use lock defer unlock pattern

saga/inMemorySagaLog.go

@@ -27,41 +27,41 @@ func MakeInMemorySaga() Saga {
 }
 
 func (log *inMemorySagaLog) LogMessage(msg sagaMessage) error {
-	fmt.Println(fmt.Sprintf("Saga %s: %s %s", msg.sagaId, msg.msgType.String(), msg.taskId))
 
+	log.mutex.Lock()
+	defer log.mutex.Unlock()
+
+	fmt.Println(fmt.Sprintf("Saga %s: %s %s", msg.sagaId, msg.msgType.String(), msg.taskId))
 	sagaId := msg.sagaId
-	var err error
 
-	log.mutex.Lock()
 	msgs, ok := log.sagas[sagaId]
 	if !ok {
 		return errors.New(fmt.Sprintf("Saga: %s is not Started yet.", msg.sagaId))
 	}
 
 	log.sagas[sagaId] = append(msgs, msg)
-	log.mutex.Unlock()
-	return err
+	return nil
 }
 
 func (log *inMemorySagaLog) StartSaga(sagaId string, job []byte) error {
 
 	log.mutex.Lock()
+	defer log.mutex.Unlock()
 
 	fmt.Println(fmt.Sprintf("Start Saga %s", sagaId))
 
 	startMsg := MakeStartSagaMessage(sagaId, job)
 	log.sagas[sagaId] = []sagaMessage{startMsg}
 
-	log.mutex.Unlock()
-
 	return nil
 }
 
 func (log *inMemorySagaLog) GetMessages(sagaId string) ([]sagaMessage, error) {
 
 	log.mutex.RLock()
+	defer log.mutex.RUnlock()
+
 	msgs, ok := log.sagas[sagaId]
-	log.mutex.RUnlock()
 
 	if ok {
 		return msgs, nil
@@ -75,13 +75,13 @@ func (log *inMemorySagaLog) GetMessages(sagaId string) ([]sagaMessage, error) {
  */
 func (log *inMemorySagaLog) GetActiveSagas() ([]string, error) {
 	log.mutex.RLock()
+	defer log.mutex.RUnlock()
+
 	keys := make([]string, 0, len(log.sagas))
 
 	for key, _ := range log.sagas {
 		keys = append(keys, key)
 	}
 
-	log.mutex.RUnlock()
-
 	return keys, nil
 }