Search Resource In Practice For Beginner

[Dave_Maxwell]

I’m a newcomer to the community, and my team is doing some technical experiments based on Zeebe. I don’t have much experience. But I was assigned some tasks, and I have spent a long time reading the official documentation. However, I always hope to find some actual code or executable examples. For instance, I am currently learning about the part related to Business Rule Task and DMN integration, but I haven’t found corresponding code examples. Is it because of my search query? I noticed there is a code repository(GitHub - camunda/camunda-bpm-examples: A collection of usage examples for Camunda Platform intended to get you started quickly) on GitHub, but it seems not to be for version 8. Moreover, there are significant differences in modeling between version 8 and version 7, and I have been confused for a long time. Below are some documents I found, if possible, please tell me where I should look for more information.
resources:
https://docs.camunda.io/docs/
Camunda 8 Self-Managed | Camunda 8 Docs
GitHub - camunda/camunda-bpm-examples: A collection of usage examples for Camunda Platform intended to get you started quickly
Introduction to Camunda 8 | Camunda 8 Docs

And this is my issue about Business Rule Task.
When I start process, it stopped at Business Rule Task.I passed the variables called “Temperature” and “Activity” when process started.

Any advice is great for me.

[Niall]

Hi @Dave_Maxwell

Camunda 7 and Camunda 8’s most fundamental difference is that Camunda 8 uses a new process engine - Zeebe. The engine is what executes the BPMN, but the DMN engine and modeler are more or less unchanged.

But as you’ve obviously noticed, there are something on how BPMN integrates with DMN. They both use business rule task as the integration point but how the output is death with is a big change. Zeebe uses JSON as it’s native data structure and C7 didn’t. This will actually end up making things a lot easier when returning variables back.

When it comes to documentation on DMN for camunda 8 you can check this out.
And information about how to integrate it with Camunda 8’s business rules task is here.

If there’s a specific things that you’re trying to achieve and you’re having issues feel free to post again and we can try to direct you to the answer

[Dave_Maxwell]

Thank you for your reply, as swift as a rocket.The problem I encountered is actually like this: I created a DMN, and I also deployed it to Zeebe. However, when my process runs, the Business Rule Task does not execute. I have some guesses: first, it might be that my DMN input is incorrect. Second, there might be a problem with my DMN deployment. Third, there might be an issue with my Zeebe. I am investigating, and now that I have provided more information, I hope you can help me analyze.

1. My DMN model designs two input variables just like shown in the picture about DMN. And I put variables called the same name into process as below code:

ProcessInstanceEvent join = zeebeClient.newCreateInstanceCommand().bpmnProcessId("Process_1lkzhwn").latestVersion().variables(Map.of("Temperature", "cold", "Activity", "inside")).send().join();

2. I config the called decision properties in right plane like the picture one, and fill it with DMN Id and result value name in DMN table.

RESULT: But I find that the process is stuck at Business Rule Task.

[Niall]

Can you upload the models you’re using and i’ll try them out.

[cpbpm]

you can use DMN simulator to test your DMN models:
https://consulting.camunda.com/dmn-simulator/

[Dave_Maxwell]

It seems I can only paste two links; I apologize as I’m really not familiar with the community, so I’ve posted them on my GitHub. If it’s not enough, I will provide more information.

GitHub - chenhan-hedgey/zeebe-business-stuck

[Dave_Maxwell]

Oh my friend, it seems my DMN indeed has issues; this website is really fantastic. It appears to have detected that there are undefined inputs in my DMN. Perhaps I should continue to work in this direction.

[Niall]

The model looks good to me, was able to get it working with one change.
The issue seems to be with decisionKey. You entered the name of the DMN file but not the ID. I’ve added screenshots of what i changed.

[Dave_Maxwell]

Oh，I’m so grateful for your reply! Without your hints, I might have spent much more time thinking. I didn’t expect the community’s response to be so fast, and my long-standing issue was resolved so quickly.