Lightweight async via Groovy & REST?

[roblong]

First, kudos to the entire team, Activiti's been a treat to learn (even for a Java newbie).

Issue: I've had surprising success with fairly complex Activiti workflows, but have failed to integrate Activiti into our async python/php infrastructure.

Use case - Amazon Mechanical Turk process:
- intiate process via human task/form
- enqueue task/process vars via script task
    —  (groovy: add process Vars to Redis queue via jedis)
    —  problem: ProcessInstanceID or BusinessKey not available within <script>
- do external work (Amazon Turk via our existing systems)
    —  may be a multi-day process depending on scope
- integrate back into workflow via REST
    —  problem: assuming I have ProcessInstanceID/BusinessKey  REST api returns png diagram, but not json of current task(s)  (service/process/<123>/diagram)
- wait for human approval
- complete process

Pulling hair out a bit trying to work around these two issues:

  o How to enqueue correlation keys & process variables via groovy/jython script?

  o Determine current task(s) for given correlation key via REST?

I assume I'm missing something obvious… or more likely I'm an edge case, relying on experimental interfaces and just need to bust out the Java Beans/Spring for dummies?

Appreciate any pointers.

- Rob

[frederikherema1]

You can just use varaibles in you script. So if you have a process-variable with name "myProcessvar", it will be available in the script-context as myProcessVar. The business-key is curently not exposed in scripts. A workaround (delegateExecution.getBusinessKey() will be available in activiti 5.6) could be storing the businessKey as variable:

- Use a execution/task listener right before the script-task, using an expression, eg:

<extensionElements>
      <activiti:executionListener expression="${execution.setVariable('theKey', execution.getBusinessKey()}" event="take" />
    </extensionElements>
- In scriptTask, business-key is available under variable theKey

About the REST-API. Not all java-api calls are available through rest. So getting al tasks for a processInstanceID is not possible… You'll have to extend the activiti-rest or write your own servlet/rest-endpoint in the java-app that calls the Activiti java-API I'm affraid…