Golang Task.DesiredState方法代碼示例

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)
	}
}

// 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
}