How to handle errors in API?

[pontus]

How do we want to handle errors from the API, e.g. signal through HTTP codes (e.g. 403), an empty answer or always do json with a status that is always filled in?

[HenrikeW]

When working on the frontend, I think it's really helpful to get proper status codes for different types of errors. When I'm still working on the code, I also appreciate if there is some error message sent in the json response that indicates what went wrong. That's more for my own purpose though. I don't show these API-messages to the user but rather have a separate message to the user in the frontend-code. That can be due to language reasons (API sends message in English, website is in Swedish) or because I want to phrase it in a nicer/more helpful way.

[pontus]

Yes, this was probably unclear.

Right now, I think there's a mix; some endpoints return errors akin to jsonapi, some set the return code indicating error on error or return value and some return an empty/null JSON object on error (but a 200). There should definitely be sensible return codes, no matter how we pass them.

[jhagberg]

Refactor standardize the way error propagation in backend,