class DeleteLedgerCategory(DestroyAPIView):
serializer_class = CategorySerializer
permission_classes = [IsAuthenticated]
def get_queryset(self):
queryset = Category.objects.filter(company = self.request.user.currently_activated_company, id=self.kwargs['pk'])
return queryset
def preform_destroy(self, instance):
if instance.is_default == True:
raise ValueError("Cannot delete default system category")
return instance.delete()
In above class based view. I need to add custom validation error message. ie. if instance.is_default == True: raise error... and only allow to delete the instance if no error encounters. If any unclear question. Do comment
Instead of just raise error you can customize response in destroy method:
from rest_framework.response import Response
class DeleteLedgerCategory(DestroyAPIView):
serializer_class = CategorySerializer
permission_classes = [IsAuthenticated]
def get_queryset(self):
queryset = Category.objects.filter(company = self.request.user.currently_activated_company, id=self.kwargs['pk'])
return queryset
def destroy(self, request, *args, **kwargs):
instance = self.get_object()
if instance.is_default == True:
return Response("Cannot delete default system category", status=status.HTTP_400_BAD_REQUEST)
self.perform_destroy(instance)
Try to override validate method of serializer,
class CategorySerializer(serializers.ModelSerializer):
class Meta:
model = Category
# fields
def validate_is_default(self, attrs):
if attrs['is_default '] is True
raise serializers.ValidationError("error message")
return attrs
and your views.py will be,
from rest_framework.response import Response
class DeleteLedgerCategory(DestroyAPIView):
serializer_class = CategorySerializer
permission_classes = [IsAuthenticated]
def get_queryset(self):
queryset = Category.objects.filter(company=self.request.user.currently_activated_company, id=self.kwargs['pk'])
return queryset
def preform_destroy(self, instance):
serializer = CategorySerializer(data=self.get_queryset())
serializer.is_valid(True)
return instance.delete()
