django rest framework 分頁
DRF提供了3種分頁方式
基礎分頁:PageNumberPagination(夠用,常用,採用該方法)
Offset分頁類:LimitOffsetPagination(偏移量查詢分頁)
加密分頁:CursorPagination(只能通過點“上一頁”和下一頁訪問數據)
新建自定義分頁pager.py文件
基礎分頁
from rest_framework.pagination import PageNumberPagination, LimitOffsetPagination, CursorPagination
from rest_framework.response import Response
'''
自定義分頁:基礎分頁
http://127.0.0.1:8000/api/v1/work_order?size=10&page=1
'''
class MyPagination(PageNumberPagination):
# 指定每一頁的個數,默認爲配置文件裏面的PAGE_SIZE,也可以在settings.py中添加全局配置('PAGE_SIZE': 10 )
page_size = 10
# 可以讓前端指定每頁個數,指定size做爲key顯示每頁個數,可自定義key
page_size_query_param = 'size'
# 控制每頁最大顯示條數:(這個控制僅限制於路徑後拼接設置size=1000後,對其進行限制)
max_page_size = 100
# 可以讓前端指定頁碼數,默認是page做爲key顯示頁數,可自定義key
page_query_param = 'page'
# # 指定返回格式,根據需求返回一個總頁數,數據存在results字典裏返回
# def get_paginated_response(self, data):
# from collections import OrderedDict
# return Response(OrderedDict([('count', self.page.paginator.count), ('data', data)]))
在方法中調用基礎分頁
def get(self, request):
# 自定義response result,用於前後端分離
result = {'count': '', 'data': '', 'meta': {'msg': 'OK', 'status': 200}}
try:
# 基本分頁
workorder = WorkOrderInfo.objects.all().order_by('id')
count = WorkOrderInfo.objects.count()
# 創建對象
pg = MyPagination()
# 獲取分頁數據
page_query = pg.paginate_queryset(queryset=workorder, request=request, view=self)
# 序列化數據
workorder_ser = WorkOrderSerializer(page_query, many=True)
result['data'] = workorder_ser.data
result['count'] = count
except Exception as e:
result['meta']['msg'] = '獲取數據失敗'
result['meta']['status'] = 500
return Response(result)
這裏展示第1頁,每頁2條
Offset分頁
'''
自定義分頁:Offset分頁類
PS:http://127.0.0.1:8000/api/v1/work_order?limit=10&offset=20
'''
class MyLimitOffsetPagination(LimitOffsetPagination):
# 默認從offset偏移位置往後取幾個
default_limit = 10
# 每頁可顯示的條數,可自定義key
limit_query_param = 'limit'
# offset(起始位置),從設置的offset值那個位置往後拿limit值的記錄
offset_query_param = 'offset'
# # 設置最大獲取條數
max_limit = 20
# def get_paginated_response(self, data):
# from collections import OrderedDict
# return Response(OrderedDict([('count', self.count), ('data', data)]))
在方法中調用offset分頁
def get(self, request):
# 自定義response result,用於前後端分離
result = {'count': '', 'data': '', 'meta': {'msg': 'OK', 'status': 200}}
try:
# offset分頁
workorder = WorkOrderInfo.objects.all().order_by('id')
count = WorkOrderInfo.objects.count()
pg = MyLimitOffsetPagination()
page_query = pg.paginate_queryset(queryset=workorder, request=request, view=self)
workorder_ser = WorkOrderSerializer(page_query, many=True)
result['data'] = workorder_ser.data
result['count'] = count
except Exception as e:
result['meta']['msg'] = '獲取數據失敗'
result['meta']['status'] = 500
return Response(result)
這裏展示從第5條開始,往後看3條
加密分頁
'''
自定義分頁:加密分頁
加密分頁方式,只能通過點“上一頁”和下一頁訪問數據
'''
class MyCursorPagination(CursorPagination):
cursor_query_param = "cursor"
# 每頁顯示2個數據
page_size = 2
# 排序
ordering = 'id'
page_size_query_param = None
max_page_size = None
在方法中調用加密分頁
加密方法不能按照上兩種常規方法做,需要通過return get_paginated_response 方法來獲取上下頁的加密頁碼,只有通過該頁碼才能訪問對應頁面。這裏因爲暫時用不到就先放下。
def get(self, request):
# 自定義response result,用於前後端分離
result = {'count': '', 'data': '', 'meta': {'msg': 'OK', 'status': 200}}
try:
# 加密分頁
workorder = WorkOrderInfo.objects.all()
# count = WorkOrderInfo.objects.count()
pg = MyCursorPagination()
page_query = pg.paginate_queryset(queryset=workorder, request=request, view=self)
workorder_ser = WorkOrderSerializer(page_query, many=True)
print(workorder_ser)
# res = pg.get_paginated_response(workorder_ser)
# result['data'] = workorder_ser.data
# result['count'] = count
# print(result)
except Exception as e:
result['meta']['msg'] = '獲取數據失敗'
result['meta']['status'] = 500
# 注:使用 get_paginated_response 方法才能返回上下頁的正確頁碼
return pg.get_paginated_response(workorder_ser.data)