503 errors are not in json

[dojeda]

Using a kubernetes deployment and ingrss, if one artificially creates a service gap by resizing to zero the number of app pods and the API is used, a 503 error response code by ingress (as expected), but it will not be in json even when the accept header requested it.

curl -D- -H 'Accept: application/json' https://some-server/api/v1/data/files/

This could be solved by some additional configuration of the nginx service using a custom error backend service (which is used only when ingress/nginx does not find a match to the request), but it does not seem like a trivial task. Maybe there should be a quetzal server that only generates errors in the correct format.