前言
當查詢出來的數據量非常大的時候，需要分頁查詢，django-rest-framework 提供了分頁的支持。
有三種分頁功能：PageNumberPagination，LimitOffsetPagination，CursorPagination。
分頁器
django-rest-framework 分頁器有三種：
- PageNumberPagination 簡單分頁（查看第n頁，每頁顯示N條）
- LimitOffsetPagination 偏移分頁（在第n個位置，向后查看n條數據）
- CursorPagination 加密分頁，只能看上一頁和下一頁，速度快
簡單分頁(PageNumberPagination)
我們可以在配置文件中設置全局的分頁方式, 這里設置簡單分頁(PageNumberPagination)，每頁顯示10條數據
REST_FRAMEWORK = {
'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination',
'PAGE_SIZE': 5 # 每頁數目
}
也可以自己重寫PageNumberPagination類，定義分頁方式
from rest_framework.pagination import PageNumberPagination
# 作者-上海悠悠 QQ交流群:717225969
# blog地址 https://www.cnblogs.com/yoyoketang/
class MyPageNumberPagination(PageNumberPagination):
page_size = 5 # 默認每頁顯示的多少條記錄
page_query_param = 'page' # 默認查詢參數名為 page
page_size_query_param = 'size' # 前台控制每頁顯示的最大條數
max_page_size = 20 # 后台控制顯示的最大記錄條數
PageNumberPagination類可以設置以下屬性
- page_size 數字，頁面顯示的記錄條數，不設置的就默認setting配置的全局PAGE_SIZE值
- page_query_param 字符串，查詢參數的名稱，不設置默認是'page'
- page_size_query_param 字符串，請求設置頁面大小的參數名稱，默認是None
- max_page_size 最大允許請求的頁面大小，僅在page_size_query_param被設置時有效
- last_page_string 字符串列表或元組，默認是 ('last',)
- template 分頁空間使用的模板名稱，可以覆蓋或設置為None，默認'rest_framework/pagination/numbers.html'
APIView使用分頁查詢
寫查詢視圖的時候，先序列化，再定義分頁器,查詢的時候可以帶上參數/api/v1/goods?page=1&size=10
from rest_framework import serializers
from .models import Goods
from rest_framework.pagination import PageNumberPagination
from rest_framework.permissions import IsAuthenticated, AllowAny
# 作者-上海悠悠 QQ交流群:717225969
# blog地址 https://www.cnblogs.com/yoyoketang/
# 序列化 Goods 模型
class GoodsAPISerializer(serializers.ModelSerializer):
class Meta:
model = Goods
fields = '__all__' # 返回全部的字段
# 定義分頁器簡單分頁(PageNumberPagination)
class MyPageNumberPagination(PageNumberPagination):
page_size = 5 # 默認每頁顯示的多少條記錄
page_query_param = 'page' # 默認查詢參數名為 page
page_size_query_param = 'size' # 前台控制每頁顯示的最大條數
max_page_size = 20 # 后台控制顯示的最大記錄條數
# 查詢視圖
class GoodsAPISView(APIView):
permission_classes = (AllowAny,) # AllowAny 允許所有用戶
def get(self, request, *args, **kwargs):
'''返回所有的'''
page = MyPageNumberPagination()
goods = Goods.objects.all() # 查詢全部
ret = page.paginate_queryset(goods, request)
serializer = GoodsAPISerializer2(ret, many=True)
return Response({
"code": 0,
"msg": "success!",
"data": serializer.data
})
分頁查詢
如果不帶參數，直接請求，會返回默認的 5 條數據http://localhost:8000/api/v1/goods
{
"code": 0,
"msg": "success!",
"data": [{
"id": 1,
"create_time": "2021-01-17 15:14:25",
"update_time": "2021-01-19 10:02:05",
"goodsname": "《selenium入門到精通3》",
"goodscode": "sp_100049",
"merchantid": "10001",
"merchantname": "悠悠學堂",
"goodsprice": 52.365,
"stock": 100,
"goodsgroupid": 0,
"goodsstatus": 1
}, {
"id": 13,
"create_time": "2021-01-16 20:12:36",
"update_time": "2021-01-17 09:41:05",
"goodsname": "《selenium入門到精通》",
"goodscode": "sp_100008",
"merchantid": "10001",
"merchantname": "悠悠學堂",
"goodsprice": 49.9,
"stock": 100,
"goodsgroupid": 0,
"goodsstatus": 1
}, {
"id": 14,
"create_time": "2021-01-16 20:12:42",
"update_time": "2021-01-17 09:41:05",
"goodsname": "《selenium入門到精通》",
"goodscode": "sp_100009",
"merchantid": "10001",
"merchantname": "悠悠學堂",
"goodsprice": 49.9,
"stock": 100,
"goodsgroupid": 0,
"goodsstatus": 1
}, {
"id": 101,
"create_time": "2021-01-16 21:24:10",
"update_time": "2021-01-17 09:41:05",
"goodsname": "",
"goodscode": "sp_10086",
"merchantid": "",
"merchantname": "",
"goodsprice": 0.0,
"stock": 0,
"goodsgroupid": 0,
"goodsstatus": 1
}, {
"id": 102,
"create_time": "2021-01-16 21:26:23",
"update_time": "2021-01-17 09:41:05",
"goodsname": "",
"goodscode": "sp_10087",
"merchantid": "",
"merchantname": "",
"goodsprice": 0.0,
"stock": 0,
"goodsgroupid": 0,
"goodsstatus": 1
}]
}
帶上 page 和 size 參數查詢,指定查詢的 page 頁數和 size 數量http://localhost:8000/api/v1/goods?page=1&size=2
{
"code": 0,
"msg": "success!",
"data": [{
"id": 1,
"create_time": "2021-01-17 15:14:25",
"update_time": "2021-01-19 10:02:05",
"goodsname": "《selenium入門到精通3》",
"goodscode": "sp_100049",
"merchantid": "10001",
"merchantname": "悠悠學堂",
"goodsprice": 52.365,
"stock": 100,
"goodsgroupid": 0,
"goodsstatus": 1
}, {
"id": 13,
"create_time": "2021-01-16 20:12:36",
"update_time": "2021-01-17 09:41:05",
"goodsname": "《selenium入門到精通》",
"goodscode": "sp_100008",
"merchantid": "10001",
"merchantname": "悠悠學堂",
"goodsprice": 49.9,
"stock": 100,
"goodsgroupid": 0,
"goodsstatus": 1
}]
}