ModelSerializer序列化器实战
使用ModelSerializer序列化器如何写接口？这里源码demo都写全了~一看就懂！
ModelSerializer序列化器实战
上篇ModelSerializer序列化器做了一个小demo，演示了如何操作单表进行序列化和反序列化来实现五个API的使用，多表大差不差😁，这里对四个表写五个API接口
单表操作
单表操作序列化类demo：
序列化器类
# ModelSerializer和表模型有绑定关系
class BookSerializer1(serializers.ModelSerializer):
class Meta:
model = Book # 指定和哪个表有关系
# 所有字段
# fields = '__all__'
# 这里注意id字段是从表模型映射过来的，auto自增的，不传也可以
# 自定制的字段不传必须注册，在列表中
fields = ['id', 'title', 'price', 'price_info'] # 指定字段
extra_kwargs = {
'title': {'write_only': True, 'max_length': 8, 'min_length': 3}
}
# 指定序列化的字段：两种写法：在序列化类中写；models中写
price_info = serializers.SerializerMethodField()
def get_price_info(self, obj):
return "价格是：" + str(obj.price)
'''
注意：自定制字段如果和表模型获取到的字段是同名，那么自定制返回给前端的字段值就被自定制覆盖了，比如：
title = serializers.SerializerMethodField()
def get_title(self, obj):
return "书名是：" + str(obj.title)
'''
# 局部和全局钩子，跟之前一样，但是要注意写在Meta外
视图类
from rest_framework.views import APIView
from .models import Book
from rest_framework.response import Response
from app01.serializer import BookSerializer1
class BookView1(APIView):
def get(self, request):
# 从数据库查数据，做序列化
book_list = Book.objects.all()
# 实例化类，传入初始化的参数，instance和many
'''
instance:要序列化的对象 qs，单个对象
many:如果是qs对象，many=True，如果是单个对象many=False
'''
ser = BookSerializer1(instance=book_list, many=True)
# ser.data使用模型类的对象得到序列化后的字典
return Response(ser.data)
def post(self,request):
# 反序列化，保存到数据库使用data参数
deser = BookSerializer1(data=request.data)
# 校验数据
if deser.is_valid():
# 保存需要重写create方法,不然不知道存到哪个表
deser.save()
return Response(deser.data)
return Response({'code':101,'msg':'校验不通过','errors':deser.errors})
# 处理修改再写一个视图类，防止get冲突
class BookDetailView1(APIView):
def get(self,request,pk):
book = Book.objects.filter(pk=pk).first()
ser = BookSerializer1(instance=book) # 这里设置了主键值，单条记录many不需要写
return Response(ser.data)
def delete(self,request,pk):
res = Book.objects.filter(pk=pk).delete()
print(res) # (1, {'app01.Book': 1})
# res是影响的行数
if res[0]>0:
return Response({'code': 100, 'msg': '删除成功'})
else:
return Response({'code': 103, 'msg': '要删除的数据不存在'})
# 反序列化修改
def put(self,request,pk):
# 修改处理单条数据用过pk确定求改哪条数据
book = Book.objects.filter(pk=pk).first()
# 序列化器类实例化需要传入instance，data才表示修改
ser = BookSerializer1(instance=book,data=request.data)
if ser.is_valid():
# 重写update方法才能存入
ser.save()
return Response(ser.data)
return Response({'code':101,'msg':'校验未通过','error':ser.errors})
路由
path('books1/', views.BookView1.as_view()),
path('books1/<int:pk>', views.BookDetailView1.as_view()),
模型
from django.db import models
class Book(models.Model):
title = models.CharField(max_length=32)
price = models.DecimalField(max_digits=5,decimal_places=2)
authors = models.CharField(max_length=32)
多表操作
models.py
from django.db import models
# build four model tables
class Book(models.Model):
name = models.CharField(max_length=32)
price = models.DecimalField(decimal_places=2, max_digits=5)
publish = models.ForeignKey(to='Publish', on_delete=models.CASCADE)
authors = models.ManyToManyField(to='Author')
def __str__(self):
return self.name
# 自定制字段
@property
def publish_detail(self):
return {'name': self.publish.name, 'addr': self.publish.city}
@property
def author_list(self):
l = []
print(self.authors.all()) # <QuerySet [<Author: Author object (1)>, <Author: Author object (2)>]>
for author in self.authors.all():
print(author.author_detail) # AuthorDetail object (1)
l.append({'name': author.name, 'age': author.age, 'addr': author.author_detail.addr})
return l
class 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.name
@property
def authordetail_info(self):
return {'phone':self.author_detail.telephone,'addr':self.author_detail.addr}
class AuthorDetail(models.Model):
telephone = models.BigIntegerField()
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()
serializer.py
from app01 import models
from rest_framework import serializers
# 书序列化器
class BookSerializer(serializers.ModelSerializer):
class Meta:
# 指定和哪个表有关系
model = models.Book
# fields = '__all__'
fields = ['id','name','price','publish','authors','publish_detail','author_list']
# 将关联表的信息全部取出来，不推荐使用
# depth = 1
extra_kwargs = {
'publish':{'write_only':True},
'authors':{'write_only':True}
}
# 作者序列化器
class AuthorSerializer(serializers.ModelSerializer):
class Meta:
# 指定和哪个表有关系
model = models.Author
# fields = '__all__'
fields = ['id', 'name', 'age', 'author_detail', 'authordetail_info']
extra_kwargs = {
'author_detail': {'write_only': True},
}
# 作者详情序列化器
class AuthorDetailSerializer(serializers.ModelSerializer):
class Meta:
# 指定和哪个表有关系
model = models.AuthorDetail
fields = '__all__'
# 出版社序列化器
class PublishSerializer(serializers.ModelSerializer):
class Meta:
# 指定和哪个表有关系
model = models.Publish
fields = '__all__'
views.py
from rest_framework.response import Response
from rest_framework.views import APIView
from app01 import models
from app01 import serializer
# 书视图类
class BookView(APIView):
def get(self, requets):
# 序列化
book_list = models.Book.objects.all()
# 序列化多条数据many=True
ser = serializer.BookSerializer(instance=book_list, many=True)
return Response(ser.data)
def post(self, request):
# 获取反序列化数据
ser = serializer.BookSerializer(data=request.data)
if ser.is_valid():
# 校验通过存入数据库，不需要重写create方法了
ser.save()
return Response({'code': 100, 'msg': '新增成功', 'data': ser.data})
# 校验失败
return Response({'code': 101, 'msg': '校验未通过', 'error': ser.errors})
class BookViewDetail(APIView):
def get(self, request, pk):
book = models.Book.objects.filter(pk=pk).first()
ser = serializer.BookSerializer(instance=book)
return Response(ser.data)
def put(self, request, pk):
book = models.Book.objects.filter(pk=pk).first()
# 修改，instance和data都要传
ser = serializer.BookSerializer(instance=book, data=request.data)
if ser.is_valid():
# 校验通过修改，不需要重写update
ser.save()
return Response({'code:': 100, 'msg': '修改成功', 'data': ser.data})
# 校验不通过
return Response({'code:': 102, 'msg': '校验未通过，修改失败', 'error': ser.errors})
def delete(self, request, pk):
models.Book.objects.filter(pk=pk).delete()
return Response({'code': 100, 'msg': '删除成功'})
# 作者视图类
class AuthorView(APIView):
def get(self, requets):
# 序列化
author_list = models.Author.objects.all()
# 序列化多条数据many=True
ser = serializer.AuthorSerializer(instance=author_list, many=True)
return Response(ser.data)
def post(self, request):
# 获取反序列化数据
ser = serializer.AuthorSerializer(data=request.data)
if ser.is_valid():
# 校验通过存入数据库，不需要重写create方法了
ser.save()
return Response({'code': 100, 'msg': '新增成功', 'data': ser.data})
# 校验失败
return Response({'code': 101, 'msg': '校验未通过', 'error': ser.errors})
class AuthorViewDetail(APIView):
def get(self, request, pk):
book = models.Author.objects.filter(pk=pk).first()
ser = serializer.AuthorSerializer(instance=book)
return Response(ser.data)
def put(self, request, pk):
book = models.Author.objects.filter(pk=pk).first()
# 修改，instance和data都要传
ser = serializer.AuthorSerializer(instance=book, data=request.data)
if ser.is_valid():
# 校验通过修改，不需要重写update
ser.save()
return Response({'code:': 100, 'msg': '修改成功', 'data': ser.data})
# 校验不通过
return Response({'code:': 102, 'msg': '校验未通过，修改失败', 'error': ser.errors})
def delete(self, request, pk):
models.Author.objects.filter(pk=pk).delete()
return Response({'code': 100, 'msg': '删除成功'})
# 作者详情视图类
class AuthorDetailView(APIView):
def get(self, requets):
# 序列化
author_list = models.AuthorDetail.objects.all()
# 序列化多条数据many=True
ser = serializer.AuthorDetailSerializer(instance=author_list, many=True)
return Response(ser.data)
def post(self, request):
# 获取反序列化数据
ser = serializer.AuthorDetailSerializer(data=request.data)
if ser.is_valid():
# 校验通过存入数据库，不需要重写create方法了
ser.save()
return Response({'code': 100, 'msg': '新增成功', 'data': ser.data})
# 校验失败
return Response({'code': 101, 'msg': '校验未通过', 'error': ser.errors})
class OneAuthorViewDetail(APIView):
def get(self, request, pk):
book = models.AuthorDetail.objects.filter(pk=pk).first()
ser = serializer.AuthorDetailSerializer(instance=book)
return Response(ser.data)
def put(self, request, pk):
book = models.AuthorDetail.objects.filter(pk=pk).first()
# 修改，instance和data都要传
ser = serializer.AuthorDetailSerializer(instance=book, data=request.data)
if ser.is_valid():
# 校验通过修改，不需要重写update
ser.save()
return Response({'code:': 100, 'msg': '修改成功', 'data': ser.data})
# 校验不通过
return Response({'code:': 102, 'msg': '校验未通过，修改失败', 'error': ser.errors})
def delete(self, request, pk):
models.AuthorDetail.objects.filter(pk=pk).delete()
return Response({'code': 100, 'msg': '删除成功'})
# 出版社视图类
class PublishView(APIView):
def get(self, requets):
# 序列化
author_list = models.Publish.objects.all()
# 序列化多条数据many=True
ser = serializer.PublishSerializer(instance=author_list, many=True)
return Response(ser.data)
def post(self, request):
# 获取反序列化数据
ser = serializer.PublishSerializer(data=request.data)
if ser.is_valid():
# 校验通过存入数据库，不需要重写create方法了
ser.save()
return Response({'code': 100, 'msg': '新增成功', 'data': ser.data})
# 校验失败
return Response({'code': 101, 'msg': '校验未通过', 'error': ser.errors})
class PublishViewDetail(APIView):
def get(self, request, pk):
book = models.Publish.objects.filter(pk=pk).first()
ser = serializer.PublishSerializer(instance=book)
return Response(ser.data)
def put(self, request, pk):
book = models.Publish.objects.filter(pk=pk).first()
# 修改，instance和data都要传
ser = serializer.PublishSerializer(instance=book, data=request.data)
if ser.is_valid():
# 校验通过修改，不需要重写update
ser.save()
return Response({'code:': 100, 'msg': '修改成功', 'data': ser.data})
# 校验不通过
return Response({'code:': 102, 'msg': '校验未通过，修改失败', 'error': ser.errors})
def delete(self, request, pk):
models.Publish.objects.filter(pk=pk).delete()
return Response({'code': 100, 'msg': '删除成功'})
urls.py
from django.contrib import admin
from django.urls import path
from app01 import views
urlpatterns = [
path('admin/', admin.site.urls),
# 书
path('books/', views.BookView.as_view()),
path('books/<int:pk>', views.BookViewDetail.as_view()),
# 作者
path('authors/', views.AuthorView.as_view()),
path('authors/<int:pk>', views.AuthorViewDetail.as_view()),
# 作者详情
path('authorsdetail/', views.AuthorDetailView.as_view()),
path('authorsdetail/<int:pk>', views.OneAuthorViewDetail.as_view()),
# 出版社
path('publish/', views.PublishView.as_view()),
path('publishdetail/<int:pk>', views.PublishViewDetail.as_view()),
]
优化操作
我们知道作者表和作者详情表的表关系是一对一的关系，那么新增数据的时候，就得先新增作者详情表，再增作者表的数据，但是在实际生活中，用户不知道表关系这码事，为了体验更好，可以重写create方法，同时存两个表的内容，给用户的感觉就是操作了一张表
'''优化作者表的序列化器'''
# 作者序列化器
class AuthorSerializer(serializers.ModelSerializer):
class Meta:
# 指定和哪个表有关系
model = models.Author
# fields = '__all__'
fields = ['id', 'name', 'age', 'telephone', 'addr','authordetail_info']
# 重写字段telephone和addr
telephone = serializers.CharField(write_only=True)
addr = serializers.CharField(write_only=True,max_length=8,required=False)
# 重写create，操作两个表
def create(self, validated_data):
# 先存作者详情
authordetail = models.AuthorDetail.objects.create(telephone=validated_data.get('telephone'),addr=validated_data.get('addr'))
# 存作者表
author = models.Author.objects.create(author_detail=authordetail,name=validated_data.get('name'),age=validated_data.get('age'))
# 这样只返回author对象就行，直接存了两个表,返回反序列化的对象
return author
Postman自行测试，我测了测都能用，有问题望指正~
注意
如果实际项目中不需要操作数据库可以使用APIView，如果操作数据库那么推荐使用GenericAPIView
