Metastorm BPM 7.6 and Windows Workflow part 6 - state machines

This will almost certainly be my last post about executing Windows Workflows from Metastorm BPM as I think I've covered pretty much everything there is to cover (although leave a comment if there is something I've missed).

One of the comments from one of the previous posts was regarding state machine workflows and whether these could be executed from the Metastorm environment. So I knocked together a simple state machine workflow in Visual Studio that starts, waits in its initial state for 5 minutes then moves to the final state.

As discussed before, there is no support for publishing your own VS authored workflows to the Metastorm database so I modified the little command-line tool I wrote previously to cope with state machine workflows. For brevity I won't post all the source, just the change required, which is as follows.

        for (int i=0; i<types.Length; i++)
        {
          if (types[i].IsSubclassOf(typeof(SequentialWorkflowActivity)))
          {
            workflowType = types[i];
            break;
          }
          else if (types[i].IsSubclassOf(typeof(StateMachineWorkflowActivity)))
          {
            workflowType = types[i];
            break;
          }
        }

So after publishing the workflow, I tried to execute it from Metastorm and it worked as expected. Cool.

The next test was to see what happened when I restarted the engine whilst a workflow was executing, since this caused problems with sequential workflows. I was expecting the same problem, since state machine workflows execute in the same way as sequential workflows. And I was correct in my supposition, the workflow never completed.

So in conclusion, state machines can be used in Metastorm but you'll need to hack the database. But WF in Metastorm won't be of use to you if you need to execute long running workflows. Which is a shame since this is probably the main purpose of WF.

Part 1 - The basics

Part 2 - The database tables

Part 3 - Using Visual Studio

Part 4 - Using your own activities

Part 5 - Long running workflows