初撩Django-RESTful-rest_framework序列化（将模型序列化为JSON）

官方网站：

https://www.django-rest-framework.org/

翻译网站：
https://q1mi.github.io/Django-REST-framework-documentation/

RESTful 在Django框架中实现的插件：rest_framework

在Django框架中RESTful主要表现在序列化的实现、视图函数的实现和urls路由的实现，在这里我们可能会完全推翻Django基础知识中实现代码的方式。

1. 安装：

pip install djangorestframework

2. 在Django中的配置：

　　1. settings.py中INSTALLED_APPS添加['rest-framework',]

　　2.在应用中创建Serializers.py

3.Serializers中三个基础的序列化类:

• serializers.HyperLinkedModelSerializer:序列化模型，并添加超链接
• serializers.Serializer：手动添加序列化
• serializers.ModelSerializer：自动序列化，只需要把模型导入，属性many=True 表示可序列化多个模型

3.1 。serializers.HyperLinkedModelSerializer：

# models.py
from django.db import models

class Books(models.Model):
    b_name = models.CharField(max_length=30)
    b_price = models.FloatField(default=1)

    def to_dict(self):    
        return {'id':self.id, 'b_name':self.b_name, 'b_price':self.b_price}

# urls.py
from django.urls import include, path
from rest_framework import routers

from REST import views


router = routers.DefaultRouter()
router.register(r'Books', views.BookViewSet)

urlpatterns = [
    path('', include(router.urls)),
]

from django.shortcuts import render

# Create your views here.
from rest_framework import viewsets

from REST.models import Books
from REST.serializers import BookSerializer



class BookViewSet(viewsets.ModelViewSet):
    queryset = Books.objects.all()
    serializer_class = BookSerializer

# serializers.py
from rest_framework import serializers

from REST.models import Books


class BookSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Books
        fields = ('url', 'b_name','b_price')

models.py : 建立模型

urls.py :建立路由

views.py :建立序列化类视图

serializers.py :序列化

3.2 。serializers.Serializer

class Person(models.Model):
    p_name = models.CharField(max_length=32)
    p_age = models.IntegerField(default=1)
    p_sex = models.BooleanField(default=False)

    class Meta:
        db_table = 'Person'

from django.urls import  path
from REST import views


urlpatterns = [
    path('person', views.PersonView.as_view()),
]

class PersonView(View):
    def post(self,request):
        p_name = request.POST.get('p_name')
        p_age = request.POST.get('p_age')
        print('*********',p_name)

        person = Person()
        person.p_name = p_name
        person.p_age = p_age
        print('***##***', p_name)
        person.save()

        person_serializer = PersonSerializer(person)
        return JsonResponse(person_serializer.data)

class PersonSerializer(serializers.Serializer):
    # 和模型中的字段对应
    id = serializers.IntegerField(read_only=True)  # 表示只读
    p_name = serializers.CharField(max_length=32)
    p_age = serializers.IntegerField(default=1)
    p_sex = serializers.BooleanField(default=False)

    #  进行对象的创建
    def create(self,validated_data):
        return Person.objects.create(**validated_data)

    # 对象的更新
    def update(self, instance, validated_data):
        # 分别拿到对象，并对对象进行更新
        instance.p_name = validated_data.get('p_name',instance.p_name)
        print('@@@@@@')
        instance.p_age = validated_data.get('p_age', instance.p_age)
        instance.p_sex = validated_data.get('p_sex', instance.p_sex)
        instance.save()

        return instance

3.3 。serializers.ModelSerializer

class StudentSerializer(serializers.ModelSerializer):
    class Meta:
        model = Students
        fields = ('s_name', 's_age')

（省略了models.py,urls.py,views.py,和serializers.Serializer类似）ModelSerializer简单，常用！！！