DRF 排序-过滤-分页

1 排序

ordering

# 对价格进行升序排序
# http://127.0.0.1:8008/app01/books/?ordering=price
# 对价格进行降序排序
# http://127.0.0.1:8008/app01/books/?ordering=-price

from rest_framework.filters import OrderingFilter

class BookView(GenericViewSet,ListAPIView):
    filter_backends = [OrderingFilter]
    ordering_fields = ['price']

• 必须是继承 GenericAPIView 的视图类
• 定制返回格式--》重写list--》重写了lis
  • 如果纯自己写了：不生效了
  • 如果还是使用父类的list方法：生效
  • 半自己写：只要有他就会生效 self.filter_queryset()

2 过滤

内置的----模糊匹配

search

# 加过滤：名字中只要带梦，都能查出来：
# http://127.0.0.1:8008/app01/books/?search=梦

from rest_framework.filters import SearchFilter
class BookListView(GenericViewSet,ListModelMixin):
    filter_backends = [SearchFilter]
    # 也可以多个字段模糊匹配
    search_fields=['name','publish']

第三方过滤----精准匹配

# 查询价格为66的图书
# http://127.0.0.1:8008/app01/books/?price=66
# 查询价格为66的图书 并且名字为 红楼梦 的图书
# http://127.0.0.1:8008/app01/books/?price=66&name=红楼梦

class BookListView(GenericViewSet, ListModelMixin):
    filter_backends = [DjangoFilterBackend]
    filterset_fields = ['price', 'name']

自定义过滤类

filter.py

from rest_framework.filters import BaseFilterBackend
from django.db.models import Q

class CommonFilter(BaseFilterBackend):
    def filter_queryset(self, request, queryset, view):
        price = request.query_params.get('price', None)
        name = request.query_params.get('name', None)
        if price and name:
            queryset = queryset.filter(Q(price=price) | Q(name__contains=name))
        if price:
            queryset=queryset.filter(price=price)
        if name:
            queryset = queryset.filter(name__contains=name)

        return queryset

views.py

# 查询价格为66 或者 名字中包含红的数据
# http://127.0.0.1:8008/app01/books/?price=66&name=红
class BookListView(GenericViewSet, ListModelMixin):
    filter_backends = [SearchFilter,CommonFilter]
    search_fields = ['name', 'publish']

3 分页

pagination.py

基本分页

# http://127.0.0.1:8008/app01/books/?page=2&size=3
from rest_framework.pagination import PageNumberPagination

class CommonPageNumberPagination(PageNumberPagination):
    
    page_size = 2  # 每页显示2条
    page_query_param = 'page' 
    page_size_query_param = 'size' 
    max_page_size = 10  #  每页最多显示10条

偏移分页

# 从第3条开始，取1条
# http://127.0.0.1:8008/app01/books/?offset=3&limit=1 

class CommonLimitOffsetPagination(LimitOffsetPagination):
    default_limit = 2 # 每页显示两条
    limit_query_param = 'limit' # 控制每页显示多少条
    offset_query_param = 'offset' # 偏移量
    max_limit = 10  # 最大每页取10条

游标分页

• 必须要排序
• 只能取上一页和下一页，不能直接跳转到某一页
• 效率高， 大数据量 app端使用

from rest_framework.pagination import CursorPagination

class CommonCursorPagination(CursorPagination):
    cursor_query_param = 'cursor' # 查询条件 
    page_size = 2  # 每页显示两条
    ordering = 'id' # 按什么排序，需要指定

views.py

• 分页方式只能选择一种

class BookListView(GenericViewSet, ListModelMixin):
    queryset = Book.objects.all()
    serializer_class = BookSerializer
    permission_classes = []
    throttle_classes = []
    # 普通分页
    # pagination_class = CommonPageNumberPagination 
    # 偏移分页
    # pagination_class = CommonLimitOffsetPagination 
    # 游标分页
    pagination_class = CommonCursorPagination