volume server get notified of leader change

weed/storage/store.go

@@ -16,8 +16,9 @@ const (
 )
 
 type MasterNodes struct {
-	nodes  []string
-	leader string
+	nodes          []string
+	leader         string
+	possibleLeader string
 }
 
 func (mn *MasterNodes) String() string {
@@ -34,6 +35,10 @@ func (mn *MasterNodes) Reset() {
 		glog.V(0).Infof("Resetting master nodes: %v", mn)
 	}
 }
+func (mn *MasterNodes) SetPossibleLeader(possibleLeader string) {
+	// TODO try to check this leader first
+	mn.possibleLeader = possibleLeader
+}
 func (mn *MasterNodes) FindMaster() (leader string, err error) {
 	if len(mn.nodes) == 0 {
 		return "", errors.New("No master node found!")