DRF的视图组件

DRF的视图组件

DRF的视图组件大概分以下几类

两大视图类

APIView、GenericAPIView

from rest_framework.views import APIView

from rest_framework.generics import GenericAPIView

	'''

	APIView继承Django的View

	   1) View：将请求方式与视图类的同名方法建立映射，完成请求响应

	   2) APView：除了拥有View的功能之外,还有一些独有的功能

			View的功能；

	   		重写as_view禁用csrf认证；

	   		重写dispatch：请求、响应、渲染、异常、解析、三大认证

	   		多了一堆类属性，可以完成视图类的局部配置

	'''

# GenericAPIView提供了三个方法：get_object()、get_queryset()、get_serializer()

from rest_framework.generics import GenericAPIView

class StudentGenericAPIView(GenericAPIView):

    queryset = models.Student.objects.all()		# 取到所有的学生对象,取到的是一个queryset对象,其实用这些工具我们至少都要定义一个queryset和一个serializer_class

    serializer_class = serializers.StudentModelSerializer		# 

    def get(self, request, *args, **kwargs):

        stu_query = self.get_queryset()

        stu_ser = self.get_serializer(stu_query, many=True)

        return Response(stu_ser.data)

六大视图工具类

RetrieveModelMixin, ListModelMixin, CreateModelMixin, UpdateModelMixin, DestroyModelMixin五大工具类
六大工具方法:retrieve、list、create、update、partial_update、destroy
```
  from rest_framework import mixins 
```

class StudentMixinGenericAPIView(mixins.ListModelMixin, mixins.CreateModelMixin, GenericAPIView):

queryset = models.Student.objects.all()

serializer_class = serializers.StudentModelSerializer

    def get(self, request, *args, **kwargs):

        return self.list(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):

        return self.create(request, *args, **kwargs)

```

九大工具视图类

CreateAPIView, DestroyAPIView, ListAPIView, ListCreateAPIView, RetrieveAPIView, RetrieveDestroyAPIView, RetrieveUpdateAPIView, RetrieveUpdateDestroyAPIView, UpdateAPIView

  from rest_framework.generics import CreateAPIView, RetrieveAPIView, ListAPIView, UpdateAPIView, DestroyAPIView

  class StudentMixinAPIView(CreateAPIView, RetrieveAPIView, ListAPIView, UpdateAPIView, DestroyAPIView):

      queryset = models.Student.objects.all()

      serializer_class = serializers.StudentModelSerializer

      # url中单查，不一定必须提供主键，下面的定义就是提供一个供查询的唯一键的字段名即可,当然,需要时表中有的字段,或者是外键字段

      lookup_url_kwarg = 'id'

      # 有删除需求的接口继承DestroyAPIView，重写destroy完成字段删除,但其实这个方法没有太大必要,因为这种删除需求会彻底在库中删除数据,而在生产中我们一般只会给is_delet字段修改值而已,所以不需要这个方法,重写的时候只需要修改is_delete字段就好

      def destroy(self, request, *args, **kwargs):

          pass

两大视图集基类

ViewSet, GenerivViewSet

  from rest_framework.viewsets import ModelViewSet

  # 实际上ModelViewSet的源码里面是这么定义的,就是直接继承的mixins(视图工具类)里面的各种方法,几乎包含了所有的方法,除此之外还有一个仅用只读的Model视图集,名为ReadOnlyModelViewSet,

class ModelViewSet(mixins.CreateModelMixin,

mixins.RetrieveModelMixin,

mixins.UpdateModelMixin,

mixins.DestroyModelMixin,

mixins.ListModelMixin,

GenericViewSet):

pass

# 该类只继承了单查和群查,所以

class ReadOnlyModelViewSet(mixins.RetrieveModelMixin,

mixins.ListModelMixin,

GenericViewSet):

pass

# 而两大大视图集基类均是继承自ViewSetMixin

class GenericViewSet(ViewSetMixin, generics.GenericAPIView):

    '''

    可以自定义映射关系的GenericAPIView

    '''

	pass

class ViewSet(ViewSetMixin, views.APIView):

    '''

    可以自定义映射关系的APIView

    '''

	pass

'''

ViewSetMixin所完成的主要功能就是重写as_view()和view(),从而在url里面可以这样写映射关系,比如

as_view({

	'get':'my_get',

	'post':'my_post',

	})

	这样映射关系写过之后,前端发来的url的类型get和post就会映射到视图层的my_get和my_post,这两个方法都是写在View.py的响应方法里面

'''

```