day03---继承5大扩展类和五大子类

绝地灬酷狼 2022-12-09 14:56 115阅读 0赞

## 一:继承五大扩展类： ##

1：序列化返回多个模型类对象：（ListModelMixin）  
1.1:ListModelMixin干了什么？？  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzQxNzU3_size_16_color_FFFFFF_t_70_pic_center]  
1.2：所以继承之后的代码是：

class BooksView(GenericAPIView, ListModelMixin):
    
        # 定义类属性
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
    
        # :序列化返回多个模型类对象
        def get(self, request):
            return self.list(request)

2：序列化新建单一资源：（CreateModelMixin）  
2.1:CreateModelMixin做了啥？  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzQxNzU3_size_16_color_FFFFFF_t_70_pic_center 1]  
2.2：继承后的代码：

class BooksView(GenericAPIView, ListModelMixin, CreateModelMixin):
    
        # 定义类属性
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
    
        # :序列化返回多个模型类对象
        def get(self, request):
            return self.list(request)
    
        # 反序列化新建单一资源
        def post(self, request):
           return self.create(request)

3：反序列化单一资源：（RetriveModelMixin）  
3.1:RetriveModelMixin做了什么？  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzQxNzU3_size_16_color_FFFFFF_t_70_pic_center 2]  
3.2：继承后的代码：

class BookView(GenericAPIView, RetrieveModelMixin):
    
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
        lookup_field = "pk"
        lookup_url_kwarg = "pk"
    
        # 1：序列化返回单一资源
        def get(self, request, pk):
            return self.retrieve(request, pk)

4：反序列化更新：（UpdateModelMixin）  
4.1：UpdateModelMixin做了什么？  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzQxNzU3_size_16_color_FFFFFF_t_70_pic_center 3]  
4.2：继承之后的代码：

class BookView(GenericAPIView, RetrieveModelMixin, UpdateModelMixin):
    
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
        lookup_field = "pk"
        lookup_url_kwarg = "pk"
    
        # 1：序列化返回单一资源
        def get(self, request, pk):
            return self.retrieve(request, pk)
    
        # 2：反序列化更新（全更新与部分更新）
    
        def put(self, request, pk):
            return self.update(request, pk)
    
        def patch(self, request, pk):
            return self.partial_update(request, pk)

5：反序列化删除单一资源：（DestroyModelMixin）  
5.1：DestroyModelMixin做了什么？

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzQxNzU3_size_16_color_FFFFFF_t_70_pic_center 4]  
5.2：继承之后的代码：

class BookView(GenericAPIView, RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin):
    
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
        lookup_field = "pk"
        lookup_url_kwarg = "pk"
    
        # 1：序列化返回单一资源
        def get(self, request, pk):
            return self.retrieve(request, pk)
    
        # 2：反序列化更新（全更新）
    
        def put(self, request, pk):
            return self.update(request, pk)
    
        def patch(self, request, pk):
            return self.partial_update(request, pk)
    
        # 3:删除单一资源
        def delete(self, request, pk):
            return self.destroy(request, pk)

此时我们发现，只剩下视图函数，那么与没有不用写视图函数的呢？  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzQxNzU3_size_16_color_FFFFFF_t_70_pic_center 5]

## 二：五大子类： ##

from books.models import BookInfo
    from serializers import BookInfoModelSerializers
    from rest_framework.generics import ListAPIView, CreateAPIView
    from rest_framework.generics import RetrieveAPIView,UpdateAPIView, DestroyAPIView
    
    class BooksView(ListAPIView, CreateAPIView):
        # 定义类属性
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
        
    class BookView(RetrieveAPIView, ListAPIView, CreateAPIView, UpdateAPIView, DestroyAPIView):
    
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
        lookup_field = "pk"
        lookup_url_kwarg = "pk"

## 三：视图集ViewSetMixin： ##

功能：django默认get请求，找get方法，能不能有一种途径，能够让get方法找我们自定义的方法呢？

案例一：  
1：定义一个视图：

from rest_framework.viewsets import ViewSetMixin
    
    from books.models import BookInfo
    from serializers import BookInfoModelSerializers
    
    
    class BookView(ViewSetMixin, GenericAPIView):
    
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
    
        def mylist(self, request, *args, **kwargs):
            books = self.get_queryset()
            serializer = self.get_serializer(instance=books, many=True)
            return Response(data=serializer.data)

2：配置路由：

re_path(r"^books/$", BookView.as_view({
        "get": "mylist"}))

案例二：ModelViewSet的使用：  
modelsViewSet的继承关系：  
源码分析：ViewSetMixin:可以自定义的视图集，GenericAPIView是继承于APIview的基类。所以ModelViewSet是我们所有类的子类，继承所有类。  
![在这里插入图片描述][20200922195722490.png_pic_center]  
![在这里插入图片描述][2020092219574572.png_pic_center]

from rest_framework.viewsets import ViewSetMixin, ModelViewSet
    from books.models import BookInfo
    from serializers import BookInfoModelSerializers
    class BookView(ModelViewSet):
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers

路由：

urlpatterns = [
        path('admin/', admin.site.urls),
        re_path(r"^books/$", BookView.as_view({
        "get": "list", "post": "create"})),
        re_path(r"^books/(?P<pk>\d+)/$", BookView.as_view({
        
            "get": "retrieve",
            "put": "update",
            "patch": "partial_update",
            "delete": "destroy",
        }))
    ]

## 四：ReadOnlyModelViewSet: ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzQxNzU3_size_16_color_FFFFFF_t_70_pic_center 6]

## 五：ViewSet: ##

![在这里插入图片描述][20200922202307766.png_pic_center]

## 六：自定义视图函数： ##

from rest_framework.response import Response
    from rest_framework.viewsets import  ModelViewSet
    
    from books.models import BookInfo
    from serializers import BookInfoModelSerializers
    class BookView(ModelViewSet):
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializers
    
        def latest(self, request, *args, **kwargs):
            book = self.queryset.latest('bpub_date')
            serializers = self.get_serializer(instance=book)
            return Response(data=serializers.data)

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