drf 视图类 GenericAPIView 及扩展

1、2个视图基类

原来五个接口 继承APIview

**现在继承GenericAPIView **

1.1、GenericAPIView：属性和方法

属性

queryset
要序列化的属性

serializer_class
序列化类

一下作为了解
lookup_field
通过get_obj 获取单个对象的查询key值，value值是路由中传递来的

filter_backends
过滤类

pagination_class
分页类

方法
get_queryset
获取要序列化的数据

get_object
根据lookup_field配置是的参数获取单个对象

get_serializer
获取序列化类，咱们直接用的

get_serializer_class
获取序列化类，不是咱们直接用的get_serializer调用了它

以下了解
filter_queryset
跟过滤有关系

paginate_xxxx
跟分页有关

1.2、基于APIView 写5个接口

class UserView(APIView):def get(self, request):res_list = User.objects.all()ser = UserSerializer(instance=res_list, many=True)return Response(ser.data)def post(self, request):ser = UserSerializer(data=request.data)if ser.is_valid():ser.save()return Response({'code': 100, 'msg': "新增成功"}, status=201)else:return Response({'code': 101, 'msg': ser.errors})class UserDetailView(APIView):def get(self, request, pk):obj = User.objects.filter(pk=pk).first()ser = UserSerializer(instance=obj)return Response(ser.data)def put(self, request, pk):obj = User.objects.filter(pk=pk).first()ser = UserSerializer(instance=obj, data=request.data)if ser.is_valid():ser.save()return Response({'code': 100, 'msg': "修改成功"}, status=201)else:return Response({'code': 101, 'msg': ser.errors})def delete(self, request, pk):User.objects.filter(pk=pk).delete()return Response('')

1.3、基于GenericAPIView写5个接口

class UserView(GenericAPIView):# 配置两个 类属性queryset = User.objects.all()serializer_class = UserSerializerdef get(self, request):res_list = self.get_queryset()  # 提高扩展性ser = self.get_serializer(instance=res_list, many=True)return Response(ser.data)def post(self, request):ser = self.get_serializer(data=request.data)if ser.is_valid():ser.save()return Response({'code': 100, 'msg': "新增成功"}, status=201)else:return Response({'code': 101, 'msg': ser.errors})class UserDetailView(GenericAPIView):queryset = User.objects.all()serializer_class = UserSerializerdef get(self, request, pk):# obj = self.get_queryset().filter(pk=pk).first()# queryset.get({'pk':'有名分组分出来的'}obj = self.get_object()  # 根据传入的pk，获取一条数据ser = self.get_serializer(instance=obj)return Response(ser.data)def put(self, request, pk):obj = self.get_object()ser = self.get_serializer(instance=obj, data=request.data)if ser.is_valid():ser.save()return Response({'code': 100, 'msg': "修改成功"}, status=201)else:return Response({'code': 101, 'msg': ser.errors})def delete(self, request, pk):self.get_queryset().filter(pk=pk).delete()return Response('')

2、5个视图扩展类

2.1 基于GenericAPIView+5个视图扩展类写接口

必须配合GenericAPIVi 使用，不能配合APIView使用

from rest_framework.mixins import RetrieveModelMixin, CreateModelMixin, UpdateModelMixin, DestroyModelMixin

CreateModelMixin:写了一个create方法，就是原来咱们post中的代码

ListModelMixin: 写了一个list方法，就是原来咱们的get 获取单个

UpdateModelMixin: 写了一个update方法，就是咱们原来的put

RetrieveModelMixin: 写了一个retrieve方法，就是原来咱们的get

DestroyModelMixin: 写了一个destroy方法，就是原来咱们的delete

from rest_framework.generics import GenericAPIView
from rest_framework.mixins import RetrieveModelMixin, CreateModelMixin, UpdateModelMixin, DestroyModelMixin,ListModelMixinclass Books(ListModelMixin, GenericAPIView, CreateModelMixin):queryset = Book.objects.all()serializer_class = BookSerdef get(self, request, *args, **kwargs):return self.list(request, *args, **kwargs)def post(self, request, *args, **kwargs):return self.create(request, *args, **kwargs)class BookDetail(RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin, GenericAPIView):queryset = Book.objects.all()serializer_class = BookSerdef get(self, request, *args, **kwargs):return self.retrieve(request, *args, **kwargs)def put(self, request, *args, **kwargs):return self.update(request, *args, **kwargs)def delete(self, request, *args, **kwargs):return self.destroy(request, *args, **kwargs)

3、九个视图子类

视图类：继承GenericaAPIView+ 某个或某几个视图扩展类

from rest_framework.generics import ListAPIView, CreateAPIView, RetrieveAPIView, UpdateAPIView, DestroyAPIView
from rest_framework.generics import ListCreateAPIView, RetrieveUpdateDestroyAPIView, RetrieveDestroyAPIView, \RetrieveUpdateAPIView

3.1、基于九个视图子类写接口

class BookView(ListCreateAPIView):queryset = Book.objects.all()serializer_class = BookSerdef get(self, request, *args, **kwargs):return self.list(request, *args, **kwargs)def post(self, request, *args, **kwargs):return self.create(request, *args, **kwargs)class BookViewDetail(RetrieveUpdateAPIView):queryset = Book.objects.all()serializer_class = BookSerdef get(self, request, *args, **kwargs):return self.retrieve(request, *args, **kwargs)def put(self, request, *args, **kwargs):return self.update(request, *args, **kwargs)class BookDelete(RetrieveUpdateDestroyAPIView):queryset = Book.objects.all()serializer_class = BookSerdef get(self, request, *args, **kwargs):return self.retrieve(request, *args, *kwargs)def put(self, request, *args, **kwargs):return self.update(request, *args, **kwargs)def delete(self, request, *args, **kwargs):return self.destroy(request,* args, **kwargs)

4、视图集

4.1、继承ModelviewSet 写五个接口

from rest_framework,viewsets import ModelviewSet,ReadOnlyModelViewSet  #只读
class BookViews(ModelViewSet):queryset = Book.objects.all()serializer_class = BookSer# 路由
path('book/',views.BookViews.as_view({'get': 'list','post':'create'})),path('book/<int:pk>/',views.BookViews.as_view({'get': 'retrieve','put':'update','delete':'destroy'})),

4.2、源码分析ViewSetMixin

@classonlymethod
def as_view(cls, actions=None, **initkwargs):# 路由中as_view中必须传参数，必须传字典：{'get': 'list', 'post': 'create'}if not actions: raise TypeError("The `actions` argument must be provided when ""calling `.as_view()` on a ViewSet. For example ""`.as_view({'get': 'list'})`")# 路由匹配成功，执行view(request)，request是老的requestdef view(request, *args, **kwargs):# actions={'get': 'list', 'post': 'create'}for method, action in actions.items():# method:get      action:list# self 是视图类的对象中通过反射，查找list，# handler视图类中的list方法handler = getattr(self, action)# 向视图类的对象中，反射 method:get,handler:list方法# self.get=listsetattr(self, method, handler)return self.dispatch(request, *args, **kwargs)return csrf_exempt(view)# 只要继承了ViewSetMixin，以后路由写法变量，都要写成：views.UserView.as_view({'get': 'list', 'post': 'create'}))
# 这样写好以后，对应的请求方式来了，就会执行配置的方法# 扩展：-以后只要继承了ViewSetMixin，视图类中可以写任意名字的方法，不用非得写get，post，delete

4.3、总结

APIView：as_view,dispatch
GenericAPIView:继承了APIView
类属性
方法

5、五个视图扩展类：
ListModelMixin
CreateModelMixin
RetrieveModelMixin
UpdateModelMixin
DestroyModelMixin
每个类里面有一个方法

9个视图子类：
5个视图扩展类+GenericAPIView组合

视图集
ViewSetMixin:魔法 重写了as_view，只要继承它，路由写法就变了
ViewSet: ViewSetMixin+APIView
GenericViewSet： ViewSetMixin+GenericAPIView
ModelViewSet: 5个视图扩展类+GenericViewSet
ReadOnlyModelViewSet： 2个视图扩展类+GenericViewSet
[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-gCw2EJXi-1665059450643)(C:\Users\82576\Downloads\视图类继承关系.png)]

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