diff --git a/vendor/github.com/coreos/etcd/etcdserver/api/v2v3/watcher.go b/vendor/github.com/coreos/etcd/etcdserver/api/v2v3/watcher.go
new file mode 100644
index 0000000..1c2680e
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/etcdserver/api/v2v3/watcher.go
@@ -0,0 +1,140 @@
+// Copyright 2017 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 v2v3
+
+import (
+	"context"
+	"strings"
+
+	"github.com/coreos/etcd/clientv3"
+	etcdErr "github.com/coreos/etcd/error"
+	"github.com/coreos/etcd/store"
+)
+
+func (s *v2v3Store) Watch(prefix string, recursive, stream bool, sinceIndex uint64) (store.Watcher, error) {
+	ctx, cancel := context.WithCancel(s.ctx)
+	wch := s.c.Watch(
+		ctx,
+		// TODO: very pricey; use a single store-wide watch in future
+		s.pfx,
+		clientv3.WithPrefix(),
+		clientv3.WithRev(int64(sinceIndex)),
+		clientv3.WithCreatedNotify(),
+		clientv3.WithPrevKV())
+	resp, ok := <-wch
+	if err := resp.Err(); err != nil || !ok {
+		cancel()
+		return nil, etcdErr.NewError(etcdErr.EcodeRaftInternal, prefix, 0)
+	}
+
+	evc, donec := make(chan *store.Event), make(chan struct{})
+	go func() {
+		defer func() {
+			close(evc)
+			close(donec)
+		}()
+		for resp := range wch {
+			for _, ev := range s.mkV2Events(resp) {
+				k := ev.Node.Key
+				if recursive {
+					if !strings.HasPrefix(k, prefix) {
+						continue
+					}
+					// accept events on hidden keys given in prefix
+					k = strings.Replace(k, prefix, "/", 1)
+					// ignore hidden keys deeper than prefix
+					if strings.Contains(k, "/_") {
+						continue
+					}
+				}
+				if !recursive && k != prefix {
+					continue
+				}
+				select {
+				case evc <- ev:
+				case <-ctx.Done():
+					return
+				}
+				if !stream {
+					return
+				}
+			}
+		}
+	}()
+
+	return &v2v3Watcher{
+		startRev: resp.Header.Revision,
+		evc:      evc,
+		donec:    donec,
+		cancel:   cancel,
+	}, nil
+}
+
+func (s *v2v3Store) mkV2Events(wr clientv3.WatchResponse) (evs []*store.Event) {
+	ak := s.mkActionKey()
+	for _, rev := range mkRevs(wr) {
+		var act, key *clientv3.Event
+		for _, ev := range rev {
+			if string(ev.Kv.Key) == ak {
+				act = ev
+			} else if key != nil && len(key.Kv.Key) < len(ev.Kv.Key) {
+				// use longest key to ignore intermediate new
+				// directories from Create.
+				key = ev
+			} else if key == nil {
+				key = ev
+			}
+		}
+		v2ev := &store.Event{
+			Action:    string(act.Kv.Value),
+			Node:      s.mkV2Node(key.Kv),
+			PrevNode:  s.mkV2Node(key.PrevKv),
+			EtcdIndex: mkV2Rev(wr.Header.Revision),
+		}
+		evs = append(evs, v2ev)
+	}
+	return evs
+}
+
+func mkRevs(wr clientv3.WatchResponse) (revs [][]*clientv3.Event) {
+	var curRev []*clientv3.Event
+	for _, ev := range wr.Events {
+		if curRev != nil && ev.Kv.ModRevision != curRev[0].Kv.ModRevision {
+			revs = append(revs, curRev)
+			curRev = nil
+		}
+		curRev = append(curRev, ev)
+	}
+	if curRev != nil {
+		revs = append(revs, curRev)
+	}
+	return revs
+}
+
+type v2v3Watcher struct {
+	startRev int64
+	evc      chan *store.Event
+	donec    chan struct{}
+	cancel   context.CancelFunc
+}
+
+func (w *v2v3Watcher) StartIndex() uint64 { return mkV2Rev(w.startRev) }
+
+func (w *v2v3Watcher) Remove() {
+	w.cancel()
+	<-w.donec
+}
+
+func (w *v2v3Watcher) EventChan() chan *store.Event { return w.evc }