Merge pull request #3114 from yichengq/clean-raft-init

etcdserver: clean up start and stop logic of raft

etcdserver/raft.go

@@ -108,10 +108,19 @@ type raftNode struct {
 	done    chan struct{}
 }
 
-func (r *raftNode) run() {
+// start prepares and starts raftNode in a new goroutine. It is no longer safe
+// to modify the fields after it has been started.
+// TODO: Ideally raftNode should get rid of the passed in server structure.
+func (r *raftNode) start(s *EtcdServer) {
+	r.s = s
+	r.applyc = make(chan apply)
+	r.stopped = make(chan struct{})
+	r.done = make(chan struct{})
+
+	go func() {
 		var syncC <-chan time.Time
 
-	defer r.stop()
+		defer r.onStop()
 		for {
 			select {
 			case <-r.ticker:
@@ -169,6 +178,7 @@ func (r *raftNode) run() {
 				return
 			}
 		}
+	}()
 }
 
 func (r *raftNode) apply() chan apply {
@@ -176,6 +186,11 @@ func (r *raftNode) apply() chan apply {
 }
 
 func (r *raftNode) stop() {
+	r.stopped <- struct{}{}
+	<-r.done
+}
+
+func (r *raftNode) onStop() {
 	r.Stop()
 	r.transport.Stop()
 	if err := r.storage.Close(); err != nil {

etcdserver/raft_test.go

@@ -148,15 +148,11 @@ func TestStopRaftWhenWaitingForApplyDone(t *testing.T) {
 	n := newReadyNode()
 	r := raftNode{
 		Node:        n,
-		applyc:      make(chan apply),
 		storage:     &storageRecorder{},
 		raftStorage: raft.NewMemoryStorage(),
 		transport:   &nopTransporter{},
-		stopped:     make(chan struct{}),
-		done:        make(chan struct{}),
 	}
-	r.s = &EtcdServer{r: r}
-	go r.run()
+	r.start(&EtcdServer{r: r})
 	n.readyc <- raft.Ready{}
 	select {
 	case <-r.applyc:

etcdserver/server.go

@@ -413,15 +413,9 @@ func (s *EtcdServer) run() {
 	confState := snap.Metadata.ConfState
 	snapi := snap.Metadata.Index
 	appliedi := snapi
-	// TODO: get rid of the raft initialization in etcd server
-	s.r.s = s
-	s.r.applyc = make(chan apply)
-	s.r.stopped = make(chan struct{})
-	s.r.done = make(chan struct{})
-	go s.r.run()
+	s.r.start(s)
 	defer func() {
-		s.r.stopped <- struct{}{}
-		<-s.r.done
+		s.r.stop()
 		close(s.done)
 	}()