How to check if method has an attribute with Castle Interceptor?

Question

I am learning dependency injection and interception with Castle Windsor and WCF,and I would like to check if an intercepted method has a custom attribute (LogAttribute).

(My example is based on this answer : https://stackoverflow.com/a/2593091 )

Service contract :

[ServiceContract]
public interface IOrderService
{
    [OperationContract]
    Order GetOrder(int orderId);
}

[DataContract]
public class Order
{
    [DataMember]
    public string Id { get; set; }

    // [...]
}

Service implementation :

public class OrderService : IOrderService
{
    private readonly IDatabase _database;

    public OrderService(IDatabase database)
    {
        _database = database;
    }

    [Log] // <- my custom attribute
    public Order GetOrder(int orderId)
    {
        return _database.GetOrder(orderId);
    }
}

public class LogAttribute : Attribute
{ }

Simple data access layer :

public interface IDatabase
{
    Order GetOrder(int orderId);
}

public class Database : IDatabase
{
    public Order GetOrder(int orderId)
    {
        return new Order
        {
            Id = orderId
        };
    }
}

Dependency injection and interception :

public class Global : HttpApplication
{
    public static WindsorContainer Container { get; private set; }

    protected void Application_Start(object sender, EventArgs e)
    {
        BuildContainer();
    }

    private static void BuildContainer()
    {
        if (Container != null)
            return;

        Container = new WindsorContainer();

        Container.AddFacility<WcfFacility>();

        Container.Register(Component.For<IInterceptor>().ImplementedBy<MyInterceptor>().LifestyleTransient());
        Container.Register(Component.For<IDatabase>().ImplementedBy<Database>().LifestylePerWcfOperation());
        Container.Register(Component.For<IStringReverser>().ImplementedBy<StringReverser>().Interceptors<MyInterceptor>());
    }
}

public class MyInterceptor : IInterceptor
{
    public void Intercept(IInvocation invocation)
    {
        DoSomeWorkBefore(invocation);

        invocation.Proceed();
    }

    private static void DoSomeWorkBefore(IInvocation invocation)
    {
        if (Attribute.IsDefined(invocation.Method, typeof(LogAttribute)))
        {
            // This part of the code is never executed
            Debug.WriteLine("Method has Log attribute !");
        }
    }
}

I already tried invocation.Method.GetCustomAttributes and Attribute.GetCustomAttribute, but it does not find the LogAttribute. Any ideas ?

Answer 1

the (Windsor) service is for IOrderService interface and so invocation.Method will point to the method on the interface, which doesn't have the attribute.

use invocation.MethodInvocationTarget to get the class's method