raft: support to do multiple proposals in one message

raft.go

@@ -300,10 +300,13 @@ func (r *raft) reset(term uint64) {
 	r.pendingConf = false
 }
 
-func (r *raft) appendEntry(e pb.Entry) {
-	e.Term = r.Term
-	e.Index = r.raftLog.lastIndex() + 1
-	r.raftLog.append(e)
+func (r *raft) appendEntry(es ...pb.Entry) {
+	li := r.raftLog.lastIndex()
+	for i := range es {
+		es[i].Term = r.Term
+		es[i].Index = li + 1 + uint64(i)
+	}
+	r.raftLog.append(es...)
 	r.prs[r.id].update(r.raftLog.lastIndex())
 	r.maybeCommit()
 }
@@ -446,17 +449,18 @@ func stepLeader(r *raft, m pb.Message) {
 	case pb.MsgBeat:
 		r.bcastHeartbeat()
 	case pb.MsgProp:
-		if len(m.Entries) != 1 {
-			panic("unexpected length(entries) of a MsgProp")
+		if len(m.Entries) == 0 {
+			log.Panicf("raft: %x stepped empty MsgProp", r.id)
 		}
-		e := m.Entries[0]
-		if e.Type == pb.EntryConfChange {
-			if r.pendingConf {
-				return
+		for i, e := range m.Entries {
+			if e.Type == pb.EntryConfChange {
+				if r.pendingConf {
+					m.Entries[i] = pb.Entry{Type: pb.EntryNormal}
+				}
+				r.pendingConf = true
 			}
-			r.pendingConf = true
 		}
-		r.appendEntry(e)
+		r.appendEntry(m.Entries...)
 		r.bcastAppend()
 	case pb.MsgAppResp:
 		if m.Reject {

raft_test.go

@@ -1245,8 +1245,8 @@ func TestStepConfig(t *testing.T) {
 }
 
 // TestStepIgnoreConfig tests that if raft step the second msgProp in
-// EntryConfChange type when the first one is uncommitted, the node will deny
-// the proposal and keep its original state.
+// EntryConfChange type when the first one is uncommitted, the node will set
+// the proposal to noop and keep its original state.
 func TestStepIgnoreConfig(t *testing.T) {
 	// a raft that cannot make progress
 	r := newRaft(1, []uint64{1, 2}, 10, 1, NewMemoryStorage())
@@ -1256,8 +1256,9 @@ func TestStepIgnoreConfig(t *testing.T) {
 	index := r.raftLog.lastIndex()
 	pendingConf := r.pendingConf
 	r.Step(pb.Message{From: 1, To: 1, Type: pb.MsgProp, Entries: []pb.Entry{{Type: pb.EntryConfChange}}})
-	if g := r.raftLog.lastIndex(); g != index {
-		t.Errorf("index = %d, want %d", g, index)
+	wents := []pb.Entry{{Type: pb.EntryNormal, Term: 1, Index: 3, Data: nil}}
+	if ents := r.raftLog.entries(index + 1); !reflect.DeepEqual(ents, wents) {
+		t.Errorf("ents = %+v, want %+v", ents, wents)
 	}
 	if r.pendingConf != pendingConf {
 		t.Errorf("pendingConf = %v, want %v", r.pendingConf, pendingConf)