Django Rest Framework-序列化

简单使用

开发我们的Web API的第一件事是为我们的Web API提供一种将代码片段实例序列化和反序列化为诸如json之类的表示形式的方式。我们可以通过声明与Django forms非常相似的序列化器（serializers）来实现。

models部分:

from django.db import models

# Create your models here.


class Book(models.Model):
    title=models.CharField(max_length=32)
    price=models.IntegerField()
    pub_date=models.DateField()
    publish=models.ForeignKey("Publish")
    authors=models.ManyToManyField("Author")
    def __str__(self):
        return self.title

class Publish(models.Model):
    name=models.CharField(max_length=32)
    email=models.EmailField()
    def __str__(self):
        return self.name

class Author(models.Model):
    name=models.CharField(max_length=32)
    age=models.IntegerField()
    def __str__(self):
        return self.name

views部分：

from rest_framework.views import APIView
from rest_framework.response import Response
from .models import *
from django.shortcuts import HttpResponse
from django.core import serializers


from 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():
            temp.append(author.name)
        return temp


class BookViewSet(APIView):

    def get(self,request,*args,**kwargs):
        book_list=Book.objects.all()
        # 序列化方式1:
        # from django.forms.models import model_to_dict
        # import json
        # data=[]
        # for obj in book_list:
        #     data.append(model_to_dict(obj))
        # print(data)
        # return HttpResponse("ok")

        # 序列化方式2:
        # data=serializers.serialize("json",book_list)
        # return HttpResponse(data)

        # 序列化方式3:
        bs=BookSerializers(book_list,many=True)
        return Response(bs.data)

ModelSerializer

class BookSerializers(serializers.ModelSerializer):
      class Meta:
          model=Book
          fields="__all__"
          depth=1

提交post请求

  def post(self,request,*args,**kwargs):
       
        bs=BookSerializers(data=request.data,many=False)
        if bs.is_valid():
            # print(bs.validated_data)
            bs.save()
            return Response(bs.data)
        else:
            return HttpResponse(bs.errors)

 验证：

class ValidateView(APIView):
    def post(self, request, *args, **kwargs):
        data = request.data
        vali_data = ValidateSer(data=data)
        if vali_data.is_valid():
            return HttpResponse('成功')
        print(vali_data.errors)
        return HttpResponse('ok')


# 自定义验证规则
class HeaderValidator(object):
    def __init__(self, base):
        self.base = str(base)
    # 验证失败返回的信息
    def __call__(self, value):
        if self.base not in value:
            message = 'This field must be %s.' % self.base
            raise serializers.ValidationError(message)
    # 局部hook 
    def set_context(self, serializer_field):
        """
        This hook is called by the serializer instance,
        prior to the validation call being made.
        """
        # 执行验证之前调用,serializer_fields是当前字段对象
        return None


class ValidateSer(serializers.Serializer):
    username = serializers.CharField(
        # min_length=3,
        validators=[HeaderValidator("xiao")],
        error_messages={
            "required": "不能为空"
        },
    )
    password = serializers.CharField(
        min_length=5,
        error_messages={
            "required": "不能为空"
        }
    )
    re_password = serializers.CharField(
        min_length=5,
        error_messages={
            "required": "不能为空"
        }
    )
    # 局部hook
    def validate_username(self, value):
        if not 'xiaoxia' in value:
            raise serializers.ValidationError('就看你不顺眼', code=1000)
        return value
    # 全局hook
    def validate(self, value):
        password = value['password']
        re_password = value['re_password']
        if password != re_password:
            error = [{"password": '两次密码不一致'}]
            raise serializers.ValidationError(error[0])
        return value



    

重写save中的create方法

class BookSerializers(serializers.ModelSerializer):

      class Meta:
          model=Book
          fields="__all__"
          # exclude = ['authors',]
          # depth=1

      def create(self, validated_data):
        
          authors = validated_data.pop('authors')
          obj = Book.objects.create(**validated_data)
          obj.authors.add(*authors)
          return obj

 

 单条数据的get和put请求

class BookDetailViewSet(APIView):

    def get(self,request,pk):
        book_obj=Book.objects.filter(pk=pk).first()
        bs=BookSerializers(book_obj)
        return Response(bs.data)

    def put(self,request,pk):
        book_obj=Book.objects.filter(pk=pk).first()
        bs=BookSerializers(book_obj,data=request.data)
        if bs.is_valid():
            bs.save()
            return Response(bs.data)
        else:
            return HttpResponse(bs.errors)

 

超链接API：Hyperlinked

class BookSerializers(serializers.ModelSerializer):
      publish= serializers.HyperlinkedIdentityField(
                     view_name='publish_detail',
                     lookup_field="publish_id",
                     lookup_url_kwarg="pk")
      class Meta:
          model=Book
          fields="__all__"
          #depth=1

 

urls部分：

urlpatterns = [
    url(r'^books/$', views.BookViewSet.as_view(),name="book_list"),
    url(r'^books/(?P<pk>\d+)$', views.BookDetailViewSet.as_view(),name="book_detail"),
    url(r'^publishers/$', views.PublishViewSet.as_view(),name="publish_list"),
    url(r'^publishers/(?P<pk>\d+)$', views.PublishDetailViewSet.as_view(),name="publish_detail"),
]