v3rpc: move Hash RPC to Maintenance service

etcdserver/api/v3rpc/header.go

@@ -0,0 +1,43 @@
+// Copyright 2016 CoreOS, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package v3rpc
+
+import (
+	"github.com/coreos/etcd/etcdserver"
+	pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
+)
+
+type header struct {
+	clusterID int64
+	memberID  int64
+	raftTimer etcdserver.RaftTimer
+	rev       func() int64
+}
+
+func newHeader(s *etcdserver.EtcdServer) header {
+	return header{
+		clusterID: int64(s.Cluster().ID()),
+		memberID:  int64(s.ID()),
+		raftTimer: s,
+		rev:       func() int64 { return s.KV().Rev() },
+	}
+}
+
+// fill populates pb.ResponseHeader using etcdserver information
+func (h *header) fill(rh *pb.ResponseHeader) {
+	rh.ClusterId = uint64(h.clusterID)
+	rh.MemberId = uint64(h.memberID)
+	rh.RaftTerm = h.raftTimer.Term()
+}

etcdserver/api/v3rpc/key.go

@@ -38,20 +38,12 @@ var (
 )
 
 type kvServer struct {
-	clusterID int64
-	memberID  int64
-	raftTimer etcdserver.RaftTimer
-
-	kv etcdserver.RaftKV
+	hdr header
+	kv  etcdserver.RaftKV
 }
 
 func NewKVServer(s *etcdserver.EtcdServer) pb.KVServer {
-	return &kvServer{
-		clusterID: int64(s.Cluster().ID()),
-		memberID:  int64(s.ID()),
-		raftTimer: s,
-		kv:        s,
-	}
+	return &kvServer{hdr: newHeader(s), kv: s}
 }
 
 func (s *kvServer) Range(ctx context.Context, r *pb.RangeRequest) (*pb.RangeResponse, error) {
@@ -67,7 +59,7 @@ func (s *kvServer) Range(ctx context.Context, r *pb.RangeRequest) (*pb.RangeResp
 	if resp.Header == nil {
 		plog.Panic("unexpected nil resp.Header")
 	}
-	s.fillInHeader(resp.Header)
+	s.hdr.fill(resp.Header)
 	return resp, err
 }
 
@@ -84,7 +76,7 @@ func (s *kvServer) Put(ctx context.Context, r *pb.PutRequest) (*pb.PutResponse,
 	if resp.Header == nil {
 		plog.Panic("unexpected nil resp.Header")
 	}
-	s.fillInHeader(resp.Header)
+	s.hdr.fill(resp.Header)
 	return resp, err
 }
 
@@ -101,7 +93,7 @@ func (s *kvServer) DeleteRange(ctx context.Context, r *pb.DeleteRangeRequest) (*
 	if resp.Header == nil {
 		plog.Panic("unexpected nil resp.Header")
 	}
-	s.fillInHeader(resp.Header)
+	s.hdr.fill(resp.Header)
 	return resp, err
 }
 
@@ -118,7 +110,7 @@ func (s *kvServer) Txn(ctx context.Context, r *pb.TxnRequest) (*pb.TxnResponse,
 	if resp.Header == nil {
 		plog.Panic("unexpected nil resp.Header")
 	}
-	s.fillInHeader(resp.Header)
+	s.hdr.fill(resp.Header)
 	return resp, err
 }
 
@@ -131,26 +123,10 @@ func (s *kvServer) Compact(ctx context.Context, r *pb.CompactionRequest) (*pb.Co
 	if resp.Header == nil {
 		plog.Panic("unexpected nil resp.Header")
 	}
-	s.fillInHeader(resp.Header)
+	s.hdr.fill(resp.Header)
 	return resp, nil
 }
 
-func (s *kvServer) Hash(ctx context.Context, r *pb.HashRequest) (*pb.HashResponse, error) {
-	resp, err := s.kv.Hash(ctx, r)
-	if err != nil {
-		return nil, togRPCError(err)
-	}
-	s.fillInHeader(resp.Header)
-	return resp, nil
-}
-
-// fillInHeader populates pb.ResponseHeader from kvServer, except Revision.
-func (s *kvServer) fillInHeader(h *pb.ResponseHeader) {
-	h.ClusterId = uint64(s.clusterID)
-	h.MemberId = uint64(s.memberID)
-	h.RaftTerm = s.raftTimer.Term()
-}
-
 func checkRangeRequest(r *pb.RangeRequest) error {
 	if len(r.Key) == 0 {
 		return rpctypes.ErrEmptyKey

etcdserver/api/v3rpc/maintenance.go

@@ -30,12 +30,13 @@ type Alarmer interface {
 }
 
 type maintenanceServer struct {
-	bg BackendGetter
-	a  Alarmer
+	bg  BackendGetter
+	a   Alarmer
+	hdr header
 }
 
 func NewMaintenanceServer(s *etcdserver.EtcdServer) pb.MaintenanceServer {
-	return &maintenanceServer{bg: s, a: s}
+	return &maintenanceServer{bg: s, a: s, hdr: newHeader(s)}
 }
 
 func (ms *maintenanceServer) Defragment(ctx context.Context, sr *pb.DefragmentRequest) (*pb.DefragmentResponse, error) {
@@ -49,6 +50,16 @@ func (ms *maintenanceServer) Defragment(ctx context.Context, sr *pb.DefragmentRe
 	return &pb.DefragmentResponse{}, nil
 }
 
+func (s *maintenanceServer) Hash(ctx context.Context, r *pb.HashRequest) (*pb.HashResponse, error) {
+	h, err := s.bg.Backend().Hash()
+	if err != nil {
+		return nil, togRPCError(err)
+	}
+	resp := &pb.HashResponse{Header: &pb.ResponseHeader{Revision: s.hdr.rev()}, Hash: h}
+	s.hdr.fill(resp.Header)
+	return resp, nil
+}
+
 func (ms *maintenanceServer) Alarm(ctx context.Context, ar *pb.AlarmRequest) (*pb.AlarmResponse, error) {
 	plog.Warningf("alarming %+v", ar)
 	return ms.a.Alarm(ctx, ar)