Django Rest 框架 - APIView 分页

Question

我有一个非常简单的APIView，但我不知道如何在这里设置分页。 在这种情况下，我选择一个带有给定pk 的Event，然后我将所有NewsItems 分配给这个Event。

pagination_class = LimitOffsetPagination 在ListCreateAPIView 开头定义查询集时工作正常，例如。 queryset = Event.objects.all() 但不是自定义get：

class EventNewsItems(APIView):
    pagination_class = LimitOffsetPagination

    def get(self, request, pk, format=None):

        #user = request.user
        event = Event.objects.get(pk=pk)
        news = event.get_news_items().all()

        serializer = NewsItemSerializer(news, many=True, context={'request':request})
        response = Response(serializer.data, status=status.HTTP_200_OK)
        return response

---

已解决：

def get(self, request, pk, format=None):

    #user = request.user
    event = Event.objects.get(pk=pk)
    news = event.get_news_items().all()
    paginator = LimitOffsetPagination()
    result_page = paginator.paginate_queryset(news, request)
    serializer = NewsItemSerializer(result_page, many=True, context={'request':request})
    response = Response(serializer.data, status=status.HTTP_200_OK)
    return response

Answer 1

另一个选项是从分页类继承，对视图类的更改更少：

from rest_framework.pagination import LimitOffsetPagination

class EventNewsItems(APIView, LimitOffsetPagination):

    def get(self, request, pk, format=None):
        event = Event.objects.get(pk=pk)
        news = event.get_news_items().all()

        results = self.paginate_queryset(news, request, view=self)
        serializer = NewsItemSerializer(results, many=True)
        return self.get_paginated_response(serializer.data)

Answer 2

我已经为此主题创建了Q&A style example。
作为排序摘要：

通过利用 Django Rest Frameworks 源代码以及它们如何处理分页，我们在视图类中创建相同的方法并使用它们，就像您的解决方案使用默认方法一样：

取自上述文档：

from rest_framework.settings import api_settings
from rest_framework.views import APIView

class MyView(APIView):
    queryset = OurModel.objects.all()
    serializer_class = OurModelSerializer
    pagination_class = api_settings.DEFAULT_PAGINATION_CLASS # cool trick right? :)

    # We need to override get method to achieve pagination
    def get(self, request):
        ...
        page = self.paginate_queryset(self.queryset)
        if page is not None:
            serializer = self.serializer_class(page, many=True)
            return self.get_paginated_response(serializer.data)

        ... Do other stuff needed (out of scope of pagination)

    # Now add the pagination handlers taken from 
    #  django-rest-framework/rest_framework/generics.py

    @property
    def paginator(self):
        """
        The paginator instance associated with the view, or `None`.
        """
        if not hasattr(self, '_paginator'):
            if self.pagination_class is None:
                self._paginator = None
            else:
                self._paginator = self.pagination_class()
        return self._paginator

     def paginate_queryset(self, queryset):
         """
         Return a single page of results, or `None` if pagination is disabled.
         """
         if self.paginator is None:
             return None
         return self.paginator.paginate_queryset(queryset, self.request, view=self)

     def get_paginated_response(self, data):
         """
         Return a paginated style `Response` object for the given output data.
         """
         assert self.paginator is not None
         return self.paginator.get_paginated_response(data) 

Answer 3

另一种分页方法是使用 Paginator 类。

除了答案查询，还必须设置要显示的页数和页面将包含的元素范围。

页码和项目范围可以作为请求参数的一部分提供，也可以通过您选择的方式提供。

以问题的情况为例：

from django.core.paginator import Paginator

class EventNewsItems(APIView):

    def get(self, request, pk, format=None):

        #user = request.user
        event = Event.objects.get(pk=pk)
        news = event.get_news_items().all()

         # -----------------------------------------------------------
        page_number = self.request.query_params.get('page_number ', 1)
        page_size = self.request.query_params.get('page_size ', 10)

        paginator = Paginator(news , page_size)
        serializer = NewsItemSerializer(paginator.page(page_number) , many=True, context={'request':request})
        # -----------------------------------------------------------

        response = Response(serializer.data, status=status.HTTP_200_OK)
        return response