Fail fast mechanism when to send a task to non-exist workflow/activity queue

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1

Hello!

I’m curious does temporal have a fail fast mechanism to prevent sending tasks to non-exist queue?

The reason to ask the question is when queue is incorrectly specified (due to refactoring for example) in Workflow/Activity options there is no exception or warning/error.

Let’s consider an example which relates to java sdk + spring boot (it’s a modified example from samples):

@WorkflowImpl(taskQueues = "HelloSampleTaskQueue")
public class HelloWorkflowImpl implements HelloWorkflow {
...
...
...
}


ResponseEntity<String> helloSample(@RequestBody Person person) {
    HelloWorkflow workflow = client.newWorkflowStub(HelloWorkflow.class,
            WorkflowOptions.newBuilder()
                .setTaskQueue("HelloSampleQueue") <------------------ queue name doesn't match
                .setWorkflowId("HelloSample")
                .build());
...
...
...
}

In that case workflow is just running

2

For activities you can rely on ActivityOptions->ScheduleToStart timeout, for example:

      private final MyActivities activities =
              Workflow.newActivityStub(
                  MyActivities.class,
                  ActivityOptions.newBuilder().setStartToCloseTimeout(Duration.ofSeconds(5))
                          .setScheduleToStartTimeout(Duration.ofSeconds(3))
                          .setTaskQueue("invalid_name")
                          .build());
     // ...

      try {
        activities.doSomething(input);
      } catch (ActivityFailure af) {
        if(af.getCause() instanceof TimeoutFailure) {
          TimeoutFailure tf = (TimeoutFailure) af.getCause();
          if(tf.getTimeoutType() == TimeoutType.TIMEOUT_TYPE_SCHEDULE_TO_START) {
            // route activity (schedule it again) on correct task queue if needed  
            // ...
          }
        }
3

@tihomir thank you very much for the quick answer!

ScheduleToStart could be a solution for my case.

But am I right that Temporal does not support any validation mechanisms for task queues because queues declaration happens only on worker registration step?

4

Correct, task queues configured in worker options are dynamically created if not already exist when worker starts polling.

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