Generically Pass Parameters to every subprocess

Camunda 7 Topics Discussion & Questions
1

I have a hashmap that tracks request information, that I want to generically pass to every subprocess I invoke in BPMN. Is there any easy way to accomplish this other than modifying the input parameters inside the modeler of every bpmn file?

2

Is the subprocess the same bpmn?

You could have the sub-process execute a delegate/script that accesses the “parent process” and grabs your hashmap variable.

3

It is across separate bpmns, I just want to propagate the larger transaction context for logging without manual work on each new bpmn created.

4

Hi @Ramlaen
you maybe can make use of a process engine plugin.

As an example we created once a process engine plugin that automatically passes the business key to the sub process that is called by a call activity. Per default you would have to check the checkbox on business key on every call activity. You can find the example here: https://github.com/camunda-consulting/code/tree/master/snippets/bpmn-parse-listener-on-call-activity
Maybe this helps you to build your custom plugin or you reuse it to pass the business key and then based on the business key you do a variable query.

Best
Felix

5

Yes this looks very promising, now I just have to figure out how to access and add to the input variables. The documentation is not so straight forward.

6

I had some more time to play with this, while this seems fine in the debugger. It does not appear to get deployed to the bpmn itself. I can see the new attribute added with source/target just like the others are. I am not sure where I am going wrong.

@Override
public void parseCallActivity(Element callActivityElement, ScopeImpl scope, ActivityImpl activity) {	
Element extensionElement = callActivityElement.element("extensionElements");
    	AttributesImpl attributes = new AttributesImpl();
    	attributes.addAttribute("", "", "source", "source", "request-id");
    	attributes.addAttribute("", "", "target", "target", "request-id");
    	Element traceInput = new Element("http://camunda.org/schema/1.0/bpmn", "in", null, attributes, null);
    	extensionElement.add(traceInput);
7

I was able to figure it out I was just adding the variables wrong.

CallableElementActivityBehavior callableElementActivityBehavior = (CallableElementActivityBehavior) activity.getActivityBehavior();
	AttributesImpl attributes = new AttributesImpl();
	attributes.addAttribute("", "", "source", "source", "gOpenTracerContext");
	attributes.addAttribute("", "", "target", "target", "gOpenTracerContext");
	 
	Element traceInput = new Element("http://camunda.org/schema/1.0/bpmn", "in", null, attributes, null);
	CallableElementParameter parameter = parseCallableElementProvider(traceInput);
	callableElementActivityBehavior.getCallableElement().addInput(parameter);
8

Hi @Ramlaen
What is parseCallableElementProvider

9