With the group I did draw around the two tasks I want to mark the technical transaction I want to create.
If the Validatation Task fails I want to roll back to the task bevore the data was collected, since the data might be corrupted. Also there may be more tasks in this group than just the two.
Basically what I want to do is, treat the different calls to the external tasks as one and start at the beginning of the Transaction, without Modelling alle the required steps.
This article indicates that this is possible:
I have read some Information about this topic:
and more …
In the forum the following comment indicates that my plan is not possible:
Is it possible to do this in Camunda or do I have to a Bpmn-Transaction and handle the this with an appropriate error boundry event?
The post you reference was about using escalation error boundary events on user tasks, not on subprocesses. In the latest release of Camunda, these options were also added.
You added a group instead of a subprocess. Groups are only used for visual marking and don’t have any execution semantics AFAIK.
With validation tasks, I’d typically opt to follow them by an exclusive gateway, that deals with either success or failure (both normal outcomes of the validation itself). For the validation failed scenario, go to an error end event, catch it on the subprocess boundary and restart the subprocess. This is fully supported.