Change: move read_vote function from RaftLogStorage to RaftLogReader

cluster_benchmark/tests/benchmark/store.rs

@@ -121,6 +121,10 @@ impl RaftLogReader<TypeConfig> for Arc<LogStore> {
 
         Ok(entries)
     }
+
+    async fn read_vote(&mut self) -> Result<Option<Vote<NodeId>>, StorageError<NodeId>> {
+        Ok(self.vote.read().await.clone())
+    }
 }
 
 impl RaftSnapshotBuilder<TypeConfig> for Arc<StateMachineStore> {
@@ -204,10 +208,6 @@ impl RaftLogStorage<TypeConfig> for Arc<LogStore> {
         Ok(())
     }
 
-    async fn read_vote(&mut self) -> Result<Option<Vote<NodeId>>, StorageError<NodeId>> {
-        Ok(self.vote.read().await.clone())
-    }
-
     #[tracing::instrument(level = "debug", skip(self))]
     async fn truncate(&mut self, log_id: LogId<NodeId>) -> Result<(), StorageError<NodeId>> {
         let mut log = self.log.write().await;

examples/memstore/src/log_store.rs

@@ -156,6 +156,11 @@ mod impl_log_store {
             let mut inner = self.inner.lock().await;
             inner.try_get_log_entries(range).await
         }
+
+        async fn read_vote(&mut self) -> Result<Option<Vote<C::NodeId>>, StorageError<C::NodeId>> {
+            let mut inner = self.inner.lock().await;
+            inner.read_vote().await
+        }
     }
 
     impl<C: RaftTypeConfig> RaftLogStorage<C> for LogStore<C>
@@ -183,11 +188,6 @@ mod impl_log_store {
             inner.save_vote(vote).await
         }
 
-        async fn read_vote(&mut self) -> Result<Option<Vote<C::NodeId>>, StorageError<C::NodeId>> {
-            let mut inner = self.inner.lock().await;
-            inner.read_vote().await
-        }
-
         async fn append<I>(&mut self, entries: I, callback: LogFlushed<C>) -> Result<(), StorageError<C::NodeId>>
         where I: IntoIterator<Item = C::Entry> {
             let mut inner = self.inner.lock().await;

examples/raft-kv-memstore-singlethreaded/src/store.rs

@@ -127,6 +127,10 @@ impl RaftLogReader<TypeConfig> for Rc<LogStore> {
         let response = log.range(range.clone()).map(|(_, val)| val.clone()).collect::<Vec<_>>();
         Ok(response)
     }
+
+    async fn read_vote(&mut self) -> Result<Option<Vote<NodeId>>, StorageError<NodeId>> {
+        Ok(*self.vote.borrow())
+    }
 }
 
 impl RaftSnapshotBuilder<TypeConfig> for Rc<StateMachineStore> {
@@ -313,10 +317,6 @@ impl RaftLogStorage<TypeConfig> for Rc<LogStore> {
         Ok(())
     }
 
-    async fn read_vote(&mut self) -> Result<Option<Vote<NodeId>>, StorageError<NodeId>> {
-        Ok(*self.vote.borrow())
-    }
-
     #[tracing::instrument(level = "trace", skip(self, entries, callback))]
     async fn append<I>(&mut self, entries: I, callback: LogFlushed<TypeConfig>) -> Result<(), StorageError<NodeId>>
     where I: IntoIterator<Item = Entry<TypeConfig>> {

examples/raft-kv-rocksdb/src/store.rs

@@ -392,6 +392,10 @@ impl RaftLogReader<TypeConfig> for LogStore {
             .map(|x| x.1)
             .collect()
     }
+
+    async fn read_vote(&mut self) -> Result<Option<Vote<NodeId>>, StorageError<NodeId>> {
+        self.get_vote_()
+    }
 }
 
 impl RaftLogStorage<TypeConfig> for LogStore {
@@ -430,10 +434,6 @@ impl RaftLogStorage<TypeConfig> for LogStore {
         self.set_vote_(vote)
     }
 
-    async fn read_vote(&mut self) -> Result<Option<Vote<NodeId>>, StorageError<NodeId>> {
-        self.get_vote_()
-    }
-
     #[tracing::instrument(level = "trace", skip_all)]
     async fn append<I>(&mut self, entries: I, callback: LogFlushed<TypeConfig>) -> StorageResult<()>
     where

openraft/src/docs/getting_started/getting-started.md

@@ -96,7 +96,6 @@ Follow the link to method document to see the details.
 | Write log: | [`truncate()`]            | ()                           | delete logs `[index, +oo)`            |
 | Write log: | [`purge()`]               | ()                           | purge logs `(-oo, index]`             |
 | Vote:      | [`save_vote()`]           | ()                           | save vote                             |
-| Vote:      | [`read_vote()`]           | [`Vote`]                     | read vote                             |
 
 | Kind       | [`RaftStateMachine`] method    | Return value                 | Description                           |
 |------------|--------------------------------|------------------------------|---------------------------------------|
@@ -122,10 +121,12 @@ Most of the APIs are quite straightforward, except two indirect APIs:
 
     [`RaftLogReader`] defines the APIs to read logs, and is an also super trait of [`RaftLogStorage`] :
     - [`try_get_log_entries()`] get log entries in a range;
+    - [`read_vote()`] read vote;
 
     ```ignore
     trait RaftLogReader<C: RaftTypeConfig> {
         async fn try_get_log_entries<RB: RangeBounds<u64>>(&mut self, range: RB) -> Result<Vec<C::Entry>, ...>;
+        async fn read_vote(&mut self) -> Result<Option<Vote<C::NodeId>>, ...>>;
     }
     ```
 
@@ -372,6 +373,7 @@ Additionally, two test scripts for setting up a cluster are available:
 
 [`RaftLogReader`]:                      `crate::storage::RaftLogReader`
 [`try_get_log_entries()`]:              `crate::storage::RaftLogReader::try_get_log_entries`
+[`read_vote()`]:                        `crate::storage::RaftLogReader::read_vote`
 
 
 [`RaftLogStorage::SnapshotBuilder`]:    `crate::storage::RaftLogStorage::SnapshotBuilder`
@@ -382,7 +384,6 @@ Additionally, two test scripts for setting up a cluster are available:
 [`truncate()`]:                         `crate::storage::RaftLogStorage::truncate`
 [`purge()`]:                            `crate::storage::RaftLogStorage::purge`
 [`save_vote()`]:                        `crate::storage::RaftLogStorage::save_vote`
-[`read_vote()`]:                        `crate::storage::RaftLogStorage::read_vote`
 [`get_log_state()`]:                    `crate::storage::RaftLogStorage::get_log_state`
 [`get_log_reader()`]:                   `crate::storage::RaftLogStorage::get_log_reader`
 

openraft/src/storage/mod.rs

@@ -29,6 +29,7 @@ use crate::OptionalSync;
 use crate::RaftTypeConfig;
 use crate::StorageError;
 use crate::StoredMembership;
+use crate::Vote;
 
 #[derive(Debug, Clone, Default, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize), serde(bound = ""))]
@@ -149,6 +150,9 @@ where C: RaftTypeConfig
         &mut self,
         range: RB,
     ) -> Result<Vec<C::Entry>, StorageError<C::NodeId>>;
+
+    /// Return the last saved vote by [`RaftLogStorage::save_vote`].
+    async fn read_vote(&mut self) -> Result<Option<Vote<C::NodeId>>, StorageError<C::NodeId>>;
 }
 
 /// A trait defining the interface for a Raft state machine snapshot subsystem.

openraft/src/storage/v2.rs

@@ -66,9 +66,6 @@ where C: RaftTypeConfig
     /// The vote must be persisted on disk before returning.
     async fn save_vote(&mut self, vote: &Vote<C::NodeId>) -> Result<(), StorageError<C::NodeId>>;
 
-    /// Return the last saved vote by [`Self::save_vote`].
-    async fn read_vote(&mut self) -> Result<Option<Vote<C::NodeId>>, StorageError<C::NodeId>>;
-
     /// Saves the last committed log id to storage.
     ///
     /// # Optional feature

stores/memstore/src/lib.rs

@@ -243,6 +243,10 @@ impl RaftLogReader<TypeConfig> for Arc<MemLogStore> {
 
         Ok(entries)
     }
+
+    async fn read_vote(&mut self) -> Result<Option<Vote<MemNodeId>>, StorageError<MemNodeId>> {
+        Ok(*self.vote.read().await)
+    }
 }
 
 impl RaftSnapshotBuilder<TypeConfig> for Arc<MemStateMachine> {
@@ -352,10 +356,6 @@ impl RaftLogStorage<TypeConfig> for Arc<MemLogStore> {
         Ok(())
     }
 
-    async fn read_vote(&mut self) -> Result<Option<Vote<MemNodeId>>, StorageError<MemNodeId>> {
-        Ok(*self.vote.read().await)
-    }
-
     async fn save_committed(&mut self, committed: Option<LogId<MemNodeId>>) -> Result<(), StorageError<MemNodeId>> {
         tracing::debug!(?committed, "save_committed");
         let mut c = self.committed.write().await;

stores/rocksstore/src/lib.rs

@@ -267,6 +267,10 @@ impl RaftLogReader<TypeConfig> for RocksLogStore {
         }
         Ok(res)
     }
+
+    async fn read_vote(&mut self) -> Result<Option<Vote<RocksNodeId>>, StorageError<RocksNodeId>> {
+        self.get_meta::<meta::Vote>()
+    }
 }
 
 impl RaftSnapshotBuilder<TypeConfig> for RocksStateMachine {
@@ -346,10 +350,6 @@ impl RaftLogStorage<TypeConfig> for RocksLogStore {
         Ok(())
     }
 
-    async fn read_vote(&mut self) -> Result<Option<Vote<RocksNodeId>>, StorageError<RocksNodeId>> {
-        self.get_meta::<meta::Vote>()
-    }
-
     async fn get_log_reader(&mut self) -> Self::LogReader {
         self.clone()
     }

stores/sledstore/src/lib.rs

@@ -423,6 +423,10 @@ impl RaftLogReader<TypeConfig> for Arc<SledStore> {
             .collect();
         logs
     }
+
+    async fn read_vote(&mut self) -> Result<Option<Vote<ExampleNodeId>>, StorageError<ExampleNodeId>> {
+        self.get_vote_()
+    }
 }
 
 impl RaftSnapshotBuilder<TypeConfig> for Arc<SledStore> {
@@ -503,10 +507,6 @@ impl RaftLogStorage<TypeConfig> for Arc<SledStore> {
         self.set_vote_(vote).await
     }
 
-    async fn read_vote(&mut self) -> Result<Option<Vote<ExampleNodeId>>, StorageError<ExampleNodeId>> {
-        self.get_vote_()
-    }
-
     async fn get_log_reader(&mut self) -> Self::LogReader {
         self.clone()
     }

tests/tests/fixtures/mod.rs

@@ -51,6 +51,7 @@ use openraft::MessageSummary;
 use openraft::RPCTypes;
 use openraft::Raft;
 use openraft::RaftLogId;
+use openraft::RaftLogReader;
 use openraft::RaftMetrics;
 use openraft::RaftState;
 use openraft::RaftTypeConfig;

tests/tests/life_cycle/t50_single_follower_restart.rs

@@ -4,6 +4,7 @@ use std::time::Duration;
 use maplit::btreeset;
 use openraft::storage::RaftLogStorage;
 use openraft::Config;
+use openraft::RaftLogReader;
 use openraft::ServerState;
 use openraft::Vote;
 

tests/tests/snapshot_streaming/t33_snapshot_delete_conflict_logs.rs

@@ -20,6 +20,7 @@ use openraft::Entry;
 use openraft::EntryPayload;
 use openraft::LogId;
 use openraft::Membership;
+use openraft::RaftLogReader;
 use openraft::RaftSnapshotBuilder;
 use openraft::ServerState;
 use openraft::SnapshotPolicy;