两个视图基类
APIView和GenericAPIView
drf提供的最顶层的父类就是APIView,以后所有的类都继承自他
GenericAPIView继承自APIView,他里面封装了一些工能
基于APIView+ModelSerializer+Resposne写5个接口
子路由:app01>>>urls.py
from django.urls import path, include
from . import viewsurlpatterns = [path('books/', views.BookView.as_view()),path('books/<int:pk>', views.BookDetailView.as_view()),path('publish/', views.PublishView.as_view()),path('publish/<int:pk>', views.PublishDetailView.as_view()),
]主路由:
from django.contrib import admin
from django.urls import path, includeurlpatterns = [path('admin/', admin.site.urls),path('api/v1/', include('app01.urls')),
]
序列化类:
class BookSerializer(serializers.ModelSerializer):class Meta:model = Bookfields = ['id', 'name', 'price', 'publish', 'authors', 'publish_detail', 'author_list']extra_kwargs = {'publish': {'write_only': True},'authors': {'write_only': True},'publish_detail': {'read_only': True},'author_list': {'read_only': True}}
模型表:
from django.db import modelsclass Book(models.Model):name = models.CharField(max_length=32)price = models.DecimalField(max_digits=5, decimal_places=2)publish = models.ForeignKey(to='Publish', on_delete=models.CASCADE)authors = models.ManyToManyField(to='Author')@propertydef publish_detail(self):return {'name': self.publish.name, 'city': self.publish.city}@propertydef author_list(self):l = []for author in self.authors.all():l.append({'name': author.name, 'age': author.age})return ldef __str__(self):return self.nameclass Author(models.Model):name = models.CharField(max_length=32)age = models.IntegerField()author_detail = models.OneToOneField(to='AuthorDetail', on_delete=models.CASCADE)def __str__(self):return self.nameclass AuthorDetail(models.Model):telephone = models.BigIntegerField()birthday = models.DateField()addr = models.CharField(max_length=64)class Publish(models.Model):name = models.CharField(max_length=32)city = models.CharField(max_length=32)email = models.EmailField()def __str__(self):return self.nameclass Meta:verbose_name = '出版社'verbose_name_plural = verbose_name
视图类:
# 第一层:继承APIView+序列化类+Response写接口
class BookView(APIView):def get(self, request):book_list = Book.objects.all()ser = BookSerializer(instance=book_list, many=True)return Response(ser.data)def post(self, request):ser = BookSerializer(data=request.data)if ser.is_valid():ser.save()return Response(ser.data)else:return Response(ser.errors)class BookDetailView(APIView):def put(self,request,*args,**kwargs):book = Book.objects.filter(pk=kwargs.get('pk')).first()ser = BookSerializer(instance=book,data=request.data)if ser.is_valid():ser.save()return Response(ser.data)else:return Response(ser.errors)def get(self,request,*args,**kwargs):book = Book.objects.filter(pk=kwargs.get('pk')).first()ser = BookSerializer(instance=book)return Response(ser.data)def delete(self,request,*args,**kwargs):Book.objects.filter(pk=kwargs.get('pk')).delete()return Response('')
继承GenericAPIView,编写五个接口
class BookView(GenericAPIView):# 配置两个类属性queryset = Book.objects.all()serializer_class = BookSerializerdef get(self, request):obj_list = self.get_queryset()ser = self.get_serializer(instance=obj_list, many=True)return Response(ser.data)def post(self, request):ser = self.get_serializer(data=request.data)if ser.is_valid():ser.save()return Response(ser.data)else:return Response(ser.errors)class BookDetailView(GenericAPIView):queryset = Book.objects.all()serializer_class = BookSerializerdef put(self, request, *args, **kwargs):# book = Book.objects.filter(pk=kwargs.get('pk')).first()obj = self.get_object() # 获取单条数据ser = self.get_serializer(instance=obj, data=request.data)if ser.is_valid():ser.save()return Response(ser.data)else:return Response(ser.errors)def get(self, request, *args, **kwargs):obj = self.get_object()ser = self.get_serializer(instance=obj)return Response(ser.data)def delete(self, request, *args, **kwargs):self.get_object().delete()return Response('')
继承GenericAPIView+序列化类+Response写接口
#1 继承GenericAPIView的写法-1 在类中,写两个类属性:所有数据,序列化类queryset = Book.objects.all()serializer_class = BookSerializer-2 获取所有要序列化的数据self.get_queryset()-3 获取序列化类self.get_serializer(参数跟之前一样)-4 获取单挑self.get_object()# 2 如果想快速写出Publish的5个接口,只需要修改视图类上的两个类属性即可,其他的不用动queryset = Publish.objects.all()serializer_class = PublishSerializer
# GenericAPIView源码分析-1 继承了APIView-2 有些类属性--》目前只记住两个queryset,serializer_classqueryset # 要序列化的所有数据serializer_class # 序列化类lookup_field = 'pk' # 查询单条,前端传入的参数对应值【pk】,转换器filter_backends # 后续要学的,过滤pagination_class # 后续要学的,分页-3 有些对象方法-get_queryset: 返回待序列化的数据1 调用 .all 2 在子类中重写,控制要序列化的数据-get_serializer: 返回 序列化类 以后用它-本质就是---》 self.serializer_class(instance=object_list, many=True) -内部调用了:self.get_serializer_class-后期在子类中重写get_serializer_class,返回什么序列化类,以后就以哪个序列化类做序列化- get_serializer_class 它是用来重写的def get_serializer_class(self):if self.request.method=='GET':return '序列化的类'else:return '反序列化的类'-get_object 获取单条---》根据它:lookup_field 获取
五个视图扩展类
继承GenericAPIView+5个视图扩展类+序列化类+Response
# 第三层:继承GenericAPIView+5个视图扩展类+序列化类+Response
from rest_framework.mixins import CreateModelMixin, ListModelMixin, RetrieveModelMixin, UpdateModelMixin,DestroyModelMixinclass BookView(GenericAPIView, CreateModelMixin, ListModelMixin):# 配置两个类属性queryset = Book.objects.all()serializer_class = BookSerializerdef get(self, request):return super().list(request)def post(self, request):return super().create(request)class BookDetailView(GenericAPIView, RetrieveModelMixin, DestroyModelMixin, UpdateModelMixin):queryset = Book.objects.all()serializer_class = BookSerializerdef put(self, request, *args, **kwargs):return super(BookDetailView, self).update(request, *args, **kwargs)def get(self, request, *args, **kwargs):return super().retrieve(request, *args, **kwargs)def delete(self, request, *args, **kwargs):return super().destroy(request, *args, **kwargs)
九个视图子类
这九个是视图子类,不需要额外继承GenericAPIView,只需要继承9个中其中某个,就会有某个或某几个接口,可以点击ListAPIView源码分析可知,该视图类有一个get方法,返回是一个list;该类继承的是GenericAPIView,父类有的方法,子类都可以使用,所以不再需要额外继承GenericAPIView
""" 基于上面再封装成九个视图类"""
from rest_framework.generics import ListAPIView, CreateAPIView, ListCreateAPIView
from rest_framework.generics import RetrieveAPIView, UpdateAPIView, DestroyAPIView, RetrieveDestroyAPIView, \RetrieveUpdateAPIView, RetrieveUpdateDestroyAPIView # 没有DestroyUpdateAPIView方法,前提是没有查询删除不了# 查询图书所有
class BookListView(ListAPIView):queryset = Book.objects.all()serializer_class = BookSerializer# 图书新增
class BookCreateView(CreateAPIView):queryset = Book.objects.all()serializer_class = BookSerializer# 图书修改
class BookUpdateView(UpdateAPIView):queryset = Book.objects.all()serializer_class = BookSerializer# 查询图书单条
class BookRetrieveView(RetrieveAPIView):queryset = Book.objects.all()serializer_class = BookSerializer# 删除图书
class BookDestroyView(DestroyAPIView):queryset = Book.objects.all()serializer_class = BookSerializer# 图书查询和删除功能
class BookRetrieveDestroyView(RetrieveDestroyAPIView):queryset = Book.objects.all()serializer_class = BookSerializer# 图书查询和修改功能
class BookRetrieveUpdateView(RetrieveUpdateAPIView):queryset = Book.objects.all()serializer_class = BookSerializer# 图书查询、修改和删除
# 查询图书单条
class BookRetrieveUpdateDestroyView(RetrieveUpdateDestroyAPIView):queryset = Book.objects.all()serializer_class = BookSerializer""" 总结:
ListAPIView + CreateAPIView = ListCreateAPIView 给BookView继承的
RetrieveAPIView + DestroyAPIView = RetrieveDestroyAPIView 给BookDetailView视图提供的
RetrieveAPIView + UpdateAPIView = RetrieveDestroyAPIView 给BookDetailView视图提供的
RetrieveAPIView + UpdateAPIView + DestroyAPIView = RetrieveUpdateDestroyAPIView 给BookDetailView视图提供的发现Destroy 和Update 方法没有整合,"""
最终通过继承可以写成下面两个类
""" 将上述的功能再整合一起"""
# 路由urlpatterns = [path('books/', views.BookView.as_view()),path('books/<int:pk>/', views.BookView.as_view()),
]# 视图class BookAPIView(ListCreateAPIView):# 查询所有和新增一个queryset = Book.objects.all()serializer_class = BookSerializerclass BookDetailView(RetrieveUpdateDestroyAPIView): # 查询单条、更新和删除queryset = Book.objects.all()serializer_class = BookSerializer
基于ModelViewSet继承,编写5个类
要编写五个接口,对应写两个视图类,配置两条路由,通过观察发现连个视图类的代码几乎一模一样,我们借此引入了ModelViewSet类,继承自GenericAPIView,继承它只需要编写一个视图类
改变了路由写法—>
path('books/', views.BookAPIView.as_view({'get':'list','post':'create'})),path('books/<int:pk>', views.BookAPIView.as_view({'get':'retrieve','put':'update','delete':'destroy'})),
在路由里面指名两个get方法分别对应的类具体方法,当是get请求,访问这个地址,就执行视图类的list方法或retrieve方法
视图类:
from rest_framework.viewsets import ModelViewSetclass BookAPIView(ModelViewSet):queryset = Book.objects.all()serializer_class = BookSerializer
点开ModelViewSet源码可知,ModelViewSet封装了ListAPIView、 CreateAPIView、RetrieveAPIView、UpdateAPIView、DestroyAPIView,直接继承ModelViewSet可以直接使用create、list、retrieve、destroy和update五种方法,但是我们查询单表和多条都是get的方法,所以需要在路由指名两个路由的get方法分别对应内置的方法( path(‘books/’, views.BookAPIView.as_view({‘get’: ‘list’, ‘post’: ‘create’})))
ViewSetMixin源码分析
只要是继承了ViewSetMixin,路由写法就变了
ViewSetMixin,不是视图类,支持路由映射的写法,核心原理是重写了as_view
请求来了:
原来:执行APIView的as_view内的view(request)
现在:执行ViewSetMixin的as_view内的view(request)
class ViewSetMixin: @classonlymethoddef as_view(cls, actions=None, **initkwargs):# actions={'get':'list','post':'create'}def view(request, *args, **kwargs):self = cls(**initkwargs) # self是BookView 视图类的对象if 'get' in actions and 'head' not in actions:actions['head'] = actions['get']self.action_map = actionsfor method, action in actions.items():# 每次循环都是method:get,actions:list# 去视图类对象中self反射list方法# handler就是BookView的对象中的list方法handler = getattr(self, action)# 反射,设置值,把method:get,设置成list方法# BookView类的对象,以后就是get方法也就是list方法setattr(self, method, handler)return self.dispatch(request, *args, **kwargs)# 根据请求方式执行跟请求方式同名的方法,get请求-----》》》get方法
ViewSetMixin的总结
以后路由写法as_view()必须传入字典,写成映射关系
什么请求方式,就会去执行视图类中什么方法,根据映射关系去执行
以后只要继承了APIView,但是路由写法变化,就要继承ViewSetMixin
以后只要继承了GenericAPIView,但是路由写法变化,就要继承ViewSetMixin
视图类
# ViewSetMixin必须在APIView的前面
class UserView(ViewSetMixin, APIView):def login(self, reqeust):return Response('login')路由
path('users/', views.UserView.as_view({'post':'login'})),
ReadOnlyModelViewSet(只读)
也是继承了GenericAPIView,但是内部封装的方法只有两个list、retrieve,只查询,查询单条和所有
路由写法也改变了
只能写两个方法,写多个会报错path('books/', views.BookAPIView.as_view({'get':'list'})),path('books/<int:pk>', views.BookAPIView.as_view({'get':'retrieve'})),
drf之路由
视图类没有继承了ViewSetMixin,路由写法跟之前一样
path('books/', views.BookView.as_view())
只要视图类继承了ViewSetMixin,路由写法必须写成映射的方式
path('books/', views.BookView.as_view({'get': 'list'})),
只要视图类继承了ModelViewSet,还可以这么写
# 导入
from rest_framework.routers import SimpleRouter# 实例化
router=SimpleRouter()# 注册
router.register('books',views.BookAPIView,'books')
# 这句话就是相当于写了这两句
path('books/', views.BookAPIView.as_view({'get':'list','post':'create'})),
path('books/<int:pk>', views.BookAPIView.as_view({'get':'retrieve','put':'update','delete':'destroy'})),# 添加到路由中
urlpatterns += router.urls
假如视图类中有个login,如何应对
from rest_framework.decorators import actionclass BookAPIView(ModelViewSet):queryset = Book.objects.all()serializer_class = BookSerializer# 手动映射# methods=None,请求方式# detail=None,只能写True或False,如果写了False就是不带pk的路径,如果写了True就是带了pk的路径# url_path=None,路径,会在之前的路径上,拼上这个路径,如果不写默认以函数名拼接# url_path='login' 写了login就会在http://127.0.0.1:8000/api/v1/books/login/,books后面加上login# url_name=None,别名,用作反向解析@action(methods=['POST','GET'], detail=False) # 这个时候就只能POST,GET请求,别的请求不支持def login(self, request):return Response('login')@action(methods=['POST'], detail=False) # 这个时候就只能POST请求,别的请求不支持def register(self, request):return Response('login')
总结
以后只要是继承了ViewSetMixin,就可以使用SimpleRouter方式写路由
#1 导入from rest_framework.routers import SimpleRouter,DefaultRouter#2 实例化 :SimpleRouter,DefaultRouterrouter = SimpleRouter()或:认为他们一样即可---》DefaultRouter多一条路径router = DefaultRouter()#3 注册路径router.register('books', views.BookView, 'books')#4 加入到路由中:# 方式一:(用这个)urlpatterns += router.urls# 方式二:urlpatterns = [path('', include(router.urls)),]# 5 list,create,retrieve,destroy,update--->自动映射--》SimpleRouter# 6 视图类中自己的方法,再做映射--action装饰器@action(methods=['POST'],detail=False,)def login(self,request):return Response('login')
认证组件
登录进系统后,再访问接口信息,需要携带登录信息,如果没携带就不允许访问,这个控制就是认证
之前我们学过cookie(浏览器自带的)和Session(后端存储的键值对)
写个登录
models.py
# 用户表用来做登录
class User(models.Model):username = models.CharField(max_length=64)password = models.CharField(max_length=64)class UserToken(models.Model):user = models.OneToOneField(to='User', on_delete=models.CASCADE)token = models.CharField(max_length=64)
views.py
from .models import User, UserToken
from rest_framework.viewsets import ViewSet
import uuidclass UserView(ViewSet):@action(methods=['POST'], detail=False)def login(self, request):username = request.data.get('username')password = request.data.get('password')user = User.objects.filter(username=username, password=password).first()if user:# 生成随机字符串,放到UserToken表中,把随机字符串返回给前端token = str(uuid.uuid4())# 如果之前UserToken中有数据,就要更新,没有就有新增UserToken.objects.update_or_create(defaults={'token': token}, user_id=user.pk)return Response({'code': 100, 'msg': 'ok', 'token': token})else:return Response({'code': 101, 'msg': 'no'})
app01>>>urls
# 导入
from rest_framework.routers import SimpleRouter# 实例化
router=SimpleRouter()# 注册
# router.register('books',views.BookAPIView,'books')
router.register('users',views.UserView,'users')
urlpatterns = []
# 添加到路由中
urlpatterns += router.urls
每当我提交一次POST请求,token就会刷新,UserToken表里的数据也会刷新
认证组件步骤
1.写一个认证类,继承BaseAuthentication
2.在类中重写 authenticate,在方法中完成认证,如果通过,返回两个值,如果失败,抛异常
def authenticate(self, request):# 完成对用户的校验# 当次请求requesttoken = request.query_params.get('token')# 表中校验user_token = UserToken.objects.filter(token=token).first()# 当前登录用户if user_token:user = user_token.user# 校验过后,返回两个值return user, user_tokenelse:raise AuthenticationFailed("token不合法")
3.是用认证类:需要放在登录后才能访问的视图类上
class BookView(ViewSet,ListCreateAPIView):queryset = Book.objects.all()serializer_class = BookSerializerclass BookDetailView(ViewSet,RetrieveUpdateDestroyAPIView):authentication_classes = [LoginAuth]queryset = Book.objects.all()serializer_class = BookSerializer