badman returns";

crates/meilisearch/tests/tasks/errors.rs

@@ -95,14 +95,14 @@ async fn task_bad_types() {
 
     let (response, code) = server.tasks_filter("types=doggo").await;
     snapshot!(code, @"400 Bad Request");
-    snapshot!(json_string!(response), @r#"
+    snapshot!(json_string!(response), @r###"
     {
-      "message": "Invalid value in parameter `types`: `doggo` is not a valid task type. Available types are `documentAdditionOrUpdate`, `documentEdition`, `documentDeletion`, `settingsUpdate`, `indexCreation`, `indexDeletion`, `indexUpdate`, `indexSwap`, `taskCancelation`, `taskDeletion`, `dumpCreation`, `snapshotCreation`, `export`, `upgradeDatabase`.",
+      "message": "Invalid value in parameter `types`: `doggo` is not a valid task type. Available types are `documentAdditionOrUpdate`, `documentEdition`, `documentDeletion`, `settingsUpdate`, `indexCreation`, `indexDeletion`, `indexUpdate`, `indexSwap`, `taskCancelation`, `taskDeletion`, `dumpCreation`, `snapshotCreation`, `export`, `upgradeDatabase`, `networkTopologyChange`.",
       "code": "invalid_task_types",
       "type": "invalid_request",
       "link": "https://docs.meilisearch.com/errors#invalid_task_types"
     }
-    "#);
+    "###);
 
     let (response, code) = server.cancel_tasks("types=doggo").await;
     snapshot!(code, @"400 Bad Request");

crates/milli/src/error.rs

@@ -432,6 +432,10 @@ and can not be more than 511 bytes.", .document_id.to_string()
     InvalidChatSettingsDocumentTemplateMaxBytes,
     #[error("{0}")]
     DocumentEmbeddingError(String),
+    #[error("enabling the sharding requires `.self` to be set\n  - Hint: Disable `sharding` or set `self` to a value.")]
+    NetworkShardingWithoutSelf,
+    #[error("Field `.remotes.{0}.url` cannot be set to `null`")]
+    NetworkMissingUrl(String),
 }
 
 impl From<crate::vector::Error> for Error {

crates/milli/src/update/new/indexer/enterprise_edition/sharding.rs

@@ -5,18 +5,24 @@
 
 use std::hash::{BuildHasher as _, BuildHasherDefault};
 
-pub struct Shards {
-    pub own: Vec<String>,
-    pub others: Vec<String>,
+pub struct Shards(pub Vec<Shard>);
+
+pub struct Shard {
+    pub is_own: bool,
+    pub name: String,
 }
 
 impl Shards {
     pub fn must_process(&self, docid: &str) -> bool {
+        self.processing_shard(docid).map(|shard| shard.is_own).unwrap_or_default()
+    }
+
+    pub fn processing_shard<'a>(&'a self, docid: &str) -> Option<&'a Shard> {
         let hasher = BuildHasherDefault::<twox_hash::XxHash3_64>::new();
-        let to_hash = |shard: &String| hasher.hash_one((shard, docid));
+        let to_hash = |shard: &'a Shard| (shard, hasher.hash_one((&shard.name, docid)));
 
-        let max_hash = self.others.iter().map(to_hash).max().unwrap_or_default();
-
-        self.own.iter().map(to_hash).any(|hash| hash > max_hash)
+        let shard =
+            self.0.iter().map(to_hash).max_by_key(|(_, hash)| *hash).map(|(shard, _)| shard);
+        shard
     }
 }