200 – OK – Eyerything is working
201 – OK – New resource has been created
204 – OK – The resource was successfully deleted
304 – Not Modified – The client can use cached data
400 – Bad Request – The request was invalid or cannot be served. The exact error should be explained in the error payload. E.g. „The JSON is not valid“
401 – Unauthorized – The request requires an user authentication
403 – Forbidden – The server understood the request, but is refusing it or the access is not allowed.
404 – Not found – There is no resource behind the URI.
422 – Unprocessable Entity – Should be used if the server cannot process the enitity, e.g. if an image cannot be formatted or mandatory fields are missing in the payload.
500 – Internal Server Error – API developers should avoid this error. If an error occurs in the global catch blog, the stracktrace should be logged and not returned as response.