Re: Castle.Windsor: Changes for factory method registration and interceptors in 3.1?

[Nik Pinski]

I think I figured this out

The fact that the interceptor wasn't being assigned to Test in 2.5.3 is a bug/feature disguised as a bug.  The 3.1.0 behaviour is more correct, and forces you to be explicit about what you want an interceptor on.  Since my actual code involved a Facility, here is the solution that fixes the issue:

public class Facility : AbstractFacility

{

    protected override void Init() { Kernel.ComponentRegistered += KernelComponentRegistered; }

    static void KernelComponentRegistered(string key, IHandler handler)

    {

        if (typeof(IInterceptor).IsAssignableFrom(handler.ComponentModel.Implementation)) return; //This is so that interceptors don't intercept themselves

        

        if (handler.ComponentModel.Services.FirstOrDefault() == typeof(Test)) return; //This is so that the interceptor does not intercept our Factory-initialized class

        

        handler.ComponentModel.Interceptors.AddIfNotInCollection(InterceptorReference.ForKey("SomeInterceptor"));

    }

}

On Friday, 28 September 2012 01:34:11 UTC-7, Nik Pinski wrote:

The following code passes as-is with Castle.Windsor 2.5.3 but fails after upgrading to 3.1.0

The exception is an InvalidProxyConstructorArgumentsException and it states "Can not instantiate proxy of class: Test. Could not find a parameterless constructor."

        static void Main(string[] args)

        {

            var container = new WindsorContainer();

            container.Register(Component.For<Interceptor>(),

                               Component.For<Test>().UsingFactoryMethod(() => new Test(""))

                                                    .Interceptors<Interceptor>());

            var test = container.Resolve<Test>(); //THROWS IN 3.1.0

        }

    }

    public class Test

    {

        public readonly string S;

        public Test(string s)

        {

            S = s;

        }

    }

    public class Interceptor : IInterceptor

    {

        public void Intercept(IInvocation invocation)

        {

            invocation.Proceed();

        }

    }

In my real code Test is a MongoDatabase that is being constructed using a factory method and injected into a Repository.  

In my real code I'm also using an inheritor to an AbstractFacility to register the interceptor. This way I don't have to register the interceptor for each component. Both forms of interceptor usage seem to work/fail (in 2.5.3/3.1.0) the same way on later resolution.  For reference here is a shortened version of the facility:

    public class Facility : AbstractFacility

    {

        protected override void Init() { Kernel.ComponentRegistered += KernelComponentRegistered; }

        static void KernelComponentRegistered(string key, IHandler handler)

        {

            if (typeof(IInterceptor).IsAssignableFrom(handler.ComponentModel.Implementation)) return;

            handler.ComponentModel.Interceptors.AddIfNotInCollection(InterceptorReference.ForKey("SomeInterceptor"));

        }

    }

I looked at the Castle.Windsor source code and the throwing code is expecting to wrap a proxy around the class it is given which is why it's looking for a parameterless constructor.  However in 2.5.3 I think the proxy generation code never got executed and the container resolves (correctly in my mind) to a non-proxy version of Test/MongoDatabase

So two questions I guess:

1) What's changed?

2) How do I keep my interceptor registration without generating a proxy for the object resolved by the factory method?  Or I guess how does a proxy get generated using a factory method for the component...