topic Re: Return to calling process but continue asyncronously in Alfresco Archive

Return to calling process but continue asyncronously

mlueck — Wed, 19 Oct 2016 09:21:49 GMT

Hi,we have the following setting: A Parent process which calls another process (the child) via call activiti and defined out parameters for this call because we need an result from the child in the parent After the child has created the needed result we want to pass this to the parent and continue

Re: Return to calling process but continue asyncronously

mlueck — Thu, 20 Oct 2016 06:45:08 GMT

Ok after more searches in the forums i found this thread.

Basically it's stating that a CallActiviti must always wait for the called process instance to finish.

As far as i understood subprocesses and CallActivity's are not very different in the way there are executed. Actually The CallActivityBehavoiur is implementation of the SubprocessBehavior. The CallActivity will not leave until the called is finished.

I assume that the called process is not finished until all end states are reached.

Re: Return to calling process but continue asyncronously

warper — Thu, 20 Oct 2016 09:44:48 GMT

You can set parent process variables from child process. It looks like execution.getParent().setVariable("a","a-value")
You can send signals/messages to parent process. To avoid transaction context nesting you may need async signals, but it's up to you.
So, you can make parallel gateway in parent process, top line waits on signal, bottom line does call activity. Child process sets variables of parent process, then sends signal and continues its work as needed.

Re: Return to calling process but continue asyncronously

mlueck — Thu, 20 Oct 2016 11:57:55 GMT

Hi,

thanks for the answer. I already had a look at events and stuff and now connected parent and child through a message event.
The parent call activiti get's an non interupting message boundary catch event which leads to an service task which will sent a message to an external system. The child process has a script task which will sent a message event to the parent and then proceed which the remainder of the process.

The CallActiviti will still wait for the subprocess to complete but that's ok. So it would also be possible to to more things in the parent if necessary.

If you're interested or if anybody has the same issue i uploaded a test project to github which contains the processes and a junit test to show the usage.