Using Django's prefetch_related on complex queries
I have the following basic query in my APIView:
categories = UserCategorizationType.objects.all() In the serializer, I have setup eager loading for all foreign keys and one-to-many relationships as well. However, now I need to setup eager lading for a field that is added by the serializer of UserCategorizationType. Basically, for each result in categories, I want to append a field called "possibleValues". I do this in my serializer like so:
class UserCategorizationTypeWithApprovedValuesSerialiser(BaseSerializer): possibleValues = serializers.SerializerMethodField() def get_possibleValues(self, categorizationType_): #-- get all approved values and user's own values values = UserCategorizationValue.objects.filter( Q(categorizationType=categorizationType_) & ( Q(categorizations__in=UserCategorization.objects.filter(author=self.__userProfile)) | Q(state="APPROVED") ) ).distinct() serializer = UserCategorizationValueSerializerValueOnly(values, many=True) return serializer.data My question is how do I use prefetch_related for this sort of query? I want this query to ideally stay in the serializer because there are multiple views that obtain categories and I want to encapsulate the way possibleValues are added into a category.
