Solutions Needed: Implementing Previous Tasks and User Operations in Camunda 8 BPMN Processes

[Rabeb_Abid]

Hello,

I’m facing two challenges with Camunda 8:

1. I need assistance implementing a previous task.
2. I also have to perform operations within a user task. Can I utilize a job worker for this, and if so, how should I handle it if there are multiple user tasks in my BPMN process?

Appreciate any help you can provide. Thank you.

[nathan.loding]

Hi @Rabeb_Abid, welcome to the forums! What do you mean “implementing a previous task”?

What operations need to be done in a user task? It is better to explicitly model all the steps, so if there are multiple steps that happen within a single task, it would be recommended to break it out into multiple tasks. You can register a job worker to listen for user tasks, but it will be invoked for every user task that is created in the process. You would need to add logic to your job worker to ignore other tasks if needed. There are several examples of users doing this if you search on the forums.

[Rabeb_Abid]

hi , First and foremost, I would like to express my appreciation for the fantastic support and resources provided.

• problem 1
  I have encountered a challenge in my journey with Camunda, specifically in implementing functionality to move back from Task C to Task B within a simple process consisting of three tasks: Task A → Task B → Task C. What I am trying to achieve is the ability to navigate back to the previous task with associated variables using APIS.

Here is a brief overview of my process:

• Task A
• Task B
• Task C

And my goal is to transition from Task C back to Task B, carrying over specific variables.

• problem 2
  and this is a image to expline what mean about performing operations within a user task . this are a user task , and i want to do simple calcul in each task , for first version . then i need to do a complexe operation . i use spring boot .
  
  

[nathan.loding]

Hi @Rabeb_Abid - for the first problem, you should try to explicitly model the return path. It is strongly recommended that you do not alter running processes via the API. That said, Zeebe supports a ModifyProcessInstance gRPC call that can move to another task. Another user asked a similar question yesterday, so it may be helpful to join the conversation in that topic: previous Task in camunda 8

For the second problem, I would again suggest explicitly modeling those tasks. For instance, before your user task, have a script task that does the calculation you need with FEEL and stores it in a process variable. Or it could be a service task that invokes a job worker you created that does a more complex calculation than can be done with FEEL alone. There are a few different ways to approach it, but you should do the calculations in its own task.

[Rabeb_Abid]

Hello nathan,

I hope this message finds you well. I’m reaching out because I’m currently facing an issue with migrating my application from Camunda 7 to Camunda 8.

Specifically, I’m trying to execute a complex processing when a user task is completed in Camunda 8, a functionality we used to handle with listeners in Camunda 7.

I’m wondering if there’s a recommended approach to achieve this goal in Camunda 8. Are listeners still the best solution, or are there new features or changes in how this should be approached in Camunda 8?

I would be grateful if you could share your knowledge and experiences on this matter. Any suggestions, resources, or examples would be greatly appreciated.

Thank you very much for your invaluable assistance.

Best regards,

[nathan.loding]

Hi @Rabeb_Abid - as mentioned before, explicitly modeling each step of the complex processing is the best place to start. There are no listeners in C8 the way there were in C7, for a variety of reasons, so the approach to solving the problem will be slightly different with C8.