9.drf-视图

在视图中，如果参数有request，我们可以直接使用，如果参数没有，则可以通过self.request获取

 1.APIView

我们之前使用的基本上都是APIView,给我们提供了免除csrf验证，请求封装，版本控制，认证，权限和限流的功能，以下是源码展示

 

 

 

2.GenericAPIView

GenericAPIView 继承了APIView,增加了一些功能，如get_queryset,get_object等，实际开发中我们不会直接继承该类，该类是为后续的高度封装做的准备

 

 

 

3.GenericViewSet

开发中一般也很少直接去继承他，因为他也属于是 中间人类，在原来 GenericAPIView 基础上又增加了一个映射而已

 

 

 

 

 

 

GenericViewSet类中没有定义任何代码，他就是继承 ViewSetMixin 和 GenericAPIView，也就说他的功能就是将继承的两个类的功能继承到一起。

• GenericAPIView，将数据库查询、序列化类的定义提取到类变量中，便于后期处理。

• ViewSetMixin，将 get/post/put/delete 等方法映射到 list、create、retrieve、update、partial_update、destroy方法中，让视图不再需要两个类。

# urls.py

from django.urls import path, re_path, include
from app01 import views

urlpatterns = [
    path('api/users/', views.UserView.as_view({"get":"list","post":"create"})),
    path('api/users/<int:pk>/', views.UserView.as_view({"get":"retrieve","put":"update","patch":"partial_update","delete":"destory"})),
]

# views.py

from rest_framework.viewsets import GenericViewSet
from rest_framework.response import Response

    
class UserView(GenericViewSet):
    
    # 认证、权限、限流等
    queryset = models.UserInfo.objects.filter(status=True)
    serializer_class = 序列化类
    
    def list(self, request):
        # 业务逻辑：查看列表
        queryset = self.get_queryset()
        ser = self.get_serializer(intance=queryset,many=True)
        print(ser.data)
        return Response({"code": 0, 'data': "..."})

    def create(self, request):
        # 业务逻辑：新建
        return Response({'code': 0, 'data': "..."})
    
    def retrieve(self, request,pk):
        # 业务逻辑：查看某个数据的详细
        return Response({"code": 0, 'data': "..."})

    def update(self, request,pk):
        # 业务逻辑：全部修改
        return Response({'code': 0, 'data': "..."})
    
    def partial_update(self, request,pk):
        # 业务逻辑：局部修改
        return Response({'code': 0, 'data': "..."})
    
    def destory(self, request,pk):
        # 业务逻辑：删除
        return Response({'code': 0, 'data': "..."})

 

4.五大视图类

助我们封装了增删改查查常用的的5个接口，结合着GenericViewSet使用

4.1 ListModelMixin

查看数据列表

 

 

 

路由

from django.urls import path
from app01 import views

urlpatterns = [
    path('api/user/', views.User.as_view({'get': 'list'})),
]

视图

from app01.models import UserInfo
from rest_framework import serializers
from rest_framework.viewsets import GenericViewSet
from rest_framework.mixins import ListModelMixin, \
    RetrieveModelMixin, \
    CreateModelMixin, \
    UpdateModelMixin, \
    DestroyModelMixin


class UserModelSerializer(serializers.ModelSerializer):
    class Meta:
        model = UserInfo
        fields = ['username', 'age', 'email']


class User(ListModelMixin, GenericViewSet):
    queryset = UserInfo.objects.all()
    serializer_class = UserModelSerializer

 

4.2 RetrieveModelMixin

查看指定数据

 

 

 路由

urlpatterns = [
    path('api/user/<int:pk>/', views.User.as_view({'get': 'retrieve'})),
]

视图

from app01.models import UserInfo
from rest_framework import serializers
from rest_framework.viewsets import GenericViewSet
from rest_framework.mixins import ListModelMixin, \
    RetrieveModelMixin, \
    CreateModelMixin, \
    UpdateModelMixin, \
    DestroyModelMixin


class UserModelSerializer(serializers.ModelSerializer):
    class Meta:
        model = UserInfo
        fields = ['username', 'age', 'email']


class User(ListModelMixin, RetrieveModelMixin, GenericViewSet):
    queryset = UserInfo.objects.all()
    serializer_class = UserModelSerializer

 

4.3 CreateModelMixin

创建数据

我们在保存数据到数据库中，可能前端传过来的数据只是部分，我们还需要对其他字段进行指定，可以重写perform_create

 

 

 路由

urlpatterns = [
    path('api/user/', views.User.as_view({'get': 'list', 'post': 'create'})),
]

视图

from app01.models import UserInfo
from rest_framework import serializers
from rest_framework.viewsets import GenericViewSet
from rest_framework.mixins import ListModelMixin, \
    RetrieveModelMixin, \
    CreateModelMixin, \
    UpdateModelMixin, \
    DestroyModelMixin


class UserModelSerializer(serializers.ModelSerializer):
    class Meta:
        model = UserInfo
        fields = ['username', 'age', 'email']


class User(ListModelMixin, RetrieveModelMixin, CreateModelMixin, GenericViewSet):
    queryset = UserInfo.objects.all()
    serializer_class = UserModelSerializer

    def perform_create(self, serializer):
        serializer.save(password="123")

 

4.4 DestroyModelMixin

删除数据

 

 

 路由

urlpatterns = [
    path('api/user/<int:pk>/', views.User.as_view({'get': 'retrieve', 'delete': 'destroy'})),
]

视图

from app01.models import UserInfo
from rest_framework import serializers
from rest_framework.viewsets import GenericViewSet
from rest_framework.mixins import ListModelMixin, \
    RetrieveModelMixin, \
    CreateModelMixin, \
    UpdateModelMixin, \
    DestroyModelMixin


class UserModelSerializer(serializers.ModelSerializer):
    class Meta:
        model = UserInfo
        fields = ['username', 'age', 'email']


class User(ListModelMixin, RetrieveModelMixin, CreateModelMixin, DestroyModelMixin, GenericViewSet):
    queryset = UserInfo.objects.all()
    serializer_class = UserModelSerializer

 

4.5 UpdateModelMixin

• 全部更新：对于序列化起中fields中非只读的字段必须都传递过来，进行更新

• 局部更新：对于序列化中的fields中非只读的字段可以传递过来部分进行更新

 

 

 

路由

from django.urls import path
from app01 import views

urlpatterns = [
    path('api/user/', views.User.as_view({'get': 'list', 'post': 'create'})),
    path('api/user/<int:pk>/', views.User.as_view(
        {'get': 'retrieve',
         'delete': 'destroy',
         'put': 'update',
         'patch': 'partial_update'
         }
    )
         ),
]

视图

from app01.models import UserInfo
from rest_framework import serializers
from rest_framework.viewsets import GenericViewSet
from rest_framework.mixins import ListModelMixin, \
    RetrieveModelMixin, \
    CreateModelMixin, \
    UpdateModelMixin, \
    DestroyModelMixin


class UserModelSerializer(serializers.ModelSerializer):
    class Meta:
        model = UserInfo
        fields = ['username', 'age', 'email']


class User(ListModelMixin, RetrieveModelMixin, CreateModelMixin, DestroyModelMixin, UpdateModelMixin, GenericViewSet):
    queryset = UserInfo.objects.all()
    serializer_class = UserModelSerializer

 

小结：

• 接口与数据库操作无关，直接继承APIView

• 接口背后需要对数据库进行操作，一般：ModelViewSet 或 CreateModelMixin、ListModelMixin...

• 利用钩子自定义功能。重写某个写方法，实现更加完善的功能。