view:视图
generics:工具视图
mixins:视图工具集
viewsets:视图集
学习曲线: APIView => GenericAPIView => mixins的五大工具类 => generics中的工具视图 => viewsets中的视图集
一.GenericAPIView基类
# GenericAPIView是继承APIView的，完全兼容APIView
# 重点：GenericAPIView在APIView基础上完成了哪些事?
1）get_queryset()：从类属性queryset中获得model的queryset数据
2）get_object()：从类属性queryset中获得model的queryset数据，再通过有名分组pk确定唯一操作对象
3）get_serializer()：从类属性serializer_class中获得serializer的序列化类
urlpatterns = [
url(r'^v2/books/$', views.BookGenericAPIView.as_view()),
url(r'^v2/books/(?P<pk>.*)/$', views.BookGenericAPIView.as_view()),
]
# BookGenericAPIView.as_view() => 调用的是APIView的as_view() => View的as_view() => APIView的dispatch完成分发
from rest_framework.generics import GenericAPIView
# BookGenericAPIView.as_view() => 调用的是APIView的as_view() => View的as_view() => APIView的dispatch完成分发
class BookGenericAPIView(GenericAPIView):
queryset = models.Book.objects.filter(is_delete=False)
serializer_class = serializers.BookModelSerializer
lookup_field = 'pk' # 单查是要指定lookup_field = 'pk'属性
# 群查:
def get(self, request, *args, **kwargs):
book_query = self.get_queryset() # 会自动将queryset传入,得到model类的queryset对象
book_ser = self.get_serializer(book_query, many=True) # 等同于BookModelSerializer序列化
book_data = book_ser.data
return APIResponse(results=book_data)
# 单查:
def get(self, request, *args, **kwargs):
book_obj = self.get_object() # 会自动将queryset传入,并调用lookup_field属性,得到model类的具体的一条记录(即:对象)
book_ser = self.get_serializer(book_obj)
book_data = book_ser.data
return APIResponse(results=book_data)
二.mixins视图工具集 - 辅助GenericAPIView
# 1）mixins有五个工具类文件，一共提供了五个工具类，六个工具方法：单查、群查、单增、单删、单整体改、单局部改
- 群查 ListModelMixin | list()
- 单查 RetrieveModelMixin | retrieve()
- 单增 CreateModelMixin | create()
- UpdateModelMixin | update()单整体改 | partial_update()单局部改(单删:改字段)
- DestroyModelMixin | destroy() 单删 注意:从数据库中删除,一般不用
# 2）继承工具类可以简化请求函数的实现体，但是必须继承GenericAPIView，需要GenericAPIView类提供的几个类属性和方法(见上方GenericAPIView基类知识点)
属性:
- queryset | model类对象
- serializer_class | 序列化类
- lookup_field | 指定pk
方法:
- get_queryset() | 拿到对象们
- get_object() | 拿到具体的对象
- get_serializer() | 序列化,反序列化
# 3）工具类的工具方法返回值都是Response类型对象，如果要格式化数据格式再返回给前台，可以通过 response.data 拿到工具方法返回的Response类型对象的响应数据
urlpatterns = [
url(r'^v3/books/$', views.BookMixinGenericAPIView.as_view()),
url(r'^v3/books/(?P<pk>.*)/$', views.BookMixinGenericAPIView.as_view()),
]
from rest_framework.mixins import ListModelMixin,RetrieveModelMixin,CreateModelMixin,UpdateModelMixin
class BookMixinGenericAPIView(ListModelMixin, RetrieveModelMixin, CreateModelMixin, UpdateModelMixin, GenericAPIView):
# 继承GenericAPIView的目的:
# 1.路由调用GenericAPIView父类APIView的as_view()方法
# 2.调用APIView的dispatch完成方发
# 3.需要GenericAPIView类提供的几个类属性和方法
queryset = models.Book.objects.filter(is_delete=False)
serializer_class = serializers.BookModelSerializer
def get(self, request, *args, **kwargs):
if 'pk' in kwargs:
# 单查:RetrieveModelMixin 中的retrieve()方法,内部是调用了GenericAPIView的get_object()方法
response = self.retrieve(request, *args, **kwargs)
else:
# 群查:ListModelMixin 中的list()方法,内部是调用了GenericAPIView的get_serializer(queryset, many=True)方法
response = self.list(request, *args, **kwargs)
# mixins提供的方法响应的数据默认是Response
# response.data即可拿到响应的数据
print(response.data) # {'字段':'字段值',...}
return APIResponse(results=response.data)
# 单增:CreateModelMixin 中的create()方法内部是调用了GenericAPIView的get_serializer(data=request.data)方法完成序列化,在保存
def post(self, request, *args, **kwargs):
response = self.create(request, *args, **kwargs)
return APIResponse(results=response.data)
# 单 整体改: UpdateModelMixin 中的update()方法内部是调用了GenericAPIView的get_object()拿到具体对象,使partial=False到达整体改
def put(self, request, *args, **kwargs):
response = self.update(request, *args, **kwargs)
return APIResponse(results=response.data)
# 单 局部改: UpdateModelMixin 中的update()方法内部是调用了GenericAPIView的get_object()拿到具体对象,使partial=True到达局部改
def patch(self, request, *args, **kwargs):
response = self.partial_update(request, *args, **kwargs)
return APIResponse(results=response.data)
三.generics 工具视图
1）工具视图都是GenericAPIView的子类，且不同的子类继承了不同的工具类，重写了请求方法
-- UpdateAPIView: 2）工具视图的功能如果直接可以满足需求，只需要继承工具视图，提供queryset与serializer_class即可
urlpatterns = [
url(r'^v4/books/$', views.BookListCreatePIView.as_view()),
url(r'^v4/books/(?P<pk>.*)/$', views.BookListCreatePIView.as_view()),
]
from rest_framework.generics import ListCreateAPIView, UpdateAPIView
class BookListCreatePIView(ListCreateAPIView, UpdateAPIView):
queryset = models.Book.objects.filter(is_delete=False)
serializer_class = serializers.BookModelSerializer
四.viewsets 视图集
1）视图集都是优先继承ViewSetMixin类，再继承一个视图类（GenericAPIView或APIView）
# GenericViewSet、ViewSet
2）ViewSetMixin提供了重写的as_view()方法，继承视图集的视图类，配置路由时调用as_view()必须传入 {请求名:函数名} 映射关系字典
# eg: url(r'^v5/books/$', views.BookGenericViewSet.as_view({'get': 'my_get_list'})),
# 表示get请求会交给my_get_list视图函数处理
urlpatterns = [
# View的as_view()：将get请求映射到视图类的get方法
# ViewSet的as_view({'get': 'my_get_list'})：将get请求映射到视图类的my_get_list方法
url(r'^v5/books/$', views.BookGenericViewSet.as_view({'get': 'my_get_list'})),
url(r'^v5/books/(?P<pk>.*)/$', views.BookGenericViewSet.as_view({'get': 'my_get_obj'})),
]
from rest_framework.viewsets import GenericViewSet
from rest_framework import mixins
class BookGenericViewSet(mixins.ListModelMixin, mixins.RetrieveModelMixin, GenericViewSet):
queryset = models.Book.objects.filter(is_delete=False)
serializer_class = serializers.BookModelSerializer
# 群查
def my_get_list(self, request, *args, **kwargs):
return self.list(request, *args, **kwargs)
# 单查
def my_get_obj(self, request, *args, **kwargs):
return self.retrieve(request, *args, **kwargs)
GenericAPIView 与 APIView 区别
# GenericAPIView 与 APIView 最为两大继承视图的区别
# 1）GenericViewSet和ViewSet都继承了ViewSetMixin，as_view都可以配置 {请求:函数} 映射关系
# 2）GenericViewSet继承的是GenericAPIView视图类，用来完成标准的 model 类操作接口
# 3）ViewSet继承的是APIView视图类，用来完成不需要 model 类参与，或是非标准的 model 类操作接口
# post请求在标准的 model 类操作下就是新增接口，登陆的post不满足
# post请求验证码的接口，不需要 model 类的参与
# 案例：登陆的post请求，并不是完成数据的新增，只是用post提交数据，得到的结果也不是登陆的用户信息，而是登陆的认证信息
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'''
继承关系:
APIView(View)
GenericAPIView(APIView)
GenericVieaSet(
ViewSetMixin,
generics.GenericAPIView)
ModelViewSet(
mixins.CreateModelMixin,增
mixins.RetreveModelMixin,单查
mixins.UpdateModelMixin,单/整改
mixins.DestroyModelMixin,删
mixins.ListModelMixin,群查
GenericViewSet，路由{}映射
)
CreateAPIView(
mixins.CreateModelMixin,
GenericAPIView
)
ListAPIView(
mixins.ListModelMixin,
GenericAPIView
)
RetrieveAPIView(
mixins.RetrieveModelMixin,
GenericAPIView
)
DestroyAPIView(
mixins.DestroyModelMixin,
GenericAPIView
)
UpdateAPIView(
mixins.UpdateModelMixin,
GenericAPIView
)
ListCreateAPIView(
mixins.ListModelMixin,
mixins.CreateModelMixin,
GenericAPIView
)
RetrieveUpdateAPIView(
mixins.RetrieveModelMixin,
mixins.UpdateModelMixin,
GenericAPIView
)
RetrieveDestroyAPIView(
mixins.RetrieveModelMixin,
mixins.DestroyModelMixin,
GenericAPIView
)
RetrieveUpdateDestroyAPIView(
mixins.RetrieveModelMixin,
mixins.UpdateModelMixin,
mixins.DestroyModelMixin,
GenericAPIView
)
'''
View Code