drf 分页组件

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组件导入

   在drf中,拥有三种分页器,以下是三种分页器的导入:

from rest_framework.pagination import PageNumberPagination
from rest_framework.pagination import LimitOffsetPagination 
from rest_framework.pagination import CursorPagination

   第一种分页器非常常用,拥有上一页下一页,同时也可以做诸如1,2,3,4这样的@R_257_404@数。

   第二种分页器是游标分页器,它有一个基准点,你可以根据这个基准点进行左偏移和右偏移,相对使用较少。

   第三种分页器效率是最高的,只有上一页下一页,不可以做页数的跳转

使用方式

通用声明

   只需要在你的视图类中进行赋值即可。

from rest_framework.generics import ListAPIView
from rest_framework.pagination import PageNumberPagination
from rest_framework.pagination import LimitOffsetPagination
from rest_framework.pagination import CursorPagination

from app01.serializer import *
from app01 import models


class BookAPI(ListAPIView):
    queryset = models.Book.objects.filter(delete_status=False)  # 查询删除的数据
    serializer_class = BookModelSerializer
    pagination_class = PageNumberPagination  # 指定分页

全局配置

   在全局的settings.py下配置每页显示的个数:

#settings.py
REST_FRAMEWORK={
    'PAGE_SIZE': 2,# 每页显示的个数
}

详细配置

   如果需要针对不同的组件配置不同的设置,可以使用一个类来进行继承上面的分页组件,然后写详细的配置,如:

from app01.serializer import *
from app01 import models

class MyPage(PageNumberPagination):
    page_size = 3  # 每页条数
    page_query_param = 'page'  # url上跳转的的名称,默认为page
    page_size_query_param = 'size'  # 每一页显示的条数(前端可通过这个获取,覆盖后端给的固定条数),如后端给三条,前端请求时在url后带上size=9就代表老铁我要九条
    max_page_size = 5  # 每页最大显示条数

class BookAPI(ListAPIView):
    queryset = models.Book.objects.filter(delete_status=False)  # 查询删除的数据
    serializer_class = BookModelSerializer
    pagination_class = MyPage

ListAPIView

   分页只在获取所有时使用,所以我们直接使用generices下的ListAPIView

from rest_framework.generics import ListAPIView
from rest_framework.pagination import PageNumberPagination
from rest_framework.pagination import LimitOffsetPagination
from rest_framework.pagination import CursorPagination

from app01.serializer import *
from app01 import models

class MyPage(PageNumberPagination):
    page_size = 3  # 每页条数
    page_query_param = 'page'  # url上跳转的的名称,默认为page
    page_size_query_param = 'size'  # 每一页显示的条数(前端可通过这个获取,覆盖后端给的固定条数),如后端给三条,前端请求时在url后带上size=9就代表老铁我要九条
    max_page_size = 5  # 每页最大显示条数

class BookAPI(ListAPIView):
    queryset = models.Book.objects.filter(delete_status=False)  # 查询删除的数据
    serializer_class = BookModelSerializer
    pagination_class = MyPage

APIView

   如果你是使用APIView,则配置相对比较麻烦,如下示例:

from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework.pagination import PageNumberPagination
from rest_framework.pagination import LimitOffsetPagination
from rest_framework.pagination import CursorPagination

from app01.serializer import *
from app01 import models


class MyPage(PageNumberPagination):
    page_size = 3  # 每页条数
    page_query_param = 'page'  # url上跳转的的名称,默认为page
    page_size_query_param = 'size'  # 每一页显示的条数(前端可通过这个获取,覆盖后端给的固定条数),如后端给三条,前端请求时在url后带上size=9就代表老铁我要九条
    max_page_size = 5  # 每页最大显示条数


class BookAPI(APIView):
    def get(self,request,*args,**kwargs):
        book_list = models.Book.objects.all().order_by("pk")  # 使用APIView时,手动排序,否则会抛出warning

        # 实例化得到一个分页器对象
        page_cursor = MyPage()

        book_list = page_cursor.paginate_queryset(book_list,view=self)
        next_url = page_cursor.get_next_link()
        prev_url = page_cursor.get_prevIoUs_link()

        book_ser = BookModelSerializer(book_list,many=True)
        res_data = {
            "next_url": next_url,"prev_url": prev_url,"data": book_ser.data
        }

        return Response(data=res_data)

返回格式

PageNumberPagination

   使用案例:

from rest_framework.generics import ListAPIView
from rest_framework.pagination import PageNumberPagination
from rest_framework.pagination import LimitOffsetPagination
from rest_framework.pagination import CursorPagination

from app01.serializer import *
from app01 import models


class MyPage(PageNumberPagination):
    page_size = 3  # 每页条数
    page_query_param = 'page'  # url上跳转的的名称,默认为page
    page_size_query_param = 'size'  # 每一页显示的条数(前端可通过这个获取,覆盖后端给的固定条数),如后端给三条,前端请求时在url后带上size=9就代表老铁我要九条
    max_page_size = 5  # 每页最大显示条数


class BookAPI(ListAPIView):
    queryset = models.Book.objects.filter(delete_status=False)  # 查询删除的数据
    serializer_class = BookModelSerializer
    pagination_class = MyPage

   它的返回格式如下:

{
    "count": 17,# 代表后端还剩多少数据
    "next": "http://127.0.0.1:8000/api/books/?page=4","prevIoUs": "http://127.0.0.1:8000/api/books/?page=2","results": [
		{},{},]
}

LimitOffsetPagination

   使用案例:

from rest_framework.generics import ListAPIView
from rest_framework.pagination import PageNumberPagination
from rest_framework.pagination import LimitOffsetPagination
from rest_framework.pagination import CursorPagination

from app01.serializer import *
from app01 import models


class MyPage(LimitOffsetPagination):
    default_limit = 3  # 每页条数
    limit_query_param = 'limit'  # 往后拿几条
    offset_query_param = 'offset'  # 标杆
    max_limit = 5  # 每页最大几条


class BookAPI(ListAPIView):
    queryset = models.Book.objects.filter(delete_status=False)  # 查询删除的数据
    serializer_class = BookModelSerializer
    pagination_class = MyPage

   返回格式如下:

{
    "count": 17,"next": "http://127.0.0.1:8000/api/books/?limit=3&offset=6&page=3","prevIoUs": "http://127.0.0.1:8000/api/books/?limit=3&page=3",]
}
   

CursorPagination

   使用它的性能最高。但是只适用于数据量非常大的时候使用。

   使用案例:

from rest_framework.generics import ListAPIView
from rest_framework.pagination import PageNumberPagination
from rest_framework.pagination import LimitOffsetPagination
from rest_framework.pagination import CursorPagination

from app01.serializer import *
from app01 import models


class MyPage(CursorPagination):
    cursor_query_param = 'cursor'  # 每一页查询的key
    page_size = 2   # 每页显示的条数
    ordering = 'pk'  # 排序字段


class BookAPI(ListAPIView):
    queryset = models.Book.objects.filter(delete_status=False)  # 查询删除的数据
    serializer_class = BookModelSerializer
    pagination_class = MyPage

   返回格式:

{
    "next": "http://127.0.0.1:8000/api/books/?cursor=cD0xOQ%3D%3D","prevIoUs": null,]
}
原文链接:/django/994716.html

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