Ejemplo n.º 1
0
// Start worker runs the worker command
func (manager *workerManager) Start(queues []string) {
	sigs := make(chan os.Signal, 1)
	done := make(chan bool, 1)

	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
	go func() {
		<-sigs // listen to signals
		manager.Stop()
		manager.Close()
		log.Info("gocelery stopped.")
		done <- true // send signals to done
	}()

	log.Debug("Worker is now running")

	// now loops to wait for messages
	manager.sendWorkerEvent(WorkerOnline)

	// start hearbeat
	manager.startHeartbeat()

	// start getting tasks
	taskChannels := make([]<-chan *broker.Message, 3)
	for _, queue := range queues {
		taskChannel := manager.broker.GetTasks(queue)
		taskChannels = append(taskChannels, taskChannel)
	}
	ch := merge(done, taskChannels...)
	for {
		select {
		case <-done:
			log.Debug("Received done signal")
			return
		case message := <-ch:
			log.Debug("Message type: ", message.ContentType, " body:", string(message.Body))
			go func(message *broker.Message) {
				serializer, err := serializer.NewSerializer(message.ContentType)
				// convert message body to task
				if err == nil {
					var task Task

					err = serializer.Deserialize(message.Body, &task)
					if err == nil {
						task.ContentType = message.ContentType // stores the content type for the task
						// publish task received event
						taskEventPayload, _ := serializer.Serialize(NewTaskReceivedEvent(&task))
						manager.broker.PublishTaskEvent(strings.Replace(TaskReceived.RoutingKey(), "-", ".", -1),
							&broker.Message{
								Timestamp:   time.Now(),
								ContentType: message.ContentType,
								Body:        taskEventPayload,
							})
						log.Debug("Processing task: ", task.Task, " ID:", task.ID)

						// check eta
						duration := time.Duration(0)
						if !task.Eta.IsZero() {
							duration = task.Eta.Sub(time.Now().UTC())
						}
						if duration > 0 {
							timer := time.NewTimer(duration) // wait until ready
							go func() {
								<-timer.C
								manager.runTask(&task)
							}()
						} else {
							// execute the task in a worker immediately
							manager.runTask(&task)
						}
					}
				} else {
					// send errors to server
					log.Error("Cannot deserialize message:", err)
				}
			}(message)
		}
	}
}
Ejemplo n.º 2
0
func (manager *workerManager) runTask(task *Task) (*TaskResult, error) {

	// create task result
	taskResult := &TaskResult{
		ID:     task.ID,
		Status: Started,
	}

	taskEventType := None
	serializer, _ := serializer.NewSerializer(task.ContentType)
	var taskError error
	var taskEventPayload []byte

	if worker, ok := workerRegistery[task.Task]; ok {
		log.Debug("Working on task: ", task.Task)

		taskEventPayload, _ = serializer.Serialize(NewTaskStartedEvent(task))
		taskEventType = TaskStarted
		manager.sendTaskEvent(TaskStarted, taskEventPayload)

		// check expiration
		if !task.Expires.IsZero() && task.Expires.Before(time.Now().UTC()) {
			// time expired, make the task Revoked
			log.Warn("Task has expired", task.Expires)
			taskResult.Status = Revoked
			taskError = errors.New("Task has expired")
			taskEventPayload, _ = serializer.Serialize(NewTaskFailedEvent(task, taskResult, taskError))
			taskEventType = TaskRevoked
		} else {
			start := time.Now()
			result, err := worker.Execute(task)
			elapsed := time.Since(start)

			manager.Lock()
			manager.taskExecuted = manager.taskExecuted + 1
			log.Infof("Executed task [%s] [%s] [%s] in %f seconds", task.Task, task.ID, result, elapsed.Seconds())
			manager.Unlock()

			if err != nil {
				log.Errorf("Failed to execute task [%s]: %s", task.Task, err)
				err = errors.Wrap(err, 1)
			}

			if err != nil {
				taskError = err
				taskResult.Status = Failure
				taskResult.TraceBack = err.(*errors.Error).ErrorStack()
				taskEventPayload, _ = serializer.Serialize(NewTaskFailedEvent(task, taskResult, err))
				taskEventType = TaskFailed
			} else {
				taskResult.Status = Success
				taskResult.Result = result
				taskEventPayload, _ = serializer.Serialize(NewTaskSucceedEvent(task, taskResult, elapsed))
				taskEventType = TaskSucceeded
			}
		}
	} else {
		taskErrorMessage := fmt.Sprintf("Worker for task [%s] not found", task.Task)
		taskError = errors.New(taskErrorMessage)
		taskResult.Status = Failure
		taskResult.TraceBack = taskError.(*errors.Error).ErrorStack()
		taskEventPayload, _ = serializer.Serialize(NewTaskFailedEvent(task, taskResult, taskError))
		taskEventType = TaskFailed
	}

	res, _ := serializer.Serialize(taskResult)
	//key := strings.Replace(task.ID, "-", "", -1)
	manager.broker.PublishTaskResult(task.ID, &broker.Message{Timestamp: time.Now(), ContentType: task.ContentType, Body: res})

	// send task completed event
	if taskEventType != None {
		manager.sendTaskEvent(taskEventType, taskEventPayload)
	}

	return taskResult, nil
}