asp.net核心缺少javascript文件路由问题

Question

I'm facing an issue where any missing .js files are returned as a 200 ok result from the server and the content of the file is the markup of the _Layout.cshtml file. It makes sense since I'm using a catch-all route (we're developing a single page app) with a default action:

app.UseMvc(routes =>
{
    routes.MapRoute("default", "{controller=App}/{action=Index}");

    routes.MapRoute(
        name: "single-page",
        template: "{*url}",
        defaults: new {controller = "App", action = "Index"});
    });
}

So if I add a reference to the _Layout.cshtml for a file which doesn't exist, like this:

<script src="~/js/thisDoesntExist.js"></script>

I get the following result from the server:

Is there any way to tell my routing that if the physical file doesn't exist, then return a 404? :-)

Thanks in advance.

Answer 1

That is literally what catch-all means. It's going to catch every single thing and route it to AppController.Index , so everything is going to be a 200. No, there's nothing you can do about that. I mean, you could manually check if the URL maps to a physical file, and alternatively either manually return a 404 (if it doesn't exist) or a the file itself, but then you're taking over static file handling, which is going to be highly inefficient, and require a lot of extra logic to do properly (accounting for cache control, etc.).

You don't need a catch-all route just because you have a SPA. In fact, it would be better if you didn't, so all the static resources the SPA is going to rely on can be served more efficiently, and you can actually have things like API endpoints. As it is, there's not even a point to this being an ASP.NET Core application. You might as well just do a pure static site with an index.html.

Long and short, get rid of the catch-all route. Just have the default route be your main app landing page. That's all you need.