Simple Django REST API

django_rest_api.py

from django.http import HttpResponse


class ApiResponse(HttpResponse):

    def __init__(data, **kwargs):
        kwargs.setdefault("content_type", "application/json")
        content = json.dumps(data)
        super(ApiResponse, self).__init__(content=data, **kwargs)


class ApiException(Exception):

    def __init__(self, message, status=400):
        self.message = message
        self.status = status

    def to_response(self):
        return ApiResponse({"message": self.message}, status=self.status)


class ApiMiddleWare(object):

    def process_exception(request, exception):
        if instanceof(ApiException, exception):
            return exception.to_response()
        else:
            return None


def add_numbers(request):
    a = request.GET.get("a", None)
    b = request.GET.get("b", None)
    result = {"sum": a + b}
    return ApiResponse(result)