How to check attribute of action from HttpRequest - asp.net-mvc-3

Question

I've followed this Prevent Forms authentication in order to try and handle redirecting from ajax gracefully. However I need to be able to determine if certain attributes are decorating the action that this call was made for as I only want to do this for some occasions. Can I get this information from the HttpRequest object that is accessible within this method?.
Essentially taking the part from the code above that I would like to manipulate:
public class SuppressFormsAuthenticationRedirectModule : IHttpModule {
private void OnPostReleaseRequestState(object source, EventArgs args) {
var context = (HttpApplication)source;
var response = context.Response;
var request = context.Request; // request is HttpRequest
if (response.StatusCode == 401 && request.Headers["X-Requested-With"] ==
"XMLHttpRequest") {
// TODO HERE: Check that the controller action contains a particular attribute
// and if so do not suppress redirect
SuppressAuthenticationRedirect(context.Context);
}
}
}
UPDATE:
It's probably worth noting that this code is held within a compiled DLL project that is then encorporated into a host MVC application (which we don't have access to). In that case I don't really have access to changing default implementations unless I can ensure it doesn't effect the rest of the controllers in the application.

Answer 1

I tried to use as much of the framework as possible, which is why I chose to expose the GetControllerType method from the DefaultControllerFactory. You'll notice that routeData contains the area, controller and action, so with a bit of reflection, you can bypass having to create a derived controller factory.
This is definitely not production ready. It is just a way to get the custom attributes from the requested action.
Edit: instead of setting the current controller factory, create a new DerivedControllerFactory
var httpApplication = (HttpApplication)sender;
var httpContext = new HttpContext(httpApplication.Request, new HttpResponse(new StringWriter()));
var routeData = RouteTable.Routes.GetRouteData(new HttpContextWrapper(httpContext));
//var factory = ControllerBuilder.Current.GetControllerFactory() as DerivedControllerFactory;
var factory = new DerivedControllerFactory();
var controllerType = factory.GetControllerType(new RequestContext(new HttpContextWrapper(httpContext), routeData), routeData.Values["controller"].ToString());
var methodInfo = controllerType.GetMethod(routeData.Values["action"].ToString());
var attributes = methodInfo.GetCustomAttributes(true);
public class DerivedControllerFactory : DefaultControllerFactory
{
public new Type GetControllerType(RequestContext requestContext, string controllerName)
{
return base.GetControllerType(requestContext, controllerName);
}
}