Service task is missing task definition

Hello,
I am new to Camunda and working with the videos from Videos - Camunda.
In the third video when I create a process with three service tasks in the modeler (camunda-modeler-5.0.0-win-x64), I cannot add an implementation to the service tasks because there is no implementation field in the properties panel.

Instead, there is a field asking for a task definition, and the modeller gives me an error message saying:
“A Service Task must have a Task definition type”

I had no problems with the service tasks from the second video, which are created with an Maven archetype. But whenever I create a service task directly in the modeler, the task definition type problem occurs.

Thank you for any help
Susanne

Hey @Susanne

an service task needs a task definition / type.

A camunda platform 8 service task is what you might know from camunda platform 7 as external tasks.

You can also take a look at the following getting started guide

Hope that helps.

Greets
Chris

Hello Chris,

Thank you very much!
The documentation is interesting but does not really answer my question which is:
Some service tasks I created in the modeler do not ask for a task definition type, I assume they got a task definition automatically.
Other service tasks are missing the task definition type! What should I enter in the task definition field of the properties panel? This is not covered in the video tutorials I mentioned.

Best regards
Susanne

Hey @Susanne

this is interesting maybe you can share your process model so we can have a look together :slight_smile:

The task type is like an identifier which you use on the task and your corresponding job worker. The worker with the same type will pick up the corresponding jobs.

More information about job worker Job workers | Camunda Platform 8

Greets
Chris

Dear Chris,

Thank you very much!

Two examples:

  • process.bpmn was created in Eclipse following the instructions from Niall’s second video tutorial. It did not ask for a task definition type.
  • RomanEmpire.bpmn is from the third tutorial and is unfinished, since I got here the problem that the modeler is missing the task definition type. I do not know what to enter in the task definition field in properties panel, since this is not necessary in the video.

Thank you very much for looking at it! I hope you can reproduce it :slight_smile:
Susanne
process.bpmn (5.3 KB)
RomanEmpire.bpmn (6.3 KB)

Hey @Susanne

ok, so the videos are talking about getting started with Camunda Platform 7. Camunda 7 supports some different concepts, like referencing a Java delegate (as you mentioned above). Invoking a Java Class from a BPMN 2.0 Service Task | docs.camunda.org

We have recently released Camunda Platform 8 where some concepts differ. Like we have here no longer the ability to directly reference java classes. Every service task is an external task, which can be picked up by some workers and will be completed as soon as the workers are done with their job.

The modeler you’re using supports the creation of Camunda Platform 7 and 8 models. Depending on which version (for your models) you use different properties will exist during modeling. This is also the reason why you saw in one model only the task type. The recent modeler version comes with a built-in linter mechanism which marks this as an issue if you do not specify a type.

If you want to create a model for Camunda 7 please make sure to choose the right type/version.
Use File > New File > BPMN Diagram (Camunda Platform 7)

Hope that helps.

Greets
Chris

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Yes, now the problem is clear! Thank you very much, Chris!

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