@jacobtylerwalls I'm not sure how to test this. I can see that we now have an endpoint at "api", but how would this be used in practice?

Sure thing. This came up in the controlled list manager work, where due to a bug the frontend was issuing malformed AJAX requests like:

A client might issue a malformed URL, e.g. api/controlledlists/1, which is malformed because 1 is not a UUID.

So you can visit any invalid api route like api/garbage and ensure you get JSON back instead of the Django debug page. JSON is obviously much easier to parse into an error message, see screenshots on #11166 of this working in a vue app.

So you can visit any invalid api route like api/garbage and ensure you get JSON back instead of the Django debug page. JSON is obviously much easier to parse into an error message, see screenshots on #11166 of this working in a vue app.

I tried this but got a 400 htm error page instead of JSON

I can't reproduce. Is there any additional information in the response?

I can only get a response like that if I have DEBUG=False and a bad value in ALLOWED_HOSTS.

But you don't need to test with DEBUG=False. Testing with DEBUG=True is easy because you can verify that you do not get the url debug view, but rather the route matches and returns JSON.