In my previous previous post on the WCF Fault Spike and the other post on 4 Tenets of Service Oriented Data Validation I discussed some options and best practices for service data validation with WCF.  In this post I want to consider how the same scenario applies to WF4. Download Sample Code – WCF Service Fault and Validation Example I created an application that ran three scenarios each resulting in an exception thrown from the service and a web UI page then shows what the sender can do based...

Remember the 4 tenets of SOA?  One of them is that Boundaries are explicit.  When somebody sends data to your service it is just like when you cross an international border into another country.  Just a couple of hours drive north of us in Redmond is the border crossing to Canada.  When you cross into Canada or back into the United States you have to stop your car and the border agents do their job.  Their job is to make sure that you have proper documentation and that you...

Ready to have some fun… Today I spent the day investigating WCF FaulContracts and FaultException and some best practices for argument validation.  I’m going to do the same in a future post on Workflow Services but I felt it best to really understand the topic from a WCF point of view first. Investigation Questions What happens when a service throws an exception? What happens if a service throws a FaultException? What happens if the service operation includes a FaultContract and it throws a FaultException<TDetail>...

This morning I’ve been working on how to support cancelling a workflow via a CancellationToken.  The details of that are not important right now but what is really cool is how I was able to test this. Scenario: Caller requests Cancellation via a CancellationToken and the UnhandledExceptionAction is Cancel Given An activity that contains a CancellationScope The CancellationScope body has an activity that will create a bookmark and go idle The CancellationScope has a CancelHandler with a WriteLine...

With the work I’ve been doing on versioning I’ve had to write unit tests that verify the behavior I expect from the helper classes in Microsoft.Activities.dll .  If you want to verify that your assembly versioning strategy is working correctly you may have to do similar testing.  This sort of testing is tricky… in this post I’ll share with you my solutions to some tough problems. Test Problem: Multiple Versions of the Same Assembly in a Test Run There is only one deployment directory for...