Reintroduce the versioning functions

index-scheduler/src/batch.rs

@@ -33,7 +33,7 @@ use meilisearch_types::milli::update::{
 use meilisearch_types::milli::{self, BEU32};
 use meilisearch_types::settings::{apply_settings_to_builder, Settings, Unchecked};
 use meilisearch_types::tasks::{Details, Kind, KindWithContent, Status, Task};
-use meilisearch_types::Index;
+use meilisearch_types::{Index, VERSION_FILE_NAME};
 use roaring::RoaringBitmap;
 use time::OffsetDateTime;
 use uuid::Uuid;
@@ -559,9 +559,8 @@ impl IndexScheduler {
 
                 // 1. Snapshot the version file.
                 // TODO where can I find the path of this file and do we create it anyway?
-                // let dst = temp_snapshot_dir.path().join(VERSION_FILE_NAME);
-                // let src = self.base_path.join(VERSION_FILE_NAME);
-                // fs::copy(src, dst)?;
+                let dst = temp_snapshot_dir.path().join(VERSION_FILE_NAME);
+                fs::copy(&self.version_file_path, dst)?;
 
                 // TODO what is a meta-env in the previous version of the scheduler?
 
@@ -601,7 +600,7 @@ impl IndexScheduler {
                 // 3. Snapshot every indexes
                 // TODO we are opening all of the indexes it can be too much we should unload all
                 //      of the indexes we are trying to open. It would be even better to only unload
-                //      the one that were opened by us. Or maybe use a LRU in the index mapper.
+                //      the ones that were opened by us. Or maybe use a LRU in the index mapper.
                 for result in self.index_mapper.index_mapping.iter(&rtxn)? {
                     let (name, uuid) = result?;
                     let index = self.index_mapper.index(&rtxn, name)?;
@@ -618,7 +617,8 @@ impl IndexScheduler {
                 // 4. Snapshot the auth LMDB env
                 let dst = temp_snapshot_dir.path().join("auth").join("data.mdb");
                 fs::create_dir_all(&dst)?;
-                let auth = milli::heed::EnvOpenOptions::new().open(&self.auth_path)?;
+                let src = self.auth_path.join("data.mdb");
+                let auth = milli::heed::EnvOpenOptions::new().open(src)?;
                 auth.copy_to_path(dst, CompactionOption::Enabled)?;
 
                 todo!("tar-gz and append .snapshot at the end of the file");

index-scheduler/src/insta_snapshot.rs

@@ -28,6 +28,7 @@ pub fn snapshot_index_scheduler(scheduler: &IndexScheduler) -> String {
         dumps_path: _,
         snapshots_path: _,
         auth_path: _,
+        version_file_path: _,
         test_breakpoint_sdr: _,
         planned_failures: _,
         run_loop_iteration: _,

index-scheduler/src/lib.rs

@@ -248,6 +248,9 @@ pub struct IndexScheduler {
     /// The path to the folder containing the auth LMDB env.
     pub(crate) auth_path: PathBuf,
 
+    /// The path to the version file of Meilisearch.
+    pub(crate) version_file_path: PathBuf,
+
     // ================= test
     // The next entry is dedicated to the tests.
     /// Provide a way to set a breakpoint in multiple part of the scheduler.
@@ -286,6 +289,7 @@ impl IndexScheduler {
             snapshots_path: self.snapshots_path.clone(),
             dumps_path: self.dumps_path.clone(),
             auth_path: self.auth_path.clone(),
+            version_file_path: self.version_file_path.clone(),
             #[cfg(test)]
             test_breakpoint_sdr: self.test_breakpoint_sdr.clone(),
             #[cfg(test)]
@@ -314,6 +318,7 @@ impl IndexScheduler {
     /// Create an index scheduler and start its run loop.
     ///
     /// ## Arguments
+    /// - `version_file_path`: the path to the version file of Meilisearch
     /// - `auth_path`: the path to the folder containing the auth LMDB env
     /// - `tasks_path`: the path to the folder containing the task databases
     /// - `update_file_path`: the path to the file store containing the files associated to the tasks
@@ -326,6 +331,7 @@ impl IndexScheduler {
     /// together, to process multiple tasks at once.
     #[allow(clippy::too_many_arguments)]
     pub fn new(
+        version_file_path: PathBuf,
         auth_path: PathBuf,
         tasks_path: PathBuf,
         update_file_path: PathBuf,
@@ -371,6 +377,7 @@ impl IndexScheduler {
             dumps_path,
             snapshots_path,
             auth_path,
+            version_file_path,
 
             #[cfg(test)]
             test_breakpoint_sdr,
@@ -975,6 +982,8 @@ mod tests {
             let (sender, receiver) = crossbeam::channel::bounded(0);
 
             let index_scheduler = Self::new(
+                tempdir.path().join(VERSION_FILE_NAME),
+                tempdir.path().join("auth"),
                 tempdir.path().join("db_path"),
                 tempdir.path().join("file_store"),
                 tempdir.path().join("indexes"),