Interaction between two Camundas

Hello, world.

I have two cases that puzzle me:

  1. How can I start process in another Camunda from service task of another Camunda?

  2. After starting process in 1, I have to wait this external process ending in next task.

Main idea: the process is going on on Camunda A. The first task starts the process on Camunda B and moves on to the next task. Second task just stands and waits until it receives a message from the B (message that the whole running process on B has ended). After that, the task on Camunda A ends and the next tasks begin on A.

I’m just trying to implement some kind of orchestration of orchestrators)

How can I implement such behavior? Okay, probably for the first point, I can just use REST API (I.e A just http-client for B in this case). But second point is hard for me to understand. Please, give me advice.

PS: how properly work with exceptions on B at the A-side? Any ideas.

Thank you in advance!

So i’m assuming that you’re talking about two different camunda distro’s each with their own database.
In this case, it’s pretty easy, you can use message events to trigger processes and wait for responses once they’re done. This is explained as part of this tutorial and on this docs page. You can also check out the best practices documentation for more ideas.