OnActionExecuted being called twice in Web API

Question

I am trying to do some stuff after my controller is done with the action at OnActionExecuted. However the method is called twice.

My filter method

public class TestFilter: ActionFilterAttribute
{
  public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
    {

       //do stuff here


    }
}

and my controller

[TestFilter]
  public class BaseController : ApiController
{
 public LoginResponseDTO Login(LoginRequestDTO loginRequestDTO)
    {

 //do login stuff
    }

}

when i try this filter, the onActionExecuted Method gets called twice which causes my action in the method to be applied twice to the response. I have searched for a reason but cannot find a solution.

Any Ideas?

Answer 1

The answer is from @Martijn comments above:

 [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, AllowMultiple = false, Inherited = true)]
 public class TestFilter: ActionFilterAttribute

All credits goes to him. (Note: I'll remove the post, if he decide to add the comment as answer)

Answer 2

For me the issue was I was calling /myApi/action which was redirecting to /myApi/action/ and this caused OnActionExecuted() to run twice.

I filtered out where filterContext.Result is RedirectResult within OnActionExecuted since I wasn't interested in running my code then. The HTTP status code showed as 200 on both the calls so filtering by that won't work.

Answer 3

If you have registered the custom filter in Global.asax.cs, like this:

GlobalConfiguration.Configuration.Filters.Add(new TestFilterAttribute());

Please revoke the attribute above your custom controller.