rename EtcdStore to Etcd

go/cmd/master/master.go

@@ -32,7 +32,7 @@ func main() {
 	if *endpoints != "" {
 		eps := strings.Split(*endpoints, ",")
 		var err error
-		store, err = master.NewEtcdStore(eps, master.DefaultLockPath, master.DefaultStatePath, *ttlSec)
+		store, err = master.NewEtcd(eps, master.DefaultLockPath, master.DefaultStatePath, *ttlSec)
 		if err != nil {
 			log.Fatal(err)
 		}

go/master/etcd_store.go

@@ -16,8 +16,9 @@ const (
 	DefaultStatePath = "/master/state"
 )
 
-// EtcdStore is the Store implementation backed by etcd.
-type EtcdStore struct {
+// Etcd is the etcd abstraction that master uses for fault tolerance
+// and service registry.
+type Etcd struct {
 	lockPath  string
 	statePath string
 	ttlSec    int
@@ -27,8 +28,8 @@ type EtcdStore struct {
 	lock *concurrency.Mutex
 }
 
-// NewEtcdStore creates a new EtcdStore.
-func NewEtcdStore(endpoints []string, lockPath, statePath string, ttlSec int) (*EtcdStore, error) {
+// NewEtcd creates a new Etcd.
+func NewEtcd(endpoints []string, lockPath, statePath string, ttlSec int) (*Etcd, error) {
 	// TODO(helin): gracefully shutdown etcd store. Becuase etcd
 	// store holds a etcd lock, even though the lock will expire
 	// when the lease timeout, we need to implement graceful
@@ -59,7 +60,7 @@ func NewEtcdStore(endpoints []string, lockPath, statePath string, ttlSec int) (*
 	}
 	log.Infof("Successfully acquired lock at %s.", lockPath)
 
-	e := &EtcdStore{}
+	e := &Etcd{}
 	e.client = cli
 	e.lock = lock
 	e.lockPath = lockPath
@@ -69,7 +70,7 @@ func NewEtcdStore(endpoints []string, lockPath, statePath string, ttlSec int) (*
 }
 
 // Save saves the state into the etcd.
-func (e *EtcdStore) Save(state []byte) error {
+func (e *Etcd) Save(state []byte) error {
 	e.mu.Lock()
 	defer e.mu.Unlock()
 
@@ -101,7 +102,7 @@ func (e *EtcdStore) Save(state []byte) error {
 }
 
 // Load loads the state from etcd.
-func (e *EtcdStore) Load() ([]byte, error) {
+func (e *Etcd) Load() ([]byte, error) {
 	e.mu.Lock()
 	ctx := context.TODO()
 	get := clientv3.OpGet(e.statePath)
@@ -119,8 +120,12 @@ func (e *EtcdStore) Load() ([]byte, error) {
 		}
 
 		e.lock = concurrency.NewMutex(sess, e.lockPath)
-		e.lock.Lock(context.TODO())
+		err = e.lock.Lock(context.TODO())
 		e.mu.Unlock()
+		if err != nil {
+			return nil, err
+		}
+
 		return e.Load()
 	}