python3-开发进阶Django中序列化以及rest_framework的序列化，,一、django框架

python3-开发进阶Django中序列化以及rest_framework的序列化，,一、django框架

一、django框架的序列化

直接上代码

1、这是app下的models.py

from django.db import models# Create your models here.class Course(models.Model):    title=models.CharField(max_length=32)

2、这是app下的view.py，两种序列化方法

from django.views import Viewfrom app01.models import Courseclass CourseView(View):    def get(self,request):        ret=Course.objects.all()        #这是我们自己用json模块去序列化数据        #import json        #temp=[]         # for i in ret:        #     temp.append({        #         "title":i.title        #    })        #这是django自带的         from django.core.serializers import serialize         ret=serialize("json",ret)         # return HttpResponse(temp)              return HttpResponse(ret)

总结：

　　我们会发现序列化出来的数据比较单一，返回来的样式太麻烦，而django自带的方法，而且无法反序列化!

二、rest_framework中的序列化组件

首先我们要先下载这个模块

pip3 install djangorestframework

装好之后，不要忘了在app中注册rest_framework，

from rest_framework.views import APIViewfrom rest_framework.response import Responsefrom .models import *from django.shortcuts import HttpResponsefrom rest_framework import serializersclass BookSerializers(serializers.Serializer):      title=serializers.CharField(max_length=32)    price=serializers.IntegerField()    pub_date=serializers.DateField()    publish=serializers.CharField(source="publish.name")    #authors=serializers.CharField(source="authors.all")    authors=serializers.SerializerMethodField()    def get_authors(self,obj):        temp=[]        for author in obj.authors.all():            data=[]
　　　　　　　data.append(author.pk)　
　　　　　　　data.append(author.name)
　　　　　　　temp.append(data)        return tempclass BookViewSet(APIView):    def get(self,request,*args,**kwargs):        book_list=Book.objects.all()          bs=BookSerializers(book_list,many=True)        return Response(bs.data)

我们这里有更简便的方法：

from rest_framework import serializersfrom app01.models import Bookclass BookSerializers(serializers.ModelSerializer):    class Meta:        model=Book        fields="__all__"

五种状态的标准形式

class BookView(APIView):    def get(self, request):        book_list = Book.objects.all()        bs = BookSerializers(book_list, many=True)        # 序列化数据        return Response(bs.data)    def post(self, request):        # 添加一条数据        print(request.data)        bs=BookSerializers(data=request.data)        if bs.is_valid():            bs.save()  # 生成记录            return Response(bs.data)        else:            return Response(bs.errors)class BookDetailView(APIView):    def get(self,request,pk):        book_obj=Book.objects.filter(pk=pk).first()        bs=BookSerializers(book_obj,many=False)        return Response(bs.data)    def put(self,request,pk):        book_obj = Book.objects.filter(pk=pk).first()        bs=BookSerializers(data=request.data,instance=book_obj)#instance        if bs.is_valid():            bs.save() # update            return Response(bs.data)        else:            return Response(bs.errors)    def delete(self,request,pk):        Book.objects.filter(pk=pk).delete()        return Response("")

我们再创建一张表，我们会发现代码有点冗余了，除了变量名的变化，这里也有封好的方法mixin类

from rest_framework import mixinsfrom rest_framework import genericsclass BookViewSet(mixins.ListModelMixin,                  mixins.CreateModelMixin,                  generics.GenericAPIView):    queryset = Book.objects.all()    serializer_class = BookSerializers    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 BookDetailViewSet(mixins.RetrieveModelMixin,                    mixins.UpdateModelMixin,                    mixins.DestroyModelMixin,                    generics.GenericAPIView):    queryset = Book.objects.all()    serializer_class = BookSerializers    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)

我们在上面的几个类中，我们下来翻看源码：

from rest_framework.mixins import CreateModelMixinfrom rest_framework.mixins import ListModelMixinfrom rest_framework.mixins import DestroyModelMixinfrom rest_framework.mixins import RetrieveModelMixinfrom rest_framework.mixins import UpdateModelMixin

我们先来看CreateModeMixin类的源码，我们发现 create

ListModeMixin类的源码，我们发现list

RetrieveModelMixin类的源码，我们发现retrieve

UpdateModelMixin类的源码，我们发现update

DestroyModelMixin类的源码，我们发现destroy

然后我们可以这样封装：

from rest_framework.mixins import CreateModelMixin,ListModelMixin,DestroyModelMixin,RetrieveModelMixin,UpdateModelMixinfrom rest_framework import genericsclass BookView(CreateModelMixin,ListModelMixin,generics.GenericAPIView,):    queryset=Book.objects.all()    serializer_class=BookSerializers    def get(self,request):        return self.list(request)    def post(self,request):        return self.create(request)class BookDetailView(DestroyModelMixin,UpdateModelMixin,RetrieveModelMixin,generics.GenericAPIView,):    queryset = Book.objects.all()    serializer_class = BookSerializers    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)

发现代码还是冗余的，我们还有更简便的方法，REST框架提供了简化的view.py模块

from rest_framework import mixinsfrom rest_framework import genericsclass BookViewSet(generics.ListCreateAPIView):    queryset = Book.objects.all()    serializer_class = BookSerializersclass BookDetailViewSet(generics.RetrieveUpdateDestroyAPIView):    queryset = Book.objects.all()    serializer_class = BookSerializersclass PublishViewSet(generics.ListCreateAPIView):    queryset = Publish.objects.all()    serializer_class = PublshSerializersclass PublishDetailViewSet(generics.RetrieveUpdateDestroyAPIView):    queryset = Publish.objects.all()    serializer_class = PublshSerializers

需要什么样的方法，就继承什么方法类，但里面的方法需要在url传入需要的参数

#views中代码非常简介，最重要的还是urlsfrom rest_framework.viewsets import ModelViewSetclass AuthorModelView(ModelViewSet):    queryset=Author.objects.all()    serializer_class=AuthorSerializers

from django.conf.urls import urlfrom django.contrib import adminfrom app01 import viewsurlpatterns = [    url(r‘^admin/‘, admin.site.urls),    #在as_view中加入参数    url(r‘^authors/$‘, views.AuthorModelView.as_view({"get":"list","post":"create"})),    url(r‘^authors/(?P<pk>\d+)/$‘, views.AuthorModelView.as_view({"get":"retrieve","put":"update","delete":"destroy"})),
]

python3-开发进阶Django中序列化以及rest_framework的序列化