rest-framework视图

一、关于视图的认识

• 1、django中使用类来写视图的时候我们都要继承一个View的类
• 2、前面我们使用rest-framework的时候都要继承一个APIView的类

二、关于GenericAPIView的使用

• 1、定义url

  from django.urls import path
  
  from . views import role, user, group
  
  urlpatterns = [
      ...
      path('role4/', role.RoleView4.as_view())
  ]
  

• 2、定义视图类

  from rest_framework.generics import GenericAPIView
  
  class RoleView4(GenericAPIView):
      # 获取全部的数据
      queryset = models.RoleModel.objects.all()
      # 序列化的类
      serializer_class = RoleSerializer3
      # 分页的类
      pagination_class = MyPageNumberPagination
  
      def get(self, request, *args, **kwargs):
          roles = self.get_queryset()
          pager_roles = self.paginate_queryset(roles)
          ser = self.get_serializer(instance=pager_roles, many=True)
          return Response(ser.data)
  

• 3、总结

  • 1.这个类继承了APIview
  • 2.不太好用,先定义了类还要定义get的方法

三、关于GenericViewSet的使用

• 1、定义视图类

  from rest_framework.viewsets import GenericViewSet
  
  class RoleView5(GenericViewSet):
      # 获取全部的数据
      queryset = models.RoleModel.objects.all()
      # 序列化的类
      serializer_class = RoleSerializer3
      # 分页的类
      pagination_class = MyPageNumberPagination
  
      def list(self, request, *args, **kwargs):
          roles = self.get_queryset()
          pager_roles = self.paginate_queryset(roles)
          ser = self.get_serializer(instance=pager_roles, many=True)
          return Response(ser.data)
  

• 2、定义url

  urlpatterns = [
      ...
      path('role5/', role.RoleView5.as_view({'get': 'list', }))
  ]
  

• 3、总结

  • 1.GenericViewSet类继承了ViewSetMixin, generics.GenericAPIView,
  • 2.其中ViewSetMixin类就是重写了as_view()方法就是
  • 3.这个视图也不太好用

四、使用ListModelMixin和GenericViewSet类

• 1、视图类

  from rest_framework.mixins import ListModelMixin
  
  class RoleView6(ListModelMixin, GenericViewSet):
      queryset = models.RoleModel.objects.all()
      serializer_class = RoleSerializer3
      pagination_class = MyPageNumberPagination
  

• 2、定义url

  urlpatterns = [
      ...
      path('role6/', role.RoleView6.as_view({'get': 'list', }))
  ]
  

• 3、关于ListModelMixin的源码(会帮我们实现上面写的GenericViewSet中代码)

  class ListModelMixin(object):
      """
      List a queryset.
      """
      def list(self, request, *args, **kwargs):
          queryset = self.filter_queryset(self.get_queryset())
  
          page = self.paginate_queryset(queryset)
          if page is not None:
              serializer = self.get_serializer(page, many=True)
              return self.get_paginated_response(serializer.data)
  
          serializer = self.get_serializer(queryset, many=True)
          return Response(serializer.data)
  

五、关于使用CreateModelMixin创建数据

• 1、视图类

  from rest_framework.mixins import ListModelMixin, CreateModelMixin
  
  class RoleView6(ListModelMixin, CreateModelMixin, GenericViewSet):
      queryset = models.RoleModel.objects.all()
      serializer_class = RoleSerializer3
      pagination_class = MyPageNumberPagination
  

• 2、关于url配置

  urlpatterns = [
      path('role6/', role.RoleView6.as_view({'get': 'list', 'post': 'create'}))
  ]
  

六、终极版直接继承ModelViewSet

• 1、ModelViewSet类源码(什么都没做,只是多继承了几个)

  class ModelViewSet(mixins.CreateModelMixin,
                    mixins.RetrieveModelMixin,
                    mixins.UpdateModelMixin,
                    mixins.DestroyModelMixin,
                    mixins.ListModelMixin,
                    GenericViewSet):
      """
      A viewset that provides default `create()`, `retrieve()`, `update()`,
      `partial_update()`, `destroy()` and `list()` actions.
      """
      pass
  

• 2、关于上面继承几个类的使用

  • 1.CreateModelMixin创建数据/新增数据
  • 2.RetrieveModelMixin获取单条数据
  • 3.UpdateModelMixin更新数据(分全部与局部更新)
  • 4.DestroyModelMixin删除数据
  • 5.ListModelMixin获取列表数据

• 3、视图类的代码

  from rest_framework.viewsets import ModelViewSet
  
  class RoleView6(ModelViewSet):
      queryset = models.RoleModel.objects.all()
      serializer_class = RoleSerializer3
      pagination_class = MyPageNumberPagination
  

• 4、重点是配置url

  可以查看源码进行配置

  urlpatterns = [
      ...
      path('role5/', role.RoleView5.as_view({'get': 'list', })),
      path('role6/', role.RoleView6.as_view({'get': 'list', 'post': 'create'})),
      path('role6/<int:pk>/', role.RoleView6.as_view({'get': 'retrieve', 'delete': 'destroy', 'put': 'update', 'patch': 'partial_update'})),
  ]
  

• 5、关于put和patch的认识

  • 1.put是全局更新
  • 2.patch是局部更新

七、总结:关于使用哪个视图类来继承的问题

• 1、如果涉及到增删改查就直接使用ModelViewSet

  from rest_framework.viewsets import ModelViewSet
  
  class GoodView(ModelViewSet):
    pass
  

• 2、如果是增删就可以单独继承CreateModelMixin、DestroyModelMixin、GenericViewSet

  from rest_framework.viewsets import GenericViewSet
  from rest_framework.mixins import CreateModelMixin, DestroyModelMixin
  
  class GoodView(CreateModelMixin, DestroyModelMixin, GenericViewSet):
    pass
  

• 3、如果业务逻辑比较复杂还是建议使用APIView或者GenericViewSet

• 4、注意要合理的配置路由

八、重点:路由的注册

使用场景:上面介绍的,使用了混入及genericViewSet的时候需要特别配置url,配置步骤如下:

• 1、定义好serializer

  from rest_framework import serializers
  from goods import models
  
  class GoodsSerializer(serializers.ModelSerializer):
      """
      序列化商品
      """
  
      class Meta(object):
          model = models.GoodsModel
          fields = '__all__'
  

• 2、视图类

  from rest_framework.viewsets import GenericViewSet, ModelViewSet
  from rest_framework.mixins import ListModelMixin
  from goods import serializers
  from goods import models
  
  class GoodView(ListModelMixin, GenericViewSet):
      """
      配置产品的视图类
      """
  
      queryset = models.GoodsModel.objects.all()
      serializer_class = serializers.GoodsSerializer
  

• 3、路由的注册

  from django.urls import path, include, re_path
  from rest_framework.routers import DefaultRouter
  from goods.views.goods import GoodView
  
  router = DefaultRouter()
  router.register('goods', GoodView, base_name='goods')
  router.register('category', goods.GoodsCategoryView, base_name='category')
  ...
  
  urlpatterns = [
      path('', include(router.urls)),
  ]