How to fix the error: "A <Process> is not allowed to contain a straight-through processing loop"

BPMN & Modeling
1

I am new to Camunda, and this is my first diagram. I would like to represent this simple sub-process that makes sense from the human perspective, but Camunda indicates the following error: “A is not allowed to contain a straight-through processing loop”

sample
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The issue is with the line indicated in red, it seems it is not allowed, but I don’t know how to circumvent it. Thanks for your help on this.

2

There are two issues here.

  1. Task types - because you haven’t given any of the tasks a task type (e.g. User Task, Service task) this process has the potential to spin around infinatly. So this is why you’re getting the A is not allowed to contain a straight-through processing loop error
  2. Deadlock - Even if you did add the task types by adding a sequence flow tot he parallel gateway like that it’ll cause a deadlock. It’s because of how mergin gateways work. I talk about that in this tutorial.
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3

thanks for your fast response. I see the issue is mainly because I am using a generic task. The reason I did that is because when I select a user task for example, I got another error indicating I need to provide a Form. I don’t know where to provide that and on top of that I don’t need a form in this case. This is just to demonstrate the issue in a sample model from my real model. In the video you shared I don’t see were in particular (which minute of the video) you address the case you want to loop back to the beginning of the split parallel gateway to start over again. Please advise how I can avoid the deadlock you mentioned. I need this feedback loop to iterate several times until there is no issue to fix. Thanks in advance. David

4

OK, I was able to fix the deadlock issue, with the following diagram:

image
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when click on Implementation I get the following errors:

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Why is that?

I was able to fix it following the instruction from here: Migrate to Camunda user tasks, but this step is not really necessary, I don’t need a form in my example. Is there a way to fix it without creating a form. In the form type the user can select none but it doesn’t eliminate the error message.

Thanks in advance for your help

5

You don’t need to worry about those. Those are not errors, they’re just warnings. The process will still run.

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