autofac / Autofac.Extras.DynamicProxy

Interceptor and decorator support for Autofac IoC via Castle DynamicProxy
MIT License
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Use proxy generator options "Selector" for interceptor selection #29

Open tillig opened 5 years ago

tillig commented 5 years ago

Based on this StackOverflow question it may be interesting to look at allowing the proxy generation options Selector influence the choice for interceptors.

tillig commented 3 years ago

Just for clarity and searchability, the sample code from the question which uses InterceptorSelector from the Castle library:

class Program
{
    static void Main(string[] args)
    {
        var builder = new ContainerBuilder();
        var proxyGenerationOptions = new ProxyGenerationOptions();

        //I want to use this
        //proxyGenerationOptions.Selector = new InterceptorSelector();

        builder.RegisterType<SomeType>()
            .As<ISomeInterface>()
            .EnableInterfaceInterceptors(proxyGenerationOptions)

            .InterceptedBy(typeof(CallLogger));//and remove explicit statement

        builder.Register<TextWriter>(x => Console.Out);

        builder.RegisterType<CallLogger>().AsSelf();

        var container = builder.Build();

        var willBeIntercepted = container.Resolve<ISomeInterface>();
        willBeIntercepted.Work();
    }
}

public class InterceptorSelector : IInterceptorSelector
{
    public IInterceptor[] SelectInterceptors(Type type, MethodInfo method, IInterceptor[] interceptors)
    {
        //don't know how to solve dependency here, because it's registration time
        return new IInterceptor[] { /* new CallLogger(dependency) or InterceptorReference.ForType<CallLogger>()  */};
    }
}

public class CallLogger : IInterceptor
{
    TextWriter _output;

    public CallLogger(TextWriter output)
    {
        _output = output;
    }

    public void Intercept(IInvocation invocation)
    {
        invocation.Proceed();

        _output.WriteLine("Done: result was {0}.", invocation.ReturnValue);
    }
}

public interface ISomeInterface { void Work(); }

public class SomeType : ISomeInterface { public void Work() { } }