drf知识--05

两个视图基类

# APIView：之前一直在用---》drf提供的最顶层的父类---》以后所有视图类，都继承自它
# GenericAPIView：继承自APIView--》封装

继承APIView+序列化类+Response写接口

# urls.py--总路由
from django.contrib import admin
from django.urls import path,include
from app01 import views
urlpatterns = [path('admin/', admin.site.urls),path('app/',include('app01.urls'))]# urls.py--子路由app01
from django.contrib import admin
from django.urls import path, include
from . import views
urlpatterns = [path('books/', views.BookView.as_view()),path('books/<int:pk>', views.BookDetailView.as_view()),]

# 序列化类
from rest_framework import serializers
from .models import Bookclass 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},}

# models.py
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

# views.py
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+序列化类+Response写接口

# 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()
# 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
   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_class
queryset            # 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
调用 .all ，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
后期可在子类中重写get_serializer_class，返回什么序列化类就以哪个序列化类做序列化

get_object：获取单条，根据它：lookup_field 获取
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'
# 对象属性查找顺序：

在类中定义了属性，对象中放入了属性
self.属性用的对象自己的，如果对象中没放：self.属性用了类的

# 总结：
# urls.py
urlpatterns = [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()),
]
# serializer.py
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},}
class PublishSerializer(serializers.ModelSerializer):class Meta:model = Publishfields = "__all__"
# views.py
from rest_framework.generics import GenericAPIView
from .models import Publish
from .serializer import PublishSerializerclass BookView(GenericAPIView):queryset = Book.objects.all()serializer_class = BookSerializerdef get(self, request):object_list = self.get_queryset()  # 获取所有要序列化的数据ser = self.get_serializer(instance=object_list, many=True)  # 获取序列化类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):obj = self.get_object()  # 获取单挑---》内部就是按pk从request中取，取出pk对应的值，查询的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('')

5个视图扩展类

# 继承 GenericAPIView+5个视图扩展类+序列化类+Response

# views.py
from rest_framework.mixins import CreateModelMixin, ListModelMixin, RetrieveModelMixin, UpdateModelMixin, \DestroyModelMixinclass BookView(GenericAPIView, CreateModelMixin, ListModelMixin):queryset = Book.objects.all()serializer_class = BookSerializerdef get(self, request):return super().list(request)def post(self, request):# 做保存，加了这一句---》目的是：子类可以重写,增强扩展性# self.perform_create(serializer)return super().create(request)class BookDetailView(GenericAPIView, RetrieveModelMixin, DestroyModelMixin, UpdateModelMixin):queryset = Book.objects.all()serializer_class = BookSerializerdef put(self, request, *args, **kwargs):return super().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)

9个视图子类

# CreateAPIView继承了 GenericAPIView, CreateModelMixin，写了post方法

views.py
from rest_framework.generics import CreateAPIView, ListAPIView
from rest_framework.generics import RetrieveAPIView, DestroyAPIView, UpdateAPIView
from rest_framework.generics import ListCreateAPIView
from rest_framework.generics import RetrieveUpdateDestroyAPIView, RetrieveDestroyAPIView, RetrieveUpdateAPIView
# from rest_framework.generics import DestroyUpdateAPIView # 一般不存在，所以就没有# 实现新增,查所有和查询一条
class BookView(ListCreateAPIView):# 配置两个类属性queryset = Book.objects.all()serializer_class = BookSerializerclass BookDetailView(RetrieveAPIView):queryset = Book.objects.all()serializer_class = BookSerializer

视图集

# views.py
from rest_framework.viewsets import ModelViewSet
class BookView(ModelViewSet):queryset = Book.objects.all()serializer_class = BookSerializer

urls.py
path('books/', views.BookView.as_view({'get':'list','post':'create'})),
path('books/<int:pk>', views.BookView.as_view({'get':'retrieve','put':'update','delete':'destroy'})),