OK it's not that funny an ending...
I am trying to emulate a RoR-based service in .Net WebAPI. The Ruby implementation of the service is supposed to return a JSON document from a url of:
http://myserver/api/assessments/{id}.js
Note the .js at the end.
I made a RouteAttribute decoration on my api controller like so:
[Route("~/api/assessments/{id}.js")]
public async Task<HttpResponseMessage> GetAssessment(int id)
{
    . . .
}
...but I'm getting a 404 error.  I suspected this might be because the request ended in "js", so after a bit of research I found I should set my RouteCollection.RouteExistingFiles to true... this did not seem to have any effect.  I am still getting 404.
Am I right?  is the .js ending what is causing the 404?  How can I get around this?  This is a pure WebApi project, so it's not like I'm using JavaScript in it anyway.
 
     
    