【Django】DRF的ViewSet视图集、action装饰器、Routers路由

忘是亡心i 2022-12-10 03:45 146阅读 0赞

#### 1.重要的视图集 ####

<table> 
 <thead> 
  <tr> 
   <th>视图集</th> 
   <th>说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>ViewSetMixin</td> 
   <td>重写<code>self.as_view()</code>函数，传入字典指定请求方式映射的视图函数</td> 
  </tr> 
  <tr> 
   <td>ViewSet</td> 
   <td>继承<code>ViewSetMixin</code>和<code>APIView</code>，提供了身份认证、权限校验、流量管理等</td> 
  </tr> 
  <tr> 
   <td>ModelViewSet</td> 
   <td>继承<code>五大拓展类</code>和<code>GenericAPIView</code>，提供增删改查接口 <br> <code>self.list()</code>、 <code>self.create()</code>、 <code>self.retrieve()</code>、 <code>self.update()</code>、 <code>self.partial_update()</code>、 <code>self.destroy()</code></td> 
  </tr> 
  <tr> 
   <td>GenericViewSet</td> 
   <td>继承<code>ViewSetMixin</code>和<code>GenericAPIView</code></td> 
  </tr> 
  <tr> 
   <td>ReadOnlyModelViewSet</td> 
   <td>继承拓展类<code>RetrieveModelMixin</code>、<code>ListModelMixin</code>和<code>GenericAPIView</code>；提供只读接口 <br> <code>self.list()</code>、 <code>self.create()</code></td> 
  </tr> 
 </tbody> 
</table>

#### 2.action装饰器 ####

Django默认的路由分发规则决定了视图函数只能以get、post等请求方式命名，如果想要使用自定义的方式命名，我们可以使用action去映射请求方法名与自定义方法

views.py

from rest_framework.decorators import action
    from rest_framework.generics import  RetrieveAPIView, UpdateAPIView, DestroyAPIView
    from rest_framework.response import Response
    from rest_framework.viewsets import ModelViewSet
    
    from .models import BookInfo
    from .serializers import BookInfoModelSerializer
    
    # re_path(r'^books/$',views.BooksView.as_view()),
    class BooksView(ModelViewSet):
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializer
    
        # 自定义一个视图函数，需求是获取一本最新的书
        # GET /books/latest/
        # methods: 映射的请求方式
        # url_path：路径拼接尾缀，默认是函数名
        # detail：
        # True：前缀(prefix)+pk正则分组+尾缀(url_path)
        # False：前缀(prefix)+尾缀(url_path)
        @action(methods=['get'],detail=False,url_path='latest')
        def latest(self,request,*args,**kwargs):
            book = self.queryset.latest('bpub_date')
            serializer = self.get_serializer(instance=book)
            return Response(data=serializer.data)
    
    # re_path(r'^book/(?P<pk>\d+)/$',views.BookView.as_view())
    class BookView(RetrieveAPIView,UpdateAPIView,DestroyAPIView):
        queryset = BookInfo.objects.all()
        serializer_class = BookInfoModelSerializer

models.py

from django.urls import path,re_path
    from booktest.views import BooksView
    from . import views
    
    urlpatterns = [
        # re_path(r'^books/$',views.BooksView.as_view()),
        re_path(r'^books/',views.BooksView.as_view({ 'get':'latest'})),
        ...
    ]

**特别注意：** 如果路由列表里使用的是re\_path()，一定要注意不能以$结尾，否则匹配不正确，因为它要与pk或尾缀拼接

#### 3.路由 ####

在ViewSet视图集，我们除了可以使用action进行映射之外，还可以使用Routers路由，DRF主要提供了SimpleRouter和DefaultRouter两种路由

用法

from rest_framework import routers  # 导包
    router = routers.SimpleRouter()  # 使用简单路由
    register(prefix, viewset, base_name)  #注册

参数说明  
`prefix` ：路由前缀  
`viewset`：要被访问的视图集  
`base_name`：路由名称的前缀

改写上面的action路由方式

from django.urls import path,re_path
    from rest_framework.routers import SimpleRouter
    from booktest.views import BooksView
    from . import views
    
    urlpatterns = [
        # re_path(r'^books/$',views.BooksView.as_view()),
        # re_path(r'^books/',views.BooksView.as_view({'get':'latest'})),
        ...
    ]
    
    router = SimpleRouter()  # 实例化一个简单路由
    router.register(prefix='books', viewset=BooksView, base_name='books') # 注册路由
    urlpatterns += router.urls  # 合并到urlpatterns列表里
    # 或 urlpatterns.extend(router.urls)

SimpleRouter和DefaultRouter区别不大，可参考下面两张对比图  
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