장고 generics crud 정리

github.com/encode/django-rest-framework/blob/master/rest_framework/mixins.py

encode/django-rest-framework

를 기준으로 알아보자

 

1. RetrieveModelMixin

class RetrieveModelMixin:
    """
    Retrieve a model instance.
    """
    def retrieve(self, request, *args, **kwargs):
        instance = self.get_object()
        serializer = self.get_serializer(instance)
        return Response(serializer.data)

에서 첫번째 줄 

instance = self.get_object()가 실행되면 

TblistRecommend object (38) 가 리턴된다 

 

마찬가지로 get_queryset()도 (docs.djangoproject.com/en/3.1/ref/class-based-views/mixins-single-object/)

 

- get_object는 (velog.io/@jcinsh/RetrieveUpdateDestroyView-%EC%9D%B4%ED%95%B4)

• queryset과 pk값을 인자로 받아서,
• queryset.filter(pk=pk)로 queryset을 뽑고,
• obj = queryset.get()으로 객체만 뽑아서 리턴해 주는 메소드임
  => 결국, 위 코드는 Customer.objects.get(pk=pk) 리턴함

- get_serializer는

• instance을 인자로 받아서, 해당 객체을 serialize해 주는 메소드임

get_object(queryset=None)¶
Returns the single object that this view will display. If queryset is provided, that queryset will be used as the source of objects; otherwise, get_queryset() will be used. get_object() looks for a pk_url_kwarg argument in the arguments to the view; if this argument is found, this method performs a primary-key based lookup using that value. If this argument is not found, it looks for a slug_url_kwarg argument, and performs a slug lookup using the slug_field.

When query_pk_and_slug is True, get_object() will perform its lookup using both the primary key and the slug.

 

get_queryset()¶

Returns the queryset that will be used to retrieve the object that this view will display. By default, get_queryset() returns the value of the queryset attribute if it is set, otherwise it constructs a QuerySet by calling the all() method on the model attribute’s default manager.

 

def get_object(self, queryset=None):
        """
        Returns the object the view is displaying.

        By default this requires `self.queryset` and a `pk` or `slug` argument
        in the URLconf, but subclasses can override this to return any object.
        """
        # Use a custom queryset if provided; this is required for subclasses
        # like DateDetailView
        if queryset is None:
            queryset = self.get_queryset()

        # Next, try looking up by primary key.
        pk = self.kwargs.get(self.pk_url_kwarg, None)
        slug = self.kwargs.get(self.slug_url_kwarg, None)
        if pk is not None:
            queryset = queryset.filter(pk=pk)

        # Next, try looking up by slug.
        if slug is not None and (pk is None or self.query_pk_and_slug):
            slug_field = self.get_slug_field()
            queryset = queryset.filter(**{slug_field: slug})

        # If none of those are defined, it's an error.
        if pk is None and slug is None:
            raise AttributeError("Generic detail view %s must be called with "
                                 "either an object pk or a slug."
                                 % self.__class__.__name__)

        try:
            # Get the single item from the filtered queryset
            obj = queryset.get()
        except queryset.model.DoesNotExist:
            raise Http404(_("No %(verbose_name)s found matching the query") %
                          {'verbose_name': queryset.model._meta.verbose_name})
        return obj   # Customer.object.get(pk=pk) 의미

# get_serializer 소스 코드

 def get_serializer(self, instance=None, data=None,
                       files=None, partial=False):
        """
        Return the serializer instance that should be used for validating and
        deserializing input, and for serializing output.
        """
        serializer_class = self.get_serializer_class()
        context = self.get_serializer_context()
        return serializer_class(instance, data=data, files=files,
                                partial=partial, context=context)

 

www.django-rest-framework.org/api-guide/serializers/#accessing-the-initial-data-and-instance

Serializers - Django REST framework

 

velog.io/@jcinsh/DRF-14-DRF-%EA%B3%B5%EC%8B%9D%EB%AC%B8%EC%84%9C-%EC%9A%94%EC%95%BD

DRF 14 - DRF 공식문서 요약