Message Flow to Task within Sub Process (Expanded / Collapsed)



I try to figure out how I have to model a message flow to a task within a sub process. I want to have two different views of the same process:
(a) a detailed view where the sub process is expanded
(b) an overview diagram, where my sub process is collapsed

I came up wit the following solution:

I’m unsure if the collapsed version is semantically right. I fear that there will be two instances of the sub process invoked, which are not correlated. I didn’t find any clues in the spec how to draw a message flow to a collapsed sub process correctly.

Can anyone help me with this? Thanks



Are you modeling BPMN for documentation purposes or for automation with Camunda?


Hi Thorben.

This model here is for documentation purposes. Later on in our project we will have to transfer it to an executable model.




Hi Andreas,

For documentation purposes, I think your models are fine. As far as I know, a message flow connected to a collapsed sub process does not have the semantics of instantiating the subprocess. It merely means that in the context of the sub process, a message is received. At least that is the case for collapsed pools.

As a rule of thumb, try to model it the way you think the people reading the model will understand it. If you believe they will be unsure about the semantics of the second model, then it may be a good idea to improve the model by a) adding documentation elements explaining this b) modeling this in another way or c) leaving the model out.

For automation purposes, it is not really a problem either, since Camunda does not interpret message flows.