Django Rest Framework: serializer response error

Question

i have a problem with my viewset in DRF:

def get_queryset(self):
    """
    :return: filtered queryset based on request query_param

    """
    # todo#amedeo: improve the readability code
    qs = super(ChecklistViewSet, self).get_queryset()
    _pk = self.kwargs['pk']

    if self.request.method == 'PUT':
        instance = qs.filter(pk=int(_pk)).first()
        # pass in the instance we want to update
        serializer = ChecklistSerializer(instance, self.request.data)

        # validate and update
        if serializer.is_valid():
            serializer.save()
            serializer_dict = serializer.data
            serializer_dict["message"] = "Checklist updated successfully."
            return response.Response(serializer_dict, status=status.HTTP_200_OK)

        else:
            return response.Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

in my code the objetc was saved, but the response give an error that say:

AttributeError: 'Response' object has no attribute 'model'

My serializer is:

class ChecklistSerializer(serializers.ModelSerializer):

class Meta:
    model = Checklist
    fields = ('id', 'approved_by', 'role', 'hardship_classification',
              'total_capacity', 'capacity_for_residents', 'checklist_type',
              'state', 'pdf', 'submitting_afp', 'disabled', 'location')

i call by client PUT method passing json:

{
"approved_by": "Test",
"role": "test_role_4",
"hardship_classification": "test_6",
"total_capacity": "50",
"capacity_for_residents": "350",
"checklist_type": "permanent",
"state": "qcl_draft",
"pdf": null,
"submitting_afp": 3999,
"disabled": false,
"location": 97
}

but i receved that Error. The model was saved but Response give me the Error

Internal Server Error: /api/v1/checklists/3/ Traceback (most recent call last): File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/django/core/handlers/exception.py", line 41, in inner response = get_response(request) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 187, in _get_response response = self.process_exception_by_middleware(e, request) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 185, in _get_response response = wrapped_callback(request, *callback_args, **callback_kwargs) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view return view_func(*args, **kwargs) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/rest_framework/viewsets.py", line 116, in view return self.dispatch(request, *args, **kwargs) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/rest_framework/views.py", line 495, in dispatch response = self.handle_exception(exc) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/rest_framework/views.py", line 455, in handle_exception self.raise_uncaught_exception(exc) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/rest_framework/views.py", line 483, in dispatch self.initial(request, *args, **kwargs) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/rest_framework/views.py", line 401, in initial self.check_permissions(request) File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/rest_framework/views.py", line 334, in check_permissions if not permission.has_permission(request, self): File "/home/adifilippo/.envs/accomodation/local/lib/python2.7/site-packages/rest_framework/permissions.py", line 206, in has_permission perms = self.get_required_permissions(request.method, queryset.model) AttributeError: 'Response' object has no attribute 'model' "PUT /api/v1/checklists/3/ HTTP/1.1" 500 42934

enter code here

Answer 1

the get_queryset method should return the queryset not Response and the update action should be overrided in the put method. Read here class-based-views and filtering for more details. May be you need to remove the get_queryset overriding and just add the put method somethig like this:

def put(self, request, pk, format=None):
    instance = self.get_object(pk)
    # pass in the instance we want to update
    serializer = ChecklistSerializer(instance, self.request.data)

    # validate and update
    if serializer.is_valid():
        serializer.save()
        serializer_dict = serializer.data
        serializer_dict["message"] = "Checklist updated successfully."
        return response.Response(serializer_dict, status=status.HTTP_200_OK)

    else:
        return response.Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

Answer 2

you can do this

from django.shortcuts import get_objects_or_404

class YourAPIView(ModelViewSet):
   def put(self, request, pk):
       instance = get_objects_or_404(YourModel, pk=pk)
       serializer = ChecklistSerializer(instance, self.request.data)

# validate and update
       if serializer.is_valid():
           serializer.save()
           serializer_dict = serializer.data
           serializer_dict["message"] = "Checklist updated successfully."
           return response.Response(serializer_dict, status=status.HTTP_200_OK)
       return response.Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)