ServiceTask property implementation not compatible with Camunda 8 definitions using zeebe header properties

[webravolab]

Hello,

I'm trying to use your beautiful bpmn-engine but found a problem I can't sort out.

In your serviceTask example you use this syntax:

<serviceTask id="serviceTask" implementation="\${environment.services.getRequest}" camunda:resultVariable="serviceResult" />

But I am creating models using bpmn-js graphic library with Camunda 8 properties extensions and the serviceTask is generated as:
<bpmn:serviceTask id="Activity_1vk51oa"> <bpmn:extensionElements> <zeebe:taskHeaders> <zeebe:header key="camunda:resultVariable" value="serviceResult" /> <zeebe:header key="implementation" value="${environment.services.getRequest}" /> <zeebe:header /> </zeebe:taskHeaders> </bpmn:extensionElements> <bpmn:incoming>Flow_0ns1uod</bpmn:incoming> <bpmn:outgoing>Flow_1j3haa6</bpmn:outgoing> </bpmn:serviceTask>

In migration guide https://unsupported.docs.camunda.io/8.3/docs/guides/migrating-from-camunda-7/adjusting-bpmn-models/#service-tasks it says that camunda:resultVariable has been moved to bpmn:extensionElements taskHeader.

How can I change to make the engine recognize the new parameters?
I've also tried to change how the graphic modeler write these properties but also using the Camunda 7 library doesn't work.
Must I customize the modeler to use your notation or can I customize the engine to accept the new notation?
Thank you for your help and keep up the great working you're mading.
Paolo

[paed01]

For Camunda 7 you can use @onify/flow-extensions which has decent feature coverage.

For Camunda 8 there are no extension published on npm, AFAIK. But fear not!

First of all, the engine and elements library are extension agnostic, they only support BPMN2 core elements and attributes. There are possibilities to extend the behaviours. Start looking at Extension docs and test your way into making a Camunda-8-service-task-extension. You can also have a look at, the above mentioned, @onify/flow-extensions for guidance.

You should probably use zeebe-bpmn-moddle as moddle-options.

[webravolab]

Thank you for your prompt reply, I'll look into it and make some tests.