Web API 2 Attribute Routing Not Working in 4.5 WebForms Project

Question

I've seen many other questions that are similar to my title but none seem to be same issue or supply insight that I need.

I've added a Web API Controller to an existing, legacy 4.5 WebForms application and am trying to get it working with minimal changes to existing code base. So I don't have the typical static WebApiConfig class and other default created items when you create project from scratch. My existing code base is:

Global.asax

protected void Application_Start( Object sender, EventArgs e ) 
{ 
    GlobalConfiguration.Configure( config =>
    {
        config.MapHttpAttributeRoutes();

        config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{id}",
            defaults: new
            {
                id = RouteParameter.Optional
            }
        );
    } );
}

Controller

namespace Modeler.Endpoints
{
    public class KatAppEndpoints : ApiController
    {
        [HttpGet]
        [Route( "api/katapp/calculations" )]
        public IEnumerable<string> GetCalculations()
        {
            return new string[] { "value1", "value2" };
        }
    }
}

Javascript

$(document).ready(function() {
    $.getJSON("api/katapp/calculations")
        .done(function () { debugger; })
        .fail(function (_jqXHR, errorStatus, errorMessage) { debugger; })
        .always(function () { debugger; });
});

When called, I hit the fail and always and the result is:

errorStatus: "error"
errorMessage: "Not Found"

Anything obvious I'm missing?

Update

If instead I change my Controller to...

namespace Modeler.Endpoints
{
    public class KatAppsController : ApiController
    {
        public IEnumerable<string> Get()
        {
            return new string[] { "value1", "value2" };
        }
    }
}

And my javascript to:

$.getJSON("api/katapps")
    .done(function () { debugger; })
    .fail(function (_jqXHR, errorStatus, errorMessage) { debugger; })
    .always(function () { debugger; });

Things work correctly. However, I have a handful of endpoints and wanted to use Attributes, but maybe I'll give up on that if I can figure out how to get another portion in the url (ie the /calculations part from above).

Answer 1

Not sure why, but this comment pointed me in the right spot: https://stackoverflow.com/a/38130308/166231

So even though I want to use attribute routing and might not be close to what controller name is, I still have to end the class name with *Controller . After renaming KatAppEndpoints to KatAppEndpointsController , everything worked.