etcd: update conf when apply the confChange entry

etcdserver/server.go

@@ -395,7 +395,7 @@ func (s *EtcdServer) run() {
 	// snapi indicates the index of the last submitted snapshot request
 	snapi := snap.Metadata.Index
 	appliedi := snap.Metadata.Index
-	nodes := snap.Metadata.ConfState.Nodes
+	confState := &snap.Metadata.ConfState
 
 	defer func() {
 		s.node.Stop()
@@ -412,7 +412,6 @@ func (s *EtcdServer) run() {
 		case rd := <-s.node.Ready():
 			if rd.SoftState != nil {
 				atomic.StoreUint64(&s.raftLead, rd.SoftState.Lead)
-				nodes = rd.SoftState.Nodes
 				if rd.RaftState == raft.StateLeader {
 					syncC = s.SyncTicker
 				} else {
@@ -459,7 +458,7 @@ func (s *EtcdServer) run() {
 					ents = rd.CommittedEntries[appliedi+1-firsti:]
 				}
 				if len(ents) > 0 {
-					if appliedi, shouldstop = s.apply(ents); shouldstop {
+					if appliedi, shouldstop = s.apply(ents, confState); shouldstop {
 						return
 					}
 				}
@@ -469,7 +468,7 @@ func (s *EtcdServer) run() {
 
 			if appliedi-snapi > s.snapCount {
 				log.Printf("etcdserver: start to snapshot (applied: %d, lastsnap: %d)", appliedi, snapi)
-				s.snapshot(appliedi, nodes)
+				s.snapshot(appliedi, confState)
 				snapi = appliedi
 			}
 		case <-syncC:
@@ -701,7 +700,7 @@ func getExpirationTime(r *pb.Request) time.Time {
 // apply takes entries received from Raft (after it has been committed) and
 // applies them to the current state of the EtcdServer.
 // The given entries should not be empty.
-func (s *EtcdServer) apply(es []raftpb.Entry) (uint64, bool) {
+func (s *EtcdServer) apply(es []raftpb.Entry, confState *raftpb.ConfState) (uint64, bool) {
 	var applied uint64
 	for i := range es {
 		e := es[i]
@@ -713,7 +712,7 @@ func (s *EtcdServer) apply(es []raftpb.Entry) (uint64, bool) {
 		case raftpb.EntryConfChange:
 			var cc raftpb.ConfChange
 			pbutil.MustUnmarshal(&cc, e.Data)
-			shouldstop, err := s.applyConfChange(cc)
+			shouldstop, err := s.applyConfChange(cc, confState)
 			s.w.Trigger(cc.ID, err)
 			if shouldstop {
 				return applied, true
@@ -779,13 +778,13 @@ func (s *EtcdServer) applyRequest(r pb.Request) Response {
 
 // applyConfChange applies a ConfChange to the server. It is only
 // invoked with a ConfChange that has already passed through Raft
-func (s *EtcdServer) applyConfChange(cc raftpb.ConfChange) (bool, error) {
+func (s *EtcdServer) applyConfChange(cc raftpb.ConfChange, confState *raftpb.ConfState) (bool, error) {
 	if err := s.Cluster.ValidateConfigurationChange(cc); err != nil {
 		cc.NodeID = raft.None
 		s.node.ApplyConfChange(cc)
 		return false, err
 	}
-	s.node.ApplyConfChange(cc)
+	confState = s.node.ApplyConfChange(cc)
 	switch cc.Type {
 	case raftpb.ConfChangeAddNode:
 		m := new(Member)
@@ -833,14 +832,14 @@ func (s *EtcdServer) applyConfChange(cc raftpb.ConfChange) (bool, error) {
 }
 
 // TODO: non-blocking snapshot
-func (s *EtcdServer) snapshot(snapi uint64, snapnodes []uint64) {
+func (s *EtcdServer) snapshot(snapi uint64, confState *raftpb.ConfState) {
 	d, err := s.store.Save()
 	// TODO: current store will never fail to do a snapshot
 	// what should we do if the store might fail?
 	if err != nil {
 		log.Panicf("etcdserver: store save should never fail: %v", err)
 	}
-	err = s.raftStorage.Compact(snapi, &raftpb.ConfState{Nodes: snapnodes}, d)
+	err = s.raftStorage.Compact(snapi, confState, d)
 	if err != nil {
 		// the snapshot was done asynchronously with the progress of raft.
 		// raft might have already got a newer snapshot and called compact.

etcdserver/server_test.go

@@ -475,7 +475,7 @@ func TestApplyConfChangeError(t *testing.T) {
 			node:    n,
 			Cluster: cl,
 		}
-		_, err := srv.applyConfChange(tt.cc)
+		_, err := srv.applyConfChange(tt.cc, nil)
 		if err != tt.werr {
 			t.Errorf("#%d: applyConfChange error = %v, want %v", i, err, tt.werr)
 		}
@@ -509,7 +509,7 @@ func TestApplyConfChangeShouldStop(t *testing.T) {
 		NodeID: 2,
 	}
 	// remove non-local member
-	shouldStop, err := srv.applyConfChange(cc)
+	shouldStop, err := srv.applyConfChange(cc, nil)
 	if err != nil {
 		t.Fatalf("unexpected error %v", err)
 	}
@@ -519,7 +519,7 @@ func TestApplyConfChangeShouldStop(t *testing.T) {
 
 	// remove local member
 	cc.NodeID = 1
-	shouldStop, err = srv.applyConfChange(cc)
+	shouldStop, err = srv.applyConfChange(cc, nil)
 	if err != nil {
 		t.Fatalf("unexpected error %v", err)
 	}
@@ -917,7 +917,7 @@ func TestSnapshot(t *testing.T) {
 		raftStorage: s,
 	}
 
-	srv.snapshot(1, []uint64{1})
+	srv.snapshot(1, &raftpb.ConfState{Nodes: []uint64{1}})
 	gaction := st.Action()
 	if len(gaction) != 1 {
 		t.Fatalf("len(action) = %d, want 1", len(gaction))