Change: EffectiveMembership.log_id to Option<LogId>

example-raft-kv/src/store/mod.rs

@@ -72,6 +72,7 @@ pub struct ExampleSnapshot {
 pub struct ExampleStateMachine {
     pub last_applied_log: Option<LogId<ExampleNodeId>>,
 
+    // TODO: it should not be Option.
     pub last_membership: Option<EffectiveMembership<ExampleTypeConfig>>,
 
     /// Application data.
@@ -287,7 +288,7 @@ impl RaftStorage<ExampleTypeConfig> for Arc<ExampleStore> {
                     }
                 },
                 EntryPayload::Membership(ref mem) => {
-                    sm.last_membership = Some(EffectiveMembership::new(entry.log_id, mem.clone()));
+                    sm.last_membership = Some(EffectiveMembership::new(Some(entry.log_id), mem.clone()));
                     res.push(ExampleResponse { value: None })
                 }
             };

memstore/src/lib.rs

@@ -343,7 +343,7 @@ impl RaftStorage<Config> for Arc<MemStore> {
                     res.push(ClientResponse(previous));
                 }
                 EntryPayload::Membership(ref mem) => {
-                    sm.last_membership = Some(EffectiveMembership::new(entry.log_id, mem.clone()));
+                    sm.last_membership = Some(EffectiveMembership::new(Some(entry.log_id), mem.clone()));
                     res.push(ClientResponse(None))
                 }
             };

openraft/src/core/admin.rs

@@ -164,7 +164,7 @@ impl<'a, C: RaftTypeConfig, N: RaftNetworkFactory<C>, S: RaftStorage<C>> LeaderS
     fn has_pending_config(&self) -> bool {
         // The last membership config is not committed yet.
         // Can not process the next one.
-        self.core.committed < Some(self.core.effective_membership.log_id)
+        self.core.committed < self.core.effective_membership.log_id
     }
 
     #[tracing::instrument(level = "debug", skip(self, tx))]
@@ -187,7 +187,8 @@ impl<'a, C: RaftTypeConfig, N: RaftNetworkFactory<C>, S: RaftStorage<C>> LeaderS
         if self.has_pending_config() {
             let _ = tx.send(Err(ClientWriteError::ChangeMembershipError(
                 ChangeMembershipError::InProgress(InProgress {
-                    membership_log_id: self.core.effective_membership.log_id,
+                    // has_pending_config() implies an existing membership log.
+                    membership_log_id: self.core.effective_membership.log_id.unwrap(),
                 }),
             )));
             return Ok(());

openraft/src/core/append_entries.rs

@@ -299,7 +299,7 @@ impl<C: RaftTypeConfig, N: RaftNetworkFactory<C>, S: RaftStorage<C>> RaftCore<C,
         let last_conf_change = entries
             .iter()
             .filter_map(|ent| match &ent.payload {
-                EntryPayload::Membership(conf) => Some(EffectiveMembership::new(ent.log_id, conf.clone())),
+                EntryPayload::Membership(conf) => Some(EffectiveMembership::new(Some(ent.log_id), conf.clone())),
                 _ => None,
             })
             .last();

openraft/src/core/mod.rs

@@ -77,8 +77,7 @@ use crate::Update;
 #[derive(Clone, Default, Eq, Serialize, Deserialize)]
 pub struct EffectiveMembership<C: RaftTypeConfig> {
     /// The id of the log that applies this membership config
-    /// TODO: this `log_id` should be an `Option<LogId>`.
-    pub log_id: LogId<C::NodeId>,
+    pub log_id: Option<LogId<C::NodeId>>,
 
     pub membership: Membership<C::NodeId>,
 
@@ -103,7 +102,7 @@ impl<C: RaftTypeConfig> PartialEq for EffectiveMembership<C> {
 }
 
 impl<C: RaftTypeConfig> EffectiveMembership<C> {
-    pub fn new(log_id: LogId<C::NodeId>, membership: Membership<C::NodeId>) -> Self {
+    pub fn new(log_id: Option<LogId<C::NodeId>>, membership: Membership<C::NodeId>) -> Self {
         let all_members = membership.build_member_ids();
         Self {
             log_id,
@@ -147,7 +146,7 @@ impl<C: RaftTypeConfig> EffectiveMembership<C> {
 
 impl<C: RaftTypeConfig> MessageSummary for EffectiveMembership<C> {
     fn summary(&self) -> String {
-        format!("{{log_id:{} membership:{}}}", self.log_id, self.membership.summary())
+        format!("{{log_id:{:?} membership:{}}}", self.log_id, self.membership.summary())
     }
 }
 
@@ -612,7 +611,7 @@ impl<C: RaftTypeConfig, N: RaftNetworkFactory<C>, S: RaftStorage<C>> RaftCore<C,
         self.last_log_id = Some(log_id);
 
         if let EntryPayload::Membership(mem) = &entry.payload {
-            self.effective_membership = Arc::new(EffectiveMembership::new(entry.log_id, mem.clone()));
+            self.effective_membership = Arc::new(EffectiveMembership::new(Some(entry.log_id), mem.clone()));
         }
 
         Ok(entry)

openraft/src/metrics_wait_test.rs

@@ -90,7 +90,7 @@ async fn test_wait() -> anyhow::Result<()> {
             sleep(Duration::from_millis(10)).await;
             let mut update = init.clone();
             update.membership_config = Arc::new(EffectiveMembership::new(
-                LogId::default(),
+                None,
                 Membership::new(vec![btreeset! {1,2}], None),
             ));
             let rst = tx.send(update);
@@ -113,7 +113,7 @@ async fn test_wait() -> anyhow::Result<()> {
             sleep(Duration::from_millis(10)).await;
             let mut update = init.clone();
             update.membership_config = Arc::new(EffectiveMembership::new(
-                LogId::default(),
+                None,
                 Membership::new(vec![btreeset! {}, btreeset! {1,2}], None),
             ));
             let rst = tx.send(update);
@@ -205,7 +205,7 @@ fn init_wait_test<C: RaftTypeConfig>() -> (RaftMetrics<C>, Wait<C>, watch::Sende
         last_applied: None,
         current_leader: None,
         membership_config: Arc::new(EffectiveMembership::new(
-            LogId::default(),
+            None,
             Membership::new(vec![btreeset! {}], None),
         )),
 

openraft/src/storage.rs

@@ -196,12 +196,12 @@ where C: RaftTypeConfig
     async fn get_membership(&mut self) -> Result<Option<EffectiveMembership<C>>, StorageError<C::NodeId>> {
         let (_, sm_mem) = self.last_applied_state().await?;
 
-        let sm_mem_index = match &sm_mem {
+        let sm_mem_next_index = match &sm_mem {
             None => 0,
-            Some(mem) => mem.log_id.index,
+            Some(mem) => mem.log_id.next_index(),
         };
 
-        let log_mem = self.last_membership_in_log(sm_mem_index + 1).await?;
+        let log_mem = self.last_membership_in_log(sm_mem_next_index).await?;
 
         if log_mem.is_some() {
             return Ok(log_mem);
@@ -230,7 +230,7 @@ where C: RaftTypeConfig
 
             for ent in entries.iter().rev() {
                 if let EntryPayload::Membership(ref mem) = ent.payload {
-                    return Ok(Some(EffectiveMembership::new(ent.log_id, mem.clone())));
+                    return Ok(Some(EffectiveMembership::new(Some(ent.log_id), mem.clone())));
                 }
             }
 

openraft/src/testing/suite.rs

@@ -638,7 +638,7 @@ where
             assert_eq!(Some(LogId::new(LeaderId::new(1, NODE_ID.into()), 3)), applied);
             assert_eq!(
                 Some(EffectiveMembership::new(
-                    LogId::new(LeaderId::new(1, NODE_ID.into()), 3),
+                    Some(LogId::new(LeaderId::new(1, NODE_ID.into()), 3)),
                     Membership::new(vec![btreeset! {1,2}], None)
                 )),
                 membership
@@ -658,7 +658,7 @@ where
             assert_eq!(Some(LogId::new(LeaderId::new(1, NODE_ID.into()), 5)), applied);
             assert_eq!(
                 Some(EffectiveMembership::new(
-                    LogId::new(LeaderId::new(1, NODE_ID.into()), 3),
+                    Some(LogId::new(LeaderId::new(1, NODE_ID.into()), 3)),
                     Membership::new(vec![btreeset! {1,2}], None)
                 )),
                 membership

openraft/tests/initialization.rs

@@ -88,7 +88,7 @@ async fn initialization() -> Result<()> {
         let sm_mem = sto.last_applied_state().await?.1;
         assert_eq!(
             Some(EffectiveMembership::new(
-                LogId::new(LeaderId::new(0, 0), 0),
+                Some(LogId::new(LeaderId::new(0, 0), 0)),
                 Membership::new(vec![btreeset! {0,1,2}], None)
             )),
             sm_mem

openraft/tests/state_machine/t20_state_machine_apply_membership.rs

@@ -50,7 +50,7 @@ async fn state_machine_apply_membership() -> Result<()> {
         let mut sto = router.get_storage_handle(&i)?;
         assert_eq!(
             Some(EffectiveMembership::new(
-                LogId::new(LeaderId::new(0, 0), 0),
+                Some(LogId::new(LeaderId::new(0, 0), 0)),
                 Membership::new(vec![btreeset! {0}], None)
             )),
             sto.last_applied_state().await?.1
@@ -102,7 +102,7 @@ async fn state_machine_apply_membership() -> Result<()> {
         let (_, last_membership) = sto.last_applied_state().await?;
         assert_eq!(
             Some(EffectiveMembership::new(
-                LogId::new(LeaderId::new(1, 0), log_index),
+                Some(LogId::new(LeaderId::new(1, 0), log_index)),
                 Membership::new(vec![btreeset! {0, 1, 2}], Some(btreeset! {3,4}))
             )),
             last_membership