[VOL-4291] Rw-core updates for gRPC migration

Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/coreos/etcd/compactor/compactor.go b/vendor/github.com/coreos/etcd/compactor/compactor.go
new file mode 100644
index 0000000..8100b69
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/compactor/compactor.go
@@ -0,0 +1,66 @@
+// Copyright 2016 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 compactor
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
+
+	"github.com/coreos/pkg/capnslog"
+)
+
+var (
+	plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "compactor")
+)
+
+const (
+	ModePeriodic = "periodic"
+	ModeRevision = "revision"
+)
+
+// Compactor purges old log from the storage periodically.
+type Compactor interface {
+	// Run starts the main loop of the compactor in background.
+	// Use Stop() to halt the loop and release the resource.
+	Run()
+	// Stop halts the main loop of the compactor.
+	Stop()
+	// Pause temporally suspend the compactor not to run compaction. Resume() to unpose.
+	Pause()
+	// Resume restarts the compactor suspended by Pause().
+	Resume()
+}
+
+type Compactable interface {
+	Compact(ctx context.Context, r *pb.CompactionRequest) (*pb.CompactionResponse, error)
+}
+
+type RevGetter interface {
+	Rev() int64
+}
+
+func New(mode string, retention time.Duration, rg RevGetter, c Compactable) (Compactor, error) {
+	switch mode {
+	case ModePeriodic:
+		return NewPeriodic(retention, rg, c), nil
+	case ModeRevision:
+		return NewRevision(int64(retention), rg, c), nil
+	default:
+		return nil, fmt.Errorf("unsupported compaction mode %s", mode)
+	}
+}