rest-framework(2)
一.分页
ps:当数据量比较大时，如何解决分页问题？
解决思路(3种)：
1.记录当前访问页的数据id;(比如访问下一页时，记录当前页的最后一条数据id)
2.最多显示固定页数(比如只显示100页或120页，超过了则不显示)
3.只显示上一页和下一页，并对页码进行加密
分页的实现
1.基于limitoffset
导入
from rest_framework.pagination import LimitOffsetPagination
示例代码
1 urlpatterns = [ 2 url(r'^admin/', admin.site.urls), 3 url(r'^app01/(?P<version>[v1|v2]+)/', include('app01.urls')) 4 ]
1 urlpatterns = [ 2 url(r'^index1/', views.IndexView1.as_view()), 3 url(r'^index2/', views.IndexView2.as_view()), 4 url(r'^index3/', views.IndexView3.as_view()), 5 url(r'^index4/', views.IndexView4.as_view()), 6 url(r'^index5/', views.IndexView5.as_view()), 7 ]
1 from rest_framework.views import APIView 2 from rest_framework.response import Response 3 from app01.serializes.myserializes import MySerializes 4 from rest_framework.pagination import LimitOffsetPagination 5 from app01 import models 6 7 # =========== 可以自己进行自定制分页，基于limitoffset=================== 8 class P1(LimitOffsetPagination): 9 max_limit = 3 # 最大限制默认是None 10 default_limit =2 # 设置每一页显示多少条 11 limit_query_param = 'limit' # 往后取几条 12 offset_query_param = 'offset' # 当前所在的位置 13 14 class IndexView2(APIView): 15 #使用http://127.0.0.1:8080/app01/v1/index2/?offset=2&limit=4可进行判断 16 def get(self,request,*args,**kwargs): 17 user_list = models.UserInfo.objects.all() 18 p1 = P1()#注册分页 19 page_user_list = p1.paginate_queryset(queryset=user_list,request=request,view=self) 20 print('打印的是分页的数据',page_user_list) 21 ser = MySerializes(instance=page_user_list,many=True) #可允许多个 22 # return Response(ser.data) #不含上一页下一页 23 return p1.get_paginated_response(ser.data) 24 25 =======================也可用下面这种形式=========== 26 class BaseResponse(object): 27 def __init__(self,code=1000,data=None,error=None): 28 self.code = code 29 self.data = data 30 self.error = error 31 class IndexView(views.APIView): 32 '''类表示的方式''' 33 def get(self,request,*args,**kwargs): 34 ret = BaseResponse() 35 try: 36 user_list = models.UserInfo.objects.all() 37 p1 = P1() 38 page_user_list = p1.paginate_queryset(queryset=user_list,request=request,view=self) 39 ser = IndexSerializer(instance=page_user_list,many=True) 40 ret.data = ser.data 41 ret.next = p1.get_next_link() 42 except Exception as e: 43 ret.code= 1001 44 ret.error = 'xxxx错误' 45 return Response(ret.__dict__)
2.基于页码的分页
导入
from rest_framework.pagination import PageNumberPagination
1 # ======================基于页码实现的分页============== 2 class P2(PageNumberPagination): 3 #默认每页显示的数据条数 4 page_size = 2 5 #获取url参数中设置的每页显示数据条数 6 page_size_query_param = 'size' 7 #获取url中传入的页码key 8 page_query_param = 'page' 9 #最大支持的每页显示的数据条数 10 max_page_size = 5 11 12 class IndexView3(APIView): 13 #使用http://127.0.0.1:8080/app01/v1/index3/?page=1&page_size=1可进行判断 14 def get(self,request,*args,**kwargs): 15 user_list = models.UserInfo.objects.all() 16 #实例化分页对象，获取数据库中的分页数据 17 p2 = P2() 18 print(p2.page_size_query_description) 19 page_user_list = p2.paginate_queryset(queryset=user_list,request=request,view=self) 20 print('打印的是分页的数据',page_user_list) 21 22 #序列化对象 23 ser = MySerializes(instance=page_user_list,many=True) #可允许多个 24 25 #生成分页和数据 26 # return Response(ser.data) #不含上一页下一页 27 return p2.get_paginated_response(ser.data) 28 29 views.py
3.基于Cursor的分页(页码加密)
1 # =====================基于Cursor的分页============ 2 class P3(CursorPagination): 3 # URL传入的游标参数 4 cursor_query_param = 'cursor' 5 # 默认每页显示的数据条数 6 page_size = 2 7 # URL传入的每页显示条数的参数 8 page_size_query_param = 'size' 9 # 每页显示数据最大条数 10 max_page_size = 3 11 12 # 根据ID从大到小排列 13 ordering = "id" 14 15 class IndexView4(APIView): 16 #使用http://127.0.0.1:8080/app01/v1/index4/?cursor=cj0xJnA9NA%3D%3D&size=3可进行判断 17 def get(self,request,*args,**kwargs): 18 user_list = models.UserInfo.objects.all().order_by('-id') 19 p3 = P3()#注册分页 20 page_user_list = p3.paginate_queryset(queryset=user_list,request=request,view=self) 21 print('打印的是分页的数据',page_user_list) 22 ser = MySerializes(instance=page_user_list,many=True) #可允许多个 23 # return Response(ser.data) #不含上一页下一页 24 return p3.get_paginated_response(ser.data)
二.视图
写视图函数时，用的最多的就是APIview，当然其他的也有必要了解下
先导入
from rest_framework.views import APIView from rest_framework.generics import GenericAPIView from rest_framework.viewsets import GenericViewSet from rest_framework.viewsets import ModelViewSet
1.APIview
1 class IndexView2(APIView): 2 def get(self,request,*args,**kwargs): 3 user_list = models.UserInfo.objects.all() 4 ser = MySerializes(instance=user_list,many=True) 5 return Response(ser.data)
2.GenericAPIview(APIView)
1 from rest_framework.response import Response 2 from rest_framework.generics import GenericAPIView 3 from app01 import models 4 from app01.serializes.myserializes import MySerializes 5 from rest_framework.pagination import LimitOffsetPagination 6 class P1(LimitOffsetPagination): 7 max_limit = 3 # 最大限制默认是None 8 default_limit =2 # 设置每一页显示多少条 9 limit_query_param = 'limit' # 往后取几条 10 offset_query_param = 'offset' # 当前所在的位置 11 12 class IndexView1(GenericAPIView): 13 queryset = models.UserInfo.objects.all() 14 serializer_class = MySerializes 15 pagination_class = P1 16 def get(self,request,*args,**kwargs): 17 user_list = self.get_queryset() 18 p1 = P1() #注册分页 19 data = p1.paginate_queryset(queryset=user_list,request=request,view=self) #获取分页的数据 20 ser = self.get_serializer(instance=data,many=True) #序列化 21 return Response(ser.data) 22 23 GenericAPIView
3.GenericViewSet(ViewSetMixin, generics.GenericAPIView)
1 增 2 POST 3 /users/ 4 删 5 DELETE 6 /users/1/ 7 改 #全部修改 8 PUT 9 /users/1/ 10 #局部修改 11 patch 12 /users/1/ 13 查 14 GET 15 /users/ 16 GET 17 /users/1/ 18 在GET请求的时候如果带ID说明查一条，如果不带则查所有
示例：
1 urlpatterns = [ 2 url(r'^index/$', views.IndexView.as_view()), 3 url(r'^index/(?P<pk>\d+)$', views.IndexView.as_view()), 4 ]
1 class IndexView(views.APIView): 2 3 def get(self,request,*args,**kwargs): 4 pk = kwargs.get('pk') 5 if pk: 6 pass # 获取单条信息 7 else: 8 pass # 获取列表信息 9 10 def post(self,request,*args,**kwargs): 11 pass 12 13 def put(self,request,*args,**kwargs): 14 pass 15 16 def patch(self,request,*args,**kwargs): 17 pass 18 19 def delete(self,request,*args,**kwargs): 20 pass
用GenericViewSet:
1 urlpatterns = [ 2 url(r'^index3/$', views.IndexView3.as_view({'get': 'list','post':'create'})), 3 url(r'^index3/(?P<pk>\d+)/$', views.IndexView3.as_view({'get': 'retrieve'})), 4 ]
1 class IndexView3(GenericViewSet): 2 queryset = models.UserInfo.objects.all() 3 serializer_class = MySerializes 4 pagination_class = P1 5 6 def list(self,request,*args,**kwargs): 7 #获取列表信息 8 return Response('...') 9 10 def retrieve(self,request,*args,**kwargs): 11 #获取单条数据 12 return Response('xxx')
4. ModelViewSet(mixins.CreateModelMixin,mixins.RetrieveModelMixin,mixins.UpdateModelMixin,mixins.DestroyModelMixin,
mixins.ListModelMixin,GenericViewSet)
利用ModelViewSet增删改查不用自己写了，内部把增删改查都干了，当满足不了需求的时候我们也可以自定制
1 urlpatterns = [ 2 3 url(r'^index4/', views.IndexView4.as_view({'get': 'list','post':'create'})), #获取数据和添加数据 4 url(r'^index4\.(?P<format>[a-z0-9]+)/', views.IndexView4.as_view({'get': 'list','post':'create'})), #.json想让页面上显示成json格式 5 url(r'^index4/(?P<pk>\d+)/', views.IndexView4.as_view({'get': 'retrieve', 'delete': 'destroy','put':'partial_update'})), #查看单条，删除，修改数据 6 url(r'^index4(?P<pk>\d+)\.(?P<format>[a-z0-9]+)/', views.IndexView4.as_view({'get': 'retrieve', 'delete': 'destroy','put':'partial_update'})), 7 8 ] 9 10 urls.py
1 注意啦：用ModelSerializer这种方法必须要用IndexSerializer(ModelSerializer)这种方式序列化 2 class P2(PageNumberPagination): 3 page_size = 3 #每一页显示的条数 4 page_query_param = 'page' #获取参数中传入的页码 5 page_size_query_param = 'size' #获取url参数中每页显示的数据条数 6 7 max_page_size = 5 8 9 class IndexSerializer(ModelSerializer): 10 class Meta: 11 model = models.UserInfo 12 fields = "__all__" 13 14 class IndexView4(ModelViewSet): 15 queryset = models.UserInfo.objects.all() 16 serializer_class = IndexSerializer 17 pagination_class = P2
自定制
1 class P2(PageNumberPagination): 2 page_size = 3 #每一页显示的条数 3 page_query_param = 'page' #获取参数中传入的页码 4 page_size_query_param = 'size' #获取url参数中每页显示的数据条数 5 6 max_page_size = 5 7 8 class IndexSerializer(ModelSerializer): 9 class Meta: 10 model = models.UserInfo 11 fields = "__all__" 12 13 class IndexView4(ModelViewSet): 14 queryset = models.UserInfo.objects.all() 15 serializer_class = IndexSerializer 16 pagination_class = P2 17 18 def list(self, request, *args, **kwargs): 19 '''获取get请求的所有''' 20 pass 21 22 def retrieve(self, request, *args, **kwargs): 23 '''查看单条数据''' 24 pass 25 def destroy(self, request, *args, **kwargs): 26 '''删除DELETE''' 27 pass 28 def create(self, request, *args, **kwargs): 29 '''添加数据POST''' 30 pass 31 def update(self, request, *args, **kwargs): 32 '''全部修改PUT''' 33 pass 34 def partial_update(self, request, *args, **kwargs): 35 '''局部修改PATCH''' 36 pass 37 38 基于ModelViewSet自定制
三.路由
1.自定义路由
1 # http://127.0.0.1:8000/api/v1/auth/ 2 url(r'^auth/$', views.AuthView.as_view()), 3 # http://127.0.0.1:8000/api/v1/auth.json # 想要让页面显示json格式 4 url(r'^auth\.(?P<format>[a-z0-9]+)$', views.AuthView.as_view()), 5 # http://127.0.0.1:8000/api/v1/auth/1/ 6 url(r'^auth/(?P<pk>\d+)/$', views.AuthView.as_view()), 7 # http://127.0.0.1:8000/api/v1/auth/1.json 8 url(r'^auth/(?P<pk>\d+)\.(?P<format>[a-z0-9]+)$', views.AuthView.as_view()), 9 class AuthView(views.APIView): 10 11 def get(self,request,*args,**kwargs): 12 return Response('...')
2.半自动路由
1 url(r'^index/$', views.IndexView.as_view({'get':'list','post':'create'})), 2 url(r'^index\.(?P<format>[a-z0-9]+)$', views.IndexView.as_view({'get':'list','post':'create'})), 3 url(r'^index/(?P<pk>\d+)/$', views.IndexView.as_view({'get':'retrieve','delete':'destroy','put':'update','patch':'partial_update'})), 4 url(r'^index(?P<pk>\d+)\.(?P<format>[a-z0-9]+)$', views.IndexView.as_view({'get':'retrieve','delete':'destroy','put':'update','patch':'partial_update'})), 5 6 class IndexView(viewsets.ModelViewSet): 7 queryset = models.UserInfo.objects.all() 8 serializer_class = IndexSerializer 9 pagination_class = P2
3.全自动路由，会自动生成四个url
1 router = DefaultRouter() 2 router.register('index',views.IndexViewSet) 3 urlpatterns = [ 4 url(r'^', include(router.urls)), 5 ] 6 7 class IndexViewSet(viewsets.ModelViewSet): 8 queryset = models.UserInfo.objects.all() 9 serializer_class = IndexSerializer 10 pagination_class = P2 11 12 class IndexSerializer(serializers.ModelSerializer): 13 class Meta: 14 model = models.UserInfo 15 fields = "__all__"
四.渲染器
根据 用户请求URL 或 用户可接受的类型，筛选出合适的 渲染组件。
用户请求URL：
- http://127.0.0.1:8000/test/?format=json
- http://127.0.0.1:8000/test.json
用户请求头：
Accept:text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
1.Json
访问URL
http://127.0.0.1:8000/test/?format=json
http://127.0.0.1:8000/test.json
http://127.0.0.1:8000/test/
Urls.py
1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 from rest_framework.views import APIView 4 from rest_framework.response import Response 5 from rest_framework import serializers 6 7 from rest_framework.renderers import JSONRenderer 8 9 from .. import models 10 11 12 class TestSerializer(serializers.ModelSerializer): 13 class Meta: 14 model = models.UserInfo 15 fields = "__all__" 16 17 18 class TestView(APIView): 19 renderer_classes = [JSONRenderer, ] 20 21 def get(self, request, *args, **kwargs): 22 user_list = models.UserInfo.objects.all() 23 ser = TestSerializer(instance=user_list, many=True) 24 return Response(ser.data)
2.表格
访问URL：
http://127.0.0.1:8000/test/?format=admin
http://127.0.0.1:8000/test.admin
http://127.0.0.1:8000/test/
1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 from rest_framework.views import APIView 4 from rest_framework.response import Response 5 from rest_framework import serializers 6 7 from rest_framework.renderers import AdminRenderer 8 9 from .. import models 10 11 12 class TestSerializer(serializers.ModelSerializer): 13 class Meta: 14 model = models.UserInfo 15 fields = "__all__" 16 17 18 class TestView(APIView): 19 renderer_classes = [AdminRenderer, ] 20 21 def get(self, request, *args, **kwargs): 22 user_list = models.UserInfo.objects.all() 23 ser = TestSerializer(instance=user_list, many=True) 24 return Response(ser.data)
3.From表单
访问URL：
http://127.0.0.1:8000/test/?format=form
http://127.0.0.1:8000/test.form
http://127.0.0.1:8000/test/
1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 from rest_framework.views import APIView 4 from rest_framework.response import Response 5 from rest_framework import serializers 6 7 from rest_framework.renderers import JSONRenderer 8 from rest_framework.renderers import AdminRenderer 9 from rest_framework.renderers import HTMLFormRenderer 10 11 from .. import models 12 13 class TestSerializer(serializers.ModelSerializer): 14 class Meta: 15 model = models.UserInfo 16 fields = "__all__" 17 18 19 class TestView(APIView): 20 renderer_classes = [HTMLFormRenderer, ] 21 22 def get(self, request, *args, **kwargs): 23 user_list = models.UserInfo.objects.all().first() 24 ser = TestSerializer(instance=user_list, many=False) 25 return Response(ser.data)
4.自定义模版
访问URL：
http://127.0.0.1:8000/test/?format=html
http://127.0.0.1:8000/test.html
http://127.0.0.1:8000/test/
1 from django.conf.urls import url, include 2 from web.views import s11_render 3 4 urlpatterns = [ 5 url(r'^test/$', s11_render.TestView.as_view()), 6 url(r'^test\.(?P<format>[a-z0-9]+)', s11_render.TestView.as_view()), 7 ]
1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 from rest_framework.views import APIView 4 from rest_framework.response import Response 5 from rest_framework import serializers 6 from rest_framework.renderers import TemplateHTMLRenderer 7 8 from .. import models 9 10 class TestSerializer(serializers.ModelSerializer): 11 class Meta: 12 model = models.UserInfo 13 fields = "__all__" 14 15 class TestView(APIView): 16 renderer_classes = [TemplateHTMLRenderer, ] 17 18 def get(self, request, *args, **kwargs): 19 user_list = models.UserInfo.objects.all().first() 20 ser = TestSerializer(instance=user_list, many=False) 21 return Response(ser.data, template_name='user_detail.html')
1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Title</title> 6 </head> 7 <body> 8 {{ user }} 9 {{ pwd }} 10 {{ ut }} 11 </body> 12 </html>
5.浏览器模式API+Json
访问URL：
http://127.0.0.1:8000/test/?format=api
http://127.0.0.1:8000/test.api
http://127.0.0.1:8000/test/
1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 from rest_framework.views import APIView 4 from rest_framework.response import Response 5 from rest_framework import serializers 6 7 from rest_framework.renderers import JSONRenderer 8 from rest_framework.renderers import BrowsableAPIRenderer 9 10 from .. import models 11 12 class TestSerializer(serializers.ModelSerializer): 13 class Meta: 14 model = models.UserInfo 15 fields = "__all__" 16 17 18 class CustomBrowsableAPIRenderer(BrowsableAPIRenderer): 19 def get_default_renderer(self, view): 20 return JSONRenderer() 21 22 23 class TestView(APIView): 24 renderer_classes = [CustomBrowsableAPIRenderer, ] 25 26 def get(self, request, *args, **kwargs): 27 user_list = models.UserInfo.objects.all().first() 28 ser = TestSerializer(instance=user_list, many=False) 29 return Response(ser.data, template_name='user_detail.html')
注意：如果同时多个存在时，自动根据URL后缀来选择渲染器。
