From 8368e6a992a61bb79df62334d0e1ffc171d57054 Mon Sep 17 00:00:00 2001
From: Xiang Li <xiangli.cs@gmail.com>
Date: Wed, 13 Jul 2016 16:02:49 -0700
Subject: [PATCH] embed: only get initial cluster setting if the member is not
 init

---
 embed/etcd.go | 15 +++++++++++----
 embed/util.go | 30 ++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 4 deletions(-)
 create mode 100644 embed/util.go

diff --git a/embed/etcd.go b/embed/etcd.go
index d38d6dad6..2f7696eff 100644
--- a/embed/etcd.go
+++ b/embed/etcd.go
@@ -26,6 +26,7 @@ import (
 	"github.com/coreos/etcd/pkg/cors"
 	runtimeutil "github.com/coreos/etcd/pkg/runtime"
 	"github.com/coreos/etcd/pkg/transport"
+	"github.com/coreos/etcd/pkg/types"
 	"github.com/coreos/etcd/rafthttp"
 	"github.com/coreos/pkg/capnslog"
 )
@@ -81,10 +82,16 @@ func StartEtcd(inCfg *Config) (e *Etcd, err error) {
 		e.Clients = append(e.Clients, sctx.l)
 	}
 
-	urlsmap, token, uerr := cfg.PeerURLsMapAndToken("etcd")
-	if uerr != nil {
-		err = fmt.Errorf("error setting up initial cluster: %v", uerr)
-		return
+	var (
+		urlsmap types.URLsMap
+		token   string
+	)
+
+	if !isMemberInitialized(cfg) {
+		urlsmap, token, err = cfg.PeerURLsMapAndToken("etcd")
+		if err != nil {
+			return nil, fmt.Errorf("error setting up initial cluster: %v", err)
+		}
 	}
 
 	srvcfg := &etcdserver.ServerConfig{
diff --git a/embed/util.go b/embed/util.go
new file mode 100644
index 000000000..39cf0ccdb
--- /dev/null
+++ b/embed/util.go
@@ -0,0 +1,30 @@
+// 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 embed
+
+import (
+	"path"
+
+	"github.com/coreos/etcd/wal"
+)
+
+func isMemberInitialized(cfg *Config) bool {
+	waldir := cfg.WalDir
+	if waldir == "" {
+		waldir = path.Join(cfg.Dir, "member", "wal")
+	}
+
+	return wal.Exist(waldir)
+}