ambiguous match found using t4mvc umbraco 6 and hijacking routes - Extending Umbraco

Kieron McIntyre 117 posts 360 karma points

Nov 22, 2013 @ 12:08

"Ambiguous match found" using T4MVC, Umbraco 6 and hijacking routes

In my current Umbraco 6 build, I am using T4MVC and when I hijack a route I get the following exception:

[AmbiguousMatchException: Ambiguous match found.]
   System.RuntimeType.GetMethodImpl(String name, BindingFlags bindingAttr, Binder binder, CallingConventions callConv, Type[] types, ParameterModifier[] modifiers) +11199352
   System.Type.GetMethod(String name) +28
   Umbraco.Web.Mvc.RenderActionInvoker.FindAction(ControllerContext controllerContext, ControllerDescriptor controllerDescriptor, String actionName) +100
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +100
   System.Web.Mvc.<>c__DisplayClass1d.b__19() +23
   System.Web.Mvc.Async.<>c__DisplayClass1.b__0() +19
   System.Web.Mvc.Async.<>c__DisplayClass8`1.b__7(IAsyncResult _) +10
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +62
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +57
   System.Web.Mvc.Async.<>c__DisplayClass4.b__3(IAsyncResult ar) +23
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +62
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +47
   System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +10
   System.Web.Mvc.<>c__DisplayClass8.b__3(IAsyncResult asyncResult) +25
   System.Web.Mvc.Async.<>c__DisplayClass4.b__3(IAsyncResult ar) +23
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +62
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +47
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9688704
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

I know what is causing it ... T4MVC creates a duplicate Index() which is confusing the Umbraco.Web.Mvc.RenderActionInvoker.FindAction() call since there are now two Index() actions. However, the T4MVC action is marked with the `[NonAction]` attributea dn s should be ignored by Umbraco's RendeActionInvoker - but it isn't.

But how do I fix this? The only thing I can think of is to introduce a custom RenderActionInvoker that ignores methods with such an attribute but then I would also need to override the default ControllerFactory too.

Any ideas? There must be projects using T4MVC in Umbraco successfully.

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Sebastiaan Janssen 5060 posts 15522 karma points MVP admin hq

Nov 22, 2013 @ 12:21

Sounds like it needs to be fixed in the core, created an issue : http://issues.umbraco.org/issue/U4-3675

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Kieron McIntyre 117 posts 360 karma points

Nov 22, 2013 @ 12:53

Ok, yes I have a solution but you have to:

Override the ControllerFactory with a new ControllerFactory that inherits from RenderControllerFactory
Create a new ControllerActionInvoker

So, in the global.asax:

protected override void OnApplicationStarted(object sender, EventArgs e)
{
    IControllerFactory factory = new CustomControllerFactory();
    ControllerBuilder.Current.SetControllerFactory(new CustomControllerFactory());
}

Using the following classes:

public class CustomControllerFactory : RenderControllerFactory
{
    public override IController CreateController(RequestContext requestContext, string controllerName)
    {
        var instance = base.CreateController(requestContext, controllerName);
        var controllerInstance = instance as Controller;
        if (controllerInstance != null)
        {
            controllerInstance.ActionInvoker = new CustomRenderActionInvoker();
        }

        return instance;
    }
}

and

public class CustomRenderActionInvoker : ControllerActionInvoker
{
    protected override ActionDescriptor FindAction(ControllerContext controllerContext, ControllerDescriptor controllerDescriptor, string actionName)
    {
        var ad = base.FindAction(controllerContext, controllerDescriptor, actionName);
        if (ad == null)
        {
            if (controllerContext.Controller is RenderMvcController)
            {
                return new ReflectedActionDescriptor(
                    controllerContext.Controller.GetType().GetMethods().First(x =>
                        x.Name == "Index" &&
                        !x.GetCustomAttributes(typeof(NonActionAttribute), false).Any()),
                    "Index",
                    controllerDescriptor
                );
            }
        }
        return ad;
    }
}

These are essentially just modified duplicates of what already exists in the Umbraco source.

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lucuma 261 posts 563 karma points

Feb 15, 2014 @ 21:51

Thanks for posting that code. The current documentation isn't valid in that this still (v7.0.3) generates an ambiguous error when following the guide with regards to route hijacking and inheriting form RenderModel.

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Kieron McIntyre 117 posts 360 karma points

Feb 25, 2014 @ 12:47

If you want to use this with the Hybrid framework (as I recently did), change the conditional line to read: