How to change validation error responses in DRF?

Question

I want to change the JSON, which rest_framework or django returns when a validation error occures.

I will use one of my views as example, but I want to change error mess

Answer 1

if not serializer.is_valid(raise_exception=False)
    return Response(serializer.errors.values(), status=status.HTTP_400_BAD_REQUEST)

Answer 2

The default structure of DRF when handling errors is something like this:

{"email": ["This field is required."]}

And you can change this structure to your need by writing a custom exception handler.

Now let's say you want to achieve the following structure:

{"errors": [{"field": "email", "message": "This field is required."}]}

Your custom exception handler could be something like this:

from rest_framework.views import exception_handler


def custom_exception_handler(exc, context):
    # Call REST framework's default exception handler first,
    # to get the standard error response.
    response = exception_handler(exc, context)

    # Update the structure of the response data.
    if response is not None:
        customized_response = {}
        customized_response['errors'] = []

        for key, value in response.data.items():
            error = {'field': key, 'message': value}
            customized_response['errors'].append(error)

        response.data = customized_response

    return response

Answer 3

The easiest way to change the error style through all the view in your application is to always use serializer.is_valid(raise_exception=True), and then implement a custom exception handler that defines how the error response is created.