Session recovery after work restart

Community Support
1

Hey, I’m trying to use sessions on my Temporal workers. When I’m redeploying workers the activities get shut down gracefully(not always), however the session is then lost and not completed. Is there a way when the workflow gets started again to recreate the same session and continue the activities?

I’ve created a very basic test setup where I’ve tested multiple approaches but can’t really get it to work.

  1. Start the worker.
  2. Start the workflow.
  3. When activity 1 is being executed send a SIGINT.
  4. Restart the worker.
  5. Activity 2 is cancelled.
func Workflow(ctx workflow.Context, name string) (string, error) {
	ao := workflow.ActivityOptions{
		StartToCloseTimeout: 300 * time.Second,
	}

	var err error
	ctx = workflow.WithActivityOptions(ctx, ao)
	ctx, err = workflow.CreateSession(ctx, &workflow.SessionOptions{
		ExecutionTimeout: 300 * time.Second,
		CreationTimeout:  60 * time.Second,
		HeartbeatTimeout: 10 * time.Second,
	})
	if err != nil {
		return "", err
	}
	defer workflow.CompleteSession(ctx)

	logger := workflow.GetLogger(ctx)
	logger.Info("HelloWorld workflow started", "name", name)

	var r1 string
	var r2 string

	// activity 1
	if err := workflow.ExecuteActivity(ctx, Activity, name).Get(ctx, &r1); err != nil {
		return "", err
	}

	// activity 2
	if err := workflow.ExecuteActivity(ctx, Activity, name).Get(ctx, &r2); err != nil {
		return "", err
	}

	return r1 + r2, nil
}

func Activity(ctx context.Context, name string) (string, error) {
	logger := activity.GetLogger(ctx)
	logger.Info("Activity start", "name", name)

	for i := 0; i <= 5; i++ {
		time.Sleep(time.Second)
		fmt.Println(name, i)
		activity.RecordHeartbeat(ctx)
	}

	logger.Info("Activity end", "name", name)
	return "Hello " + name + "!", nil
}