[VOL-4291] Rw-core updates for gRPC migration
Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/coreos/etcd/etcdserver/snapshot_merge.go b/vendor/github.com/coreos/etcd/etcdserver/snapshot_merge.go
new file mode 100644
index 0000000..928aa95
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/etcdserver/snapshot_merge.go
@@ -0,0 +1,73 @@
+// Copyright 2015 The etcd Authors
+//
+// 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 etcdserver
+
+import (
+ "io"
+
+ "github.com/coreos/etcd/mvcc/backend"
+ "github.com/coreos/etcd/raft/raftpb"
+ "github.com/coreos/etcd/snap"
+)
+
+// createMergedSnapshotMessage creates a snapshot message that contains: raft status (term, conf),
+// a snapshot of v2 store inside raft.Snapshot as []byte, a snapshot of v3 KV in the top level message
+// as ReadCloser.
+func (s *EtcdServer) createMergedSnapshotMessage(m raftpb.Message, snapt, snapi uint64, confState raftpb.ConfState) snap.Message {
+ // get a snapshot of v2 store as []byte
+ clone := s.store.Clone()
+ d, err := clone.SaveNoCopy()
+ if err != nil {
+ plog.Panicf("store save should never fail: %v", err)
+ }
+
+ // commit kv to write metadata(for example: consistent index).
+ s.KV().Commit()
+ dbsnap := s.be.Snapshot()
+ // get a snapshot of v3 KV as readCloser
+ rc := newSnapshotReaderCloser(dbsnap)
+
+ // put the []byte snapshot of store into raft snapshot and return the merged snapshot with
+ // KV readCloser snapshot.
+ snapshot := raftpb.Snapshot{
+ Metadata: raftpb.SnapshotMetadata{
+ Index: snapi,
+ Term: snapt,
+ ConfState: confState,
+ },
+ Data: d,
+ }
+ m.Snapshot = snapshot
+
+ return *snap.NewMessage(m, rc, dbsnap.Size())
+}
+
+func newSnapshotReaderCloser(snapshot backend.Snapshot) io.ReadCloser {
+ pr, pw := io.Pipe()
+ go func() {
+ n, err := snapshot.WriteTo(pw)
+ if err == nil {
+ plog.Infof("wrote database snapshot out [total bytes: %d]", n)
+ } else {
+ plog.Warningf("failed to write database snapshot out [written bytes: %d]: %v", n, err)
+ }
+ pw.CloseWithError(err)
+ err = snapshot.Close()
+ if err != nil {
+ plog.Panicf("failed to close database snapshot: %v", err)
+ }
+ }()
+ return pr
+}