Support form group for undefined start event

[marcellobarile]

Is your feature request related to a problem? Please describe.

While working on https://github.com/camunda/web-modeler/issues/4583, to enable the form linking for a start event, we had to copy/paste code from the core libraries in order to have the form group rendered also for such an element.

Describe the solution you'd like

The properties panel should have the form group also for the undefined start event; note that so far this feature is only supported by the web-modeler.

Additional context

Current implementation in the web-modeler:

Duplicated code on the web-modeler:
https://github.com/camunda/web-modeler/blob/56fa51c7ec6a65f7942af360de286ab83bd774bb/webapp/src/App/Pages/Diagram/Publication/publicationPropertiesGroupExtension/FormGroup/FormProperties.js

[smbea]

We should expose the group API in order to avoid the copy/paste

[CatalinaMoisuc]

Let's spend ~1h to understand the effort we need to ship proper groups API and post an assessment in the issue and then decide on priority and capacity.

[barmac]

I transferred this issue from bpmn-io/properties-panel as Form group is implemented in bpmn-js-properties-panel.

If I understand it correctly, you request that we add the form group for bpmn:StartEvent in the Zeebe Properties Provider. So it's not about exposing any groups (via export), but rather supporting a missing feature in bpmn-js-properties-panel.

Apart from adding the group in the properties panel, we'd need to adjust zeebe-bpmn-moddle to make sure the form related properties are kept when a Start Event is copied (https://github.com/camunda/zeebe-bpmn-moddle/blob/main/resources/zeebe.json#L282). Also, we'd need to make sure the properties are removed when None Start Event is transformed into a specified event, e.g. Timer Start Event.

@marcellobarile please let me know if I understood the issue correctly.

[barmac]

To clarify further, if I deploy from Desktop Modeler or another client but not Web Modeler, this feature doesn't work, does it?

[CatalinaMoisuc]

We reviewed this with the last planning and decided to move this back to backlog because it is not a trivial fix and for the time being this feature is still experimental and only available in SaaS and not Self-Managed. When we pick it up for implementation also into Self-Managed, we can bring it back to Ready.