DevForce Community Forum : Serial Coroutines and ManagedThreadId

Serial Coroutines and ManagedThreadId : Thanks, I was testing this in...

Mon, 01 Nov 2010 20:27:41 -700

Author: stephenmcd1
Subject: 2277
Posted: 01-Nov-2010 at 8:27pm

Thanks, I was testing this in two place. One was a unit test which we expect to fail. The other was in a Silverlight app but I found that it was something else that was messing with my entity manager so mystery solved. Thanks for the help.

Serial Coroutines and ManagedThreadId : It should be possible with serial...

Fri, 29 Oct 2010 15:52:51 -700

Author: kimj
Subject: 2277
Posted: 29-Oct-2010 at 3:52pm

It should be possible with serial execution, and does work in our tests.

I can think of two reasons why you might get this error:

The Uow.EntityManager was constructed on another thread, or
You're running in a test environment (or a console application) which does free threading and doesn't synchronize threads to the context.

Serial Coroutines and ManagedThreadId : I've run into problems when...

Fri, 29 Oct 2010 12:55:32 -700

Author: stephenmcd1
Subject: 2277
Posted: 29-Oct-2010 at 12:55pm

I've run into problems when using Serial Coroutines with respect to the ManagedThreadId property on the EntityManager. The exception specifically says that I should "Consider calling the EntityManager’s asynchronous methods; they work safely on background threads managed by DevForce. " I thought I was using the asynchronous methods so I was expecting it to work. An example of the code is as follows:

        public void TestCoroutine(AsyncEventCompletedCallback> callback)        {
            //Get the entity manager from somewhere
            var myEntityManager = Uow.EntityManager;

            Coroutine.Start(
                () => BuildBasicCoroutine(myEntityManager),
                op =>
                    {
                        //Always fails
                    });
        }

        private static IEnumerable BuildBasicCoroutine(DataModelEntityManager em)
        {
            yield return em.Users.ExecuteAsync();
            yield return em.Contracts.ExecuteAsync();
        }

If I switch it to use Coroutine.StartParallel it will succeed just fine but in many cases I actually need serial behavior becaues one query depends on a previous query.

It seems like this should be possible and maybe I'm just doing something basic wrong. Any help would be appreciated.