八、分页

8.1 pageNumber分页

• 基本的分页功能

• utils/pagination.py：定义分页器类的属性值

  from rest_framework.pagination import PageNumberPagination
  
  
  class MyPagination(PageNumberPagination):
      """
      基本分页
      url?page=1&size=2
          每页2条，第1页
      """
      page_size = 1
      page_query_param = "page"
      page_size_query_param = "size"
      max_page_size = 3
             
  

8.2 limitOffset分页

• 从某个位置开始，取多少条数据

• utils/pagination.py：定义分页器类的属性值

  from rest_framework.pagination import LimitOffsetPagination
  
  
  class MyPagination(LimitOffsetPagination):
      """
      从特定位置开始查询数据
      url?limit=2&offset=3
          从第2条数据开始，往后找3条数据
      """
      default_limit = 1  # 设置默认向后找1条
      limit_query_param = "limit"
      offset_query_param = "offset"
      max_limit = 5  # 最大数据限制
  
  

8.3 Cursor分页

• 游标分页，对游标加密

• utils/pagination.py：定义分页器类的属性值

  from rest_framework.pagination import CursorPagination
  
  
  class MyPagination(CursorPagination):
      """
      游标分页
      url?cursor=加密游标
      """
      cursor_query_param = "cursor"
      page_size = 2
      ordering = "-id"  # 排序规则
  
  

8.4 视图

• views.py

  from rest_framework.views import APIView
  from utils.pagination import MyPagination
  
  
  class BookView(APIView):
  
      def get(self, request):
          queryset = Book.objects.all()
          # 1 实例化分页器对象
          page_obj = MyPagination()
          # 2 对queryset分页
          page_queryset = page_obj.paginate_queryset(queryset, request, view=self)
          # 3 把分页好的数据序列化返回
          ser_obj = BookSerializer(page_queryset, many=True)
          return page_obj.get_paginated_response(ser_obj.data)
          
  

8.5 视图（利用框架）

• views.py

  from utils.pagination import MyPagination
  from rest_framework.generics import GenericAPIView
  from rest_framework.mixins import ListModelMixin
  
  
  class BookView(GenericAPIView, ListModelMixin):
      queryset = Book.objects.all()
      serializer_class = BookSerializer
      pagination_class = MyPagination  # 配置分页器对象
  
      def get(self, request):
          # list方法中实现了分页逻辑
          return self.list(request)