Golang api.Task類代碼示例

// tasksEqual returns true if the tasks are functionaly equal, ignoring status,
// version and other superfluous fields.
//
// This used to decide whether or not to propagate a task update to a controller.
func tasksEqual(a, b *api.Task) bool {
	a, b = a.Copy(), b.Copy()

	a.Status, b.Status = api.TaskStatus{}, api.TaskStatus{}
	a.Meta, b.Meta = api.Meta{}, api.Meta{}

	return reflect.DeepEqual(a, b)
}

func (w *worker) startTask(ctx context.Context, tx *bolt.Tx, task *api.Task) error {
	w.taskevents.Publish(task.Copy())
	_, err := w.taskManager(ctx, tx, task) // side-effect taskManager creation.

	if err != nil {
		log.G(ctx).WithError(err).Error("failed to start taskManager")
	}

	// TODO(stevvooe): Add start method for taskmanager
	return nil
}

func newTaskManager(ctx context.Context, task *api.Task, ctlr exec.Controller, reporter StatusReporter) *taskManager {
	t := &taskManager{
		task:     task.Copy(),
		ctlr:     ctlr,
		reporter: reporter,
		updateq:  make(chan *api.Task),
		shutdown: make(chan struct{}),
		closed:   make(chan struct{}),
	}
	go t.run(ctx)
	return t
}

// PutTask places the task into the database.
func PutTask(tx *bolt.Tx, task *api.Task) error {
	return withCreateTaskBucketIfNotExists(tx, task.ID, func(bkt *bolt.Bucket) error {
		task = task.Copy()
		task.Status = api.TaskStatus{} // blank out the status.

		p, err := proto.Marshal(task)
		if err != nil {
			return err
		}
		return bkt.Put(bucketKeyData, p)
	})
}

// tick attempts to schedule the queue.
func (s *Scheduler) tick(ctx context.Context) {
	tasksByCommonSpec := make(map[string]map[string]*api.Task)
	schedulingDecisions := make(map[string]schedulingDecision, s.unassignedTasks.Len())

	var next *list.Element
	for e := s.unassignedTasks.Front(); e != nil; e = next {
		next = e.Next()
		t := s.allTasks[e.Value.(*api.Task).ID]
		if t == nil || t.NodeID != "" {
			// task deleted or already assigned
			s.unassignedTasks.Remove(e)
			continue
		}

		// Group common tasks with common specs by marshalling the spec
		// into taskKey and using it as a map key.
		// TODO(aaronl): Once specs are versioned, this will allow a
		// much more efficient fast path.
		fieldsToMarshal := api.Task{
			ServiceID: t.ServiceID,
			Spec:      t.Spec,
		}
		marshalled, err := fieldsToMarshal.Marshal()
		if err != nil {
			panic(err)
		}
		taskGroupKey := string(marshalled)

		if tasksByCommonSpec[taskGroupKey] == nil {
			tasksByCommonSpec[taskGroupKey] = make(map[string]*api.Task)
		}
		tasksByCommonSpec[taskGroupKey][t.ID] = t
		s.unassignedTasks.Remove(e)
	}

	for _, taskGroup := range tasksByCommonSpec {
		s.scheduleTaskGroup(ctx, taskGroup, schedulingDecisions)
	}

	_, failed := s.applySchedulingDecisions(ctx, schedulingDecisions)
	for _, decision := range failed {
		s.allTasks[decision.old.ID] = decision.old

		nodeInfo, err := s.nodeSet.nodeInfo(decision.new.NodeID)
		if err == nil && nodeInfo.removeTask(decision.new) {
			s.nodeSet.updateNode(nodeInfo)
		}

		// enqueue task for next scheduling attempt
		s.enqueue(decision.old)
	}
}

func taskUpdateNetworks(t *api.Task, networks []*api.NetworkAttachment) {
	networksCopy := make([]*api.NetworkAttachment, 0, len(networks))
	for _, n := range networks {
		networksCopy = append(networksCopy, n.Copy())
	}

	t.Networks = networksCopy
}

func newTask(cluster *api.Cluster, service *api.Service, slot uint64, nodeID string) *api.Task {
	var logDriver *api.Driver
	if service.Spec.Task.LogDriver != nil {
		// use the log driver specific to the task, if we have it.
		logDriver = service.Spec.Task.LogDriver
	} else if cluster != nil {
		// pick up the cluster default, if available.
		logDriver = cluster.Spec.TaskDefaults.LogDriver // nil is okay here.
	}

	taskID := identity.NewID()
	task := api.Task{
		ID:                 taskID,
		ServiceAnnotations: service.Spec.Annotations,
		Spec:               service.Spec.Task,
		ServiceID:          service.ID,
		Slot:               slot,
		Status: api.TaskStatus{
			State:     api.TaskStateNew,
			Timestamp: ptypes.MustTimestampProto(time.Now()),
			Message:   "created",
		},
		Endpoint: &api.Endpoint{
			Spec: service.Spec.Endpoint.Copy(),
		},
		DesiredState: api.TaskStateRunning,
		LogDriver:    logDriver,
	}

	// In global mode we also set the NodeID
	if nodeID != "" {
		task.NodeID = nodeID
	}

	// Assign name based on task name schema
	name := store.TaskName(&task)
	task.Annotations = api.Annotations{Name: name}

	return &task
}

func (g *GlobalOrchestrator) removeTask(ctx context.Context, batch *store.Batch, t *api.Task) {
	// set existing task DesiredState to TaskStateShutdown
	// TODO(aaronl): optimistic update?
	err := batch.Update(func(tx store.Tx) error {
		t = store.GetTask(tx, t.ID)
		if t != nil {
			t.DesiredState = api.TaskStateShutdown
			return store.UpdateTask(tx, t)
		}
		return nil
	})
	if err != nil {
		log.G(ctx).WithError(err).Errorf("global orchestrator: removeTask failed to remove %s", t.ID)
	}
}

func taskUpdateEndpoint(t *api.Task, endpoint *api.Endpoint) {
	t.Endpoint = endpoint.Copy()
}

// Restart initiates a new task to replace t if appropriate under the service's
// restart policy.
func (r *Supervisor) Restart(ctx context.Context, tx store.Tx, cluster *api.Cluster, service *api.Service, t api.Task) error {
	// TODO(aluzzardi): This function should not depend on `service`.

	// Is the old task still in the process of restarting? If so, wait for
	// its restart delay to elapse, to avoid tight restart loops (for
	// example, when the image doesn't exist).
	r.mu.Lock()
	oldDelay, ok := r.delays[t.ID]
	if ok {
		if !oldDelay.waiter {
			oldDelay.waiter = true
			go r.waitRestart(ctx, oldDelay, cluster, t.ID)
		}
		r.mu.Unlock()
		return nil
	}
	r.mu.Unlock()

	// Sanity check: was the task shut down already by a separate call to
	// Restart? If so, we must avoid restarting it, because this will create
	// an extra task. This should never happen unless there is a bug.
	if t.DesiredState > api.TaskStateRunning {
		return errors.New("Restart called on task that was already shut down")
	}

	t.DesiredState = api.TaskStateShutdown
	err := store.UpdateTask(tx, &t)
	if err != nil {
		log.G(ctx).WithError(err).Errorf("failed to set task desired state to dead")
		return err
	}

	if !r.shouldRestart(ctx, &t, service) {
		return nil
	}

	var restartTask *api.Task

	if orchestrator.IsReplicatedService(service) {
		restartTask = orchestrator.NewTask(cluster, service, t.Slot, "")
	} else if orchestrator.IsGlobalService(service) {
		restartTask = orchestrator.NewTask(cluster, service, 0, t.NodeID)
	} else {
		log.G(ctx).Error("service not supported by restart supervisor")
		return nil
	}

	n := store.GetNode(tx, t.NodeID)

	restartTask.DesiredState = api.TaskStateReady

	var restartDelay time.Duration
	// Restart delay is not applied to drained nodes
	if n == nil || n.Spec.Availability != api.NodeAvailabilityDrain {
		if t.Spec.Restart != nil && t.Spec.Restart.Delay != nil {
			var err error
			restartDelay, err = ptypes.Duration(t.Spec.Restart.Delay)
			if err != nil {
				log.G(ctx).WithError(err).Error("invalid restart delay; using default")
				restartDelay = orchestrator.DefaultRestartDelay
			}
		} else {
			restartDelay = orchestrator.DefaultRestartDelay
		}
	}

	waitStop := true

	// Normally we wait for the old task to stop running, but we skip this
	// if the old task is already dead or the node it's assigned to is down.
	if (n != nil && n.Status.State == api.NodeStatus_DOWN) || t.Status.State > api.TaskStateRunning {
		waitStop = false
	}

	if err := store.CreateTask(tx, restartTask); err != nil {
		log.G(ctx).WithError(err).WithField("task.id", restartTask.ID).Error("task create failed")
		return err
	}

	r.recordRestartHistory(restartTask)

	r.DelayStart(ctx, tx, &t, restartTask.ID, restartDelay, waitStop)
	return nil
}

// Restart initiates a new task to replace t if appropriate under the service's
// restart policy.
func (r *RestartSupervisor) Restart(ctx context.Context, tx store.Tx, service *api.Service, t api.Task) error {
	// TODO(aluzzardi): This function should not depend on `service`.

	t.DesiredState = api.TaskStateShutdown
	err := store.UpdateTask(tx, &t)
	if err != nil {
		log.G(ctx).WithError(err).Errorf("failed to set task desired state to dead")
		return err
	}

	if !r.shouldRestart(ctx, &t, service) {
		return nil
	}

	var restartTask *api.Task

	if isReplicatedService(service) {
		restartTask = newTask(service, t.Slot)
	} else if isGlobalService(service) {
		restartTask = newTask(service, 0)
		restartTask.NodeID = t.NodeID
	} else {
		log.G(ctx).Error("service not supported by restart supervisor")
		return nil
	}

	n := store.GetNode(tx, t.NodeID)

	restartTask.DesiredState = api.TaskStateAccepted

	var restartDelay time.Duration
	// Restart delay does not applied to drained nodes
	if n == nil || n.Spec.Availability != api.NodeAvailabilityDrain {
		if t.Spec.Restart != nil && t.Spec.Restart.Delay != nil {
			var err error
			restartDelay, err = ptypes.Duration(t.Spec.Restart.Delay)
			if err != nil {
				log.G(ctx).WithError(err).Error("invalid restart delay; using default")
				restartDelay = defaultRestartDelay
			}
		} else {
			restartDelay = defaultRestartDelay
		}
	}

	waitStop := true

	// Normally we wait for the old task to stop running, but we skip this
	// if the old task is already dead or the node it's assigned to is down.
	if (n != nil && n.Status.State == api.NodeStatus_DOWN) || t.Status.State > api.TaskStateRunning {
		waitStop = false
	}

	if err := store.CreateTask(tx, restartTask); err != nil {
		log.G(ctx).WithError(err).WithField("task.id", restartTask.ID).Error("task create failed")
		return err
	}

	r.recordRestartHistory(restartTask)

	r.DelayStart(ctx, tx, &t, restartTask.ID, restartDelay, waitStop)
	return nil
}