restframework 视图

重要知识点

as_view()获取的是view方法名，当url配版成功，执行view方法

一、逻辑封装（mixins, generics）

    path('author/', views.AuthorView.as_view()),
    path('author/<pk>/', views.AuthorDetailView.as_view()),

from rest_framework import mixins, generics
"""
本质：封装逻辑
1.return 父类的方法
2.queryset serializer_class 两个参数必要（看源码）
3.mixins.ListModelMixin和mixins.CreateModelMixin 没有的方法到generics.GenericAPIView去找
4.url的参数要改成pk，根据get_obj() 源码
"""


class AuthorView(mixins.ListModelMixin, mixins.CreateModelMixin, generics.GenericAPIView):
    queryset = Author.objects.all()
    # print(queryset)
    serializer_class = AuthorModelSerializer

    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        return self.create(request, *args, **kwargs)


class AuthorDetailView(mixins.RetrieveModelMixin, mixins.UpdateModelMixin, mixins.DestroyModelMixin,
                       generics.GenericAPIView):
    queryset = Author.objects.all()
    serializer_class = AuthorModelSerializer

    def 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)

二、封装类（generics）

    path('author/', views.AuthorView.as_view()),
    path('author/<pk>/', views.AuthorDetailView.as_view()),

from rest_framework import generics
"""
本质：对类进行封装(具体情况看源码)
1.只需要 queryset 和 serializer_class
2.generics.ListCreateAPIView -----> mixins.ListModelMixin, mixins.CreateModelMixin, GenericAPIView 和get post方法
3.generics.RetrieveUpdateDestroyAPIView -----> mixins.RetrieveModelMixin,mixins.UpdateModelMixin,mixins.DestroyModelMixin, GenericAPIView 和 get put patch 和delete
"""


class AuthorView(generics.ListCreateAPIView):
    queryset = Author.objects.all()
    serializer_class = AuthorModelSerializer


class AuthorDetailView(generics.RetrieveUpdateDestroyAPIView):
    queryset = Author.objects.all()
    serializer_class = AuthorModelSerializer

三、一个视图CBV

有两个视图的原因：有两个get方法

    path('author/', views.AuthorViewSet.as_view({'get': 'list', 'post': 'create'})),
    path('author/<pk>/', views.AuthorViewSet.as_view({'get': 'retrieve', 'put': 'update', 'delete': 'destroy'})),

from rest_framework import viewsets

"""
重点：有两个视图CBV的原因，有两个get方法
源码分析
1.查找as_view()，并传递参数 {'get': 'list', 'post': 'create'}
AuthorViewSet-->ModelViewSet-->GenericViewSet-->ViewSetMixin(找到as_view(传递参数action)，返回值view, 找返回值)-->view()(找到view)

for method, action in actions.items():    actions: {'get': 'list', 'post': 'create'}
    handler = getattr(self, action)     handler=self.list handler=self.create
    setattr(self, method, handler)    self.get=handler=self.list ->self.get=self.list

返回 dispatch()

2.查找 dispatch()
AuthorViewSet-->ModelViewSet-->GenericViewSet-->generics.GenericAPIView-->views.APIView
找到dispatch(self, request, *args, **kwargs)

if request.method.lower() in self.http_method_names:  get 在 方法里
    handler = getattr(self, request.method.lower(),      get既是list 
                      self.http_method_not_allowed)
else:
    handler = self.http_method_not_allowed

get找到list解决了 有两个list的问题
"""


class AuthorViewSet(viewsets.ModelViewSet):
    queryset = Author.objects.all()
    serializer_class = AuthorModelSerializer