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 View
from app01.models import Course
class 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 APIView
from rest_framework.response import Response
from .models import *
from django.shortcuts import HttpResponsefrom rest_framework import serializers
class 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 temp
class 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 serializers
from app01.models import Book
class 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 mixins
from rest_framework import generics
class 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 CreateModelMixin
from rest_framework.mixins import ListModelMixin
from rest_framework.mixins import DestroyModelMixin
from rest_framework.mixins import RetrieveModelMixin
from 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,UpdateModelMixin
from rest_framework import generics
class 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 mixins
from rest_framework import generics
class BookViewSet(generics.ListCreateAPIView):
queryset = Book.objects.all()
serializer_class = BookSerializers
class BookDetailViewSet(generics.RetrieveUpdateDestroyAPIView):
queryset = Book.objects.all()
serializer_class = BookSerializers
class PublishViewSet(generics.ListCreateAPIView):
queryset = Publish.objects.all()
serializer_class = PublshSerializers
class 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urls
from rest_framework.viewsets import ModelViewSet
class AuthorModelView(ModelViewSet):
queryset=Author.objects.all()
serializer_class=AuthorSerializers
from django.conf.urls import url
from django.contrib import admin
from app01 import views
urlpatterns = [
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"})),
]
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