StateMachines : Implementation of WF in AS3

I have now successfully ported a minimal subset of the Windows Workflow Foundation to AS3. Initially I have created Sequential and StateMachine Workflows with just a set of non-nestable Activities.

Next point of focus is on implementing a set of sample applications which will illustrate the power of having an event-driven application based on StateMachines as well as a number of Applications illustrating how easy keeping a complex set of activities in strictly sequence using the SequentialWorkflow.

Another important aspect right now is to get the WorkflowRuntime just right as it right now pretty much only works as a Workflow factory.

State Machines : Windows Workflow Foundation

Windows Workflow Foundation has buildin support for building state-machine workflows to be used from any dotNet based host.

I will explore this in the upcoming weeks in relation to my effort to contribute to the further development of State Machine support in the PureMVC framework.

Check it out...
http://msdn.microsoft.com/en-us/netframework/aa663328.aspx

State Machines : Basic Thoughts

There is one important decision to make when creating a new workflow. Will the workflow be a sequential workflow, or a state machine workflow? Windows Workflow provides these two types out of the box. To answer the question, we have to decide whois in control.

A sequential workflow is a predictable workflow. The execution path might branch, or loop, or wait for an outside event to occur, but in the end, the sequential workflow will use the activities, conditions, and rules we've provided to march inevitably forward. The workflow is in control of the process.

A state-machine workflow is an event driven workflow. That is, the state machine workflow relies on external events to drive the workflow to completion. We define the legal states of the workflow, and the legal transitions between those states. The workflow is always in one of the states, and has to wait for an event to arrive before transitioning to a new state. Generally, the important decisions happen outside of the workflow. The state machine defines a structure to follow, but control belongs to the outside world.

We use a sequential workflow when we can encode most of the decision-making inside the workflow itself. We use a state machine workflow when the decision-making happens outside the workflow.