[DRF]Detail Page 구현

✅ 목표

• 현재 게시글, 이전 게시글, 다음 게시글, 댓글로 detail page 구현

✅ 기존 코드

# views.py
class PostRetrieveListAPIView(RetrieveAPIView):
    queryset = Post.objects.all()
    serializer_class = PostRetrieveSerializer 

# serializers.py
class PostRetrieveSerializer(serializers.ModelSerializer):
    class Meta:
        model = Post
        exclude = ['create_dt'] # 'create_dt' 외 모든 데이터 전송

✔ 현재 게시글, 이전 게시글, 다음 게시글, 댓글 key 추가

# serializers.py
class PostSerializerSub(serializers.ModelSerializer):
    class Meta:
        model = Post
        fields = ['id', 'title']

class CommentSerializerSub(serializers.ModelSerializer):
    class Meta:
        model = Comment
        fields = ['id', 'content', 'update_dt']

class PostSerializerDetail(serializers.Serializer):
    post = PostRetrieveSerializer()
    prevPost = PostSerializerSub()
    nextPost = PostSerializerSub()
    commentList = CommentSerializerSub(many=True)

# views.py
def get_prev_next(instance):
    try:
        prev = instance.get_previous_by_update_dt() # Django 기본 메서드
    except instance.DoesNotExist:
        prev = None

    try:
        next_ = instance.get_next_by_update_dt() # Django 기본 메서드
    except instance.DoesNotExist:
        next_ = None
    
    return prev, next_


class PostRetrieveListAPIView(RetrieveAPIView):
    queryset = Post.objects.all()
    serializer_class = PostSerializerDetail

    def retrieve(self, request, *args, **kwargs):
        instance = self.get_object()
        prevInstance, nextInstance = get_prev_next(instance)
        commentList = instance.comment_set.all()
        data = {
            'post': instance,
            'prevPost': prevInstance,
            'nextPost': nextInstance,
            'commentList' : commentList,

        }
        serializer = self.get_serializer(instance = data)
        return Response(serializer.data)

PostRetrieveListAPIView

RetrieveAPIView > RetrieveModelMixin 참고.

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)

get_previous_by_update_dt(), get_next_by_update_dt()

두 메서드를 사용할 때는 exception 처리를 해야하기 때문에 별도로 get_prev_next 함수를 만들었다. 공식문서 참고.

✔ 결과