Missing "errors" field in error response

[joeyespo]

The 400-level errors are responding with a JSON array containing error objects, but the JSON API spec requires a top-level error field.

To reproduce

1. Use serializer.is_valid(raise_exception=True) in an API view

2. Send invalid JSON from the client to any API endpoint

   Example:

   ajax({
     url: '/my/api',
     contentType: 'application/vnd.api+json',
     type: 'POST',
     data: 'not JSON'
   });

   Expected response:

   {
     "errors": [
       {
         "status": "400",
         "source": {"pointer": "/data"},
         "detail": "JSON parse error - No JSON object could be decoded"
       }
     ]
   }

   Actual response:

     [
       {
         "status": "400",
         "source": {"pointer": "/data"},
         "detail": "JSON parse error - No JSON object could be decoded"
       }
     ]

It seems like the exception handler is properly setting the resource name, which should be used here. The former gets called, but the latter does not. DRF seems to have taken over, responding with this project's exception_handler as-is.

My requirements

...
Django==1.9.1
djangorestframework==3.3.3
djangorestframework-jsonapi==2.0.0-beta.2
...

My config

REST_FRAMEWORK = {
    'DEFAULT_PERMISSION_CLASSES': (
        'rest_framework.permissions.IsAuthenticated',
    ),
    'DEFAULT_AUTHENTICATION_CLASSES': (
        'rest_framework.authentication.TokenAuthentication',
        'rest_framework.authentication.BasicAuthentication',
    ),
    'DEFAULT_RENDERER_CLASSES': (
        'rest_framework_json_api.renderers.JSONRenderer',
    ),
    'DEFAULT_PARSER_CLASSES': (
        'rest_framework_json_api.parsers.JSONParser',
        'rest_framework.parsers.FormParser',
        'rest_framework.parsers.MultiPartParser',
    ),
    'EXCEPTION_HANDLER': 'rest_framework_json_api.exceptions.exception_handler',
}

[jerel]

@joeyespo thanks for the detailed bug report. Did you end up finding a fix and would you like to open a PR? If not I'll try to get to it myself. I'm guessing that the issue has something to do with calling serializer.is_valid(raise_exception=True) manually rather than by the view itself.

[joeyespo]

@jerel Thanks for the reply! I did. I got something working locally for both this and #214. I'll open a PR within the next couple days.

[jerel]

@joeyespo good to hear! I did just merge a pull request (#222) that moves the error formatting to utils.py. Not much changed with the implementation but you'll want to pull that in before opening your PR

[joeyespo]

Ok. Rebased and opening the PR now. Feel free to rename any variables or completely change it.