Merge pull request #4487 from gyuho/leader_api

etcdserver: include IsLeader in etcdserverpb.Member

clientv3/cluster.go

@@ -23,6 +23,7 @@ import (
 )
 
 type (
+	Member               pb.Member
 	MemberListResponse   pb.MemberListResponse
 	MemberAddResponse    pb.MemberAddResponse
 	MemberRemoveResponse pb.MemberRemoveResponse
@@ -33,6 +34,9 @@ type Cluster interface {
 	// List lists the current cluster membership.
 	MemberList(ctx context.Context) (*MemberListResponse, error)
 
+	// Leader returns the current leader member.
+	MemberLeader(ctx context.Context) (*Member, error)
+
 	// MemberAdd adds a new member into the cluster.
 	MemberAdd(ctx context.Context, peerAddrs []string) (*MemberAddResponse, error)
 
@@ -131,6 +135,19 @@ func (c *cluster) MemberList(ctx context.Context) (*MemberListResponse, error) {
 	}
 }
 
+func (c *cluster) MemberLeader(ctx context.Context) (*Member, error) {
+	resp, err := c.MemberList(ctx)
+	if err != nil {
+		return nil, err
+	}
+	for _, m := range resp.Members {
+		if m.IsLeader {
+			return (*Member)(m), nil
+		}
+	}
+	return nil, nil
+}
+
 func (c *cluster) getRemote() pb.ClusterClient {
 	c.mu.Lock()
 	defer c.mu.Unlock()

etcdserver/api/v3rpc/member.go

@@ -59,7 +59,7 @@ func (cs *ClusterServer) MemberAdd(ctx context.Context, r *pb.MemberAddRequest)
 
 	return &pb.MemberAddResponse{
 		Header: cs.header(),
-		Member: &pb.Member{ID: uint64(m.ID), PeerURLs: m.PeerURLs},
+		Member: &pb.Member{ID: uint64(m.ID), IsLeader: m.ID == cs.server.Leader(), PeerURLs: m.PeerURLs},
 	}, nil
 }
 
@@ -103,6 +103,7 @@ func (cs *ClusterServer) MemberList(ctx context.Context, r *pb.MemberListRequest
 		protoMembs[i] = &pb.Member{
 			Name:       membs[i].Name,
 			ID:         uint64(membs[i].ID),
+			IsLeader:   membs[i].ID == cs.server.Leader(),
 			PeerURLs:   membs[i].PeerURLs,
 			ClientURLs: membs[i].ClientURLs,
 		}

etcdserver/etcdserverpb/rpc.pb.go

@@ -994,10 +994,11 @@ type Member struct {
 	ID uint64 `protobuf:"varint,1,opt,name=ID,proto3" json:"ID,omitempty"`
 	// If the member is not started, name will be an empty string.
 	Name     string   `protobuf:"bytes,2,opt,name=name,proto3" json:"name,omitempty"`
-	PeerURLs []string `protobuf:"bytes,3,rep,name=peerURLs" json:"peerURLs,omitempty"`
+	IsLeader bool     `protobuf:"varint,3,opt,name=IsLeader,proto3" json:"IsLeader,omitempty"`
+	PeerURLs []string `protobuf:"bytes,4,rep,name=peerURLs" json:"peerURLs,omitempty"`
 	// If the member is not started, client_URLs will be an zero length
 	// string array.
-	ClientURLs []string `protobuf:"bytes,4,rep,name=clientURLs" json:"clientURLs,omitempty"`
+	ClientURLs []string `protobuf:"bytes,5,rep,name=clientURLs" json:"clientURLs,omitempty"`
 }
 
 func (m *Member) Reset()         { *m = Member{} }
@@ -2868,9 +2869,19 @@ func (m *Member) MarshalTo(data []byte) (int, error) {
 		i = encodeVarintRpc(data, i, uint64(len(m.Name)))
 		i += copy(data[i:], m.Name)
 	}
+	if m.IsLeader {
+		data[i] = 0x18
+		i++
+		if m.IsLeader {
+			data[i] = 1
+		} else {
+			data[i] = 0
+		}
+		i++
+	}
 	if len(m.PeerURLs) > 0 {
 		for _, s := range m.PeerURLs {
-			data[i] = 0x1a
+			data[i] = 0x22
 			i++
 			l = len(s)
 			for l >= 1<<7 {
@@ -2885,7 +2896,7 @@ func (m *Member) MarshalTo(data []byte) (int, error) {
 	}
 	if len(m.ClientURLs) > 0 {
 		for _, s := range m.ClientURLs {
-			data[i] = 0x22
+			data[i] = 0x2a
 			i++
 			l = len(s)
 			for l >= 1<<7 {
@@ -3668,6 +3679,9 @@ func (m *Member) Size() (n int) {
 	if l > 0 {
 		n += 1 + l + sovRpc(uint64(l))
 	}
+	if m.IsLeader {
+		n += 2
+	}
 	if len(m.PeerURLs) > 0 {
 		for _, s := range m.PeerURLs {
 			l = len(s)
@@ -6859,6 +6873,26 @@ func (m *Member) Unmarshal(data []byte) error {
 			m.Name = string(data[iNdEx:postIndex])
 			iNdEx = postIndex
 		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field IsLeader", wireType)
+			}
+			var v int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowRpc
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				v |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			m.IsLeader = bool(v != 0)
+		case 4:
 			if wireType != 2 {
 				return fmt.Errorf("proto: wrong wireType = %d for field PeerURLs", wireType)
 			}
@@ -6887,7 +6921,7 @@ func (m *Member) Unmarshal(data []byte) error {
 			}
 			m.PeerURLs = append(m.PeerURLs, string(data[iNdEx:postIndex]))
 			iNdEx = postIndex
-		case 4:
+		case 5:
 			if wireType != 2 {
 				return fmt.Errorf("proto: wrong wireType = %d for field ClientURLs", wireType)
 			}

etcdserver/etcdserverpb/rpc.proto

@@ -323,10 +323,11 @@ message Member {
   uint64 ID = 1;
   // If the member is not started, name will be an empty string.
   string name = 2;
-  repeated string peerURLs = 3;
+  bool IsLeader = 3;
+  repeated string peerURLs = 4;
   // If the member is not started, client_URLs will be an zero length
   // string array.
-  repeated string clientURLs = 4;
+  repeated string clientURLs = 5;
 }
 
 message MemberAddRequest {