Django REST framework 中的序列化器

在此之前定义一个序列化工具：

views中的的代码

from rest_framework.viewsets import ModelViewSet

from .models import BookInfo

from .serializers import BookInfoSerializers

class BookInfoViewSet(ModelViewSet):

    queryset = BookInfo.objects.all() # 取序列化模型

    serializer_class = BookInfoSerializers # 指定序列化的类

定制url

from django.conf.urls import url, include

from . import views

from rest_framework.routers import DefaultRouter

router = DefaultRouter()

router.register(r"books", views.BookInfoViewSet)

urlpatterns = [

    url(r'^index/$', views.index),

]

urlpatterns += router.urls

访问路径配置

http://127.0.0.1:8000/app001/books/

定制普通的序列化类

已有的model数据类型如下所示：

class BookInfo(models.Model):

    btitle = models.CharField(max_length=20, verbose_name='名称')

    bpub_date = models.DateField(verbose_name='发布日期')

    bread = models.IntegerField(default=0, verbose_name='阅读量')

    bcomment = models.IntegerField(default=0, verbose_name='评论量')

    is_delete = models.BooleanField(default=False, verbose_name='逻辑删除')

    class Meta:

        db_table = 'tb_books'  # 指明数据库表名

        verbose_name = '图书'  # 在admin站点中显示的名称

        verbose_name_plural = verbose_name  # 显示的复数名称

    def __str__(self):

        return self.btitle

继承serializers.Serializer的序列化器：

# 为以上的model定制一个序列化器

from rest_framework import serializers

class BookInfoSerializers(serializers.Serializer):

    """ 图书列表序列化器"""

    id = serializers.IntegerField(label="ID", read_only=True)

    btitle = serializers.CharField(label="名称", max_length=20)

    bpub_date = serializers.DateField(label='发布日期', required=False)

    bread = serializers.IntegerField(label='阅读量', required=False)

    bcomment = serializers.IntegerField(label='评论量', required=False)

    is_delete = serializers.BooleanField(label='逻辑删除', required=False)

演示效果（python manages.py shell的环境下运行）：

# 查询图书的的对象

from app001.models import BookInfo

book = BookInfo.objects.all()[0]

# 构造序列化器

from app001.serializers import BookInfoSerializers

serializer = BookInfoSerializers(book)

# 获取序列化之后的属性

print(serializer.data)

 
# 打印效果：

"""

{'id': 1, 'bpub_date': '1980-05-01', 'btitle': '射雕英雄传', 'is_delete': False, 'bcomment': 34, 'bread': 12}

"""

model类

class HeroInfo(models.Model):

    GENDER_CHOICES = (

        (0, 'male'),

        (1, 'female')

    )

    hname = models.CharField(max_length=20, verbose_name='名称')

    hgender = models.SmallIntegerField(choices=GENDER_CHOICES, default=0, verbose_name='性别')

    hcomment = models.CharField(max_length=200, null=True, verbose_name='描述信息')

    hbook = models.ForeignKey(BookInfo, on_delete=models.CASCADE, verbose_name='图书')  # 外键

    is_delete = models.BooleanField(default=False, verbose_name='逻辑删除')

    class Meta:

        db_table = 'tb_heros'

        verbose_name = '英雄'

        verbose_name_plural = verbose_name

    def __str__(self):

        return self.hname

序列化器

from rest_framework import serializers

class HeroInfoSerializers(serializers.Serializer):

    """英雄数据序列化器"""

    GENDER_CHOICES = (

        (0, 'male'),

        (1, 'female')

    )

    # hname = models.CharField(max_length=20, verbose_name='名称')

    id = serializers.IntegerField(label='ID', read_only=True)

    # hgender = models.SmallIntegerField(choices=GENDER_CHOICES, default=0, verbose_name='性别')

    hgender = serializers.ChoiceField(choices=GENDER_CHOICES, label='性别', required=False)

    # hcomment = models.CharField(max_length=200, null=True, verbose_name='描述信息')

    hcomment = serializers.CharField(label='描述信息', max_length=200, required=False, allow_null=True)

    # hbook = models.ForeignKey(BookInfo, on_delete=models.CASCADE, verbose_name='图书')  # 外键

    hbook = serializers.PrimaryKeyRelatedField(label='图书', read_only=True)

    # is_delete = models.BooleanField(default=False, verbose_name='逻辑删除')

交互界面输出

# 查询英雄的对象

from app001.models import HeroInfo

hero = HeroInfo.objects.all()[0]

from app001.serializers import HeroInfoSerializers

hs = HeroInfoSerializers(hero)

print(hs.data)

"""

{'hgender': 1, 'id': 1, 'hcomment': '降龙掌', 'hbook': '射雕英雄传'}

{'hgender': 1, 'id': 1, 'hcomment': '降龙掌', 'hbook': 1}

"""

此字段将被序列化为关联对象的主键。

（hbook = serializers.PrimaryKeyRelatedField(label='图书', read_only=True)

hbook = serializers.PrimaryKeyRelatedField(label='图书',queryset=BookInfo.objects.all())）

print(hs.data)

"""

{'hgender': 1, 'id': 1, 'hcomment': '降龙掌', 'hbook': 1}

"""

（hbook = serializers.StringRelatedField(label='图书')）

print(hs.data)

"""

{'hgender': 1, 'id': 1, 'hcomment': '降龙掌', 'hbook': '射雕英雄传'}

"""

（ hbook = serializers.SlugRelatedField(label='图书', read_only=True, slug_field='bpub_date')

）

{'hbook': datetime.date(1980, 5, 1), 'hcomment': '降龙掌', 'hgender': 1, 'id': 1}

（ hbook = BookInfoSerializers()

）

{'hgender': 1, 'hcomment': '降龙掌', 'id': 1, 'hbook': OrderedDict([('id', 1), ('btitle', '射雕英雄传'), ('bpub_date', '1980-05-01'), ('bread', 12), ('bcomment', 34), ('is_delete', False)])}

（ hbook = BookRelateField(read_only="True")）

{'hcomment': '降龙掌', 'hbook': 'Book: 1 射雕英雄传', 'id': 1, 'hgender': 1}

（ heroinfo_set = serializers.PrimaryKeyRelatedField(read_only=True, many=True) # 新增

）

测试命令

from app001.models import BookInfo

book = BookInfo.objects.all()[0]

# 构造序列化器

from app001.serializers import BookInfoSerializers

bs = BookInfoSerializers(book)

# 获取序列化之后的属性

print(bs.data)

{'bread': 12, 'is_delete': False, 'bpub_date': '1980-05-01', 'heroinfo_set': [1, 2, 3, 4, 5], 'btitle': '射雕英雄传', 'id': 1, 'bcomment': 34}

from app001.serializers import BookInfoSerializers

data = {'bpub_date': 123}

serializer = BookInfoSerializers(data=data)

serializer.is_valid()

serializer.errors

serializer.validated_data

from app001.serializers import BookInfoSerializers

data = {'bpub_date': "1993-12-27", 'btitle': 'python'}

serializer = BookInfoSerializers(data=data)

serializer.is_valid()

serializer.errors

serializer.validated_data

"""

OrderedDict([('btitle', 'python'), ('bpub_date', datetime.date(1993, 12, 27))])

"""

验证失败报404异常

serializer.is_valid(raise_exception=True)

from rest_framework import serializers

class BookInfoSerializers(serializers.Serializer):

    """ 图书列表序列化器"""

    id = serializers.IntegerField(label="ID", read_only=True)

    btitle = serializers.CharField(label="名称", max_length=20)

    bpub_date = serializers.DateField(label='发布日期', required=False)

    bread = serializers.IntegerField(label='阅读量', required=False)

    bcomment = serializers.IntegerField(label='评论量', required=False)

    is_delete = serializers.BooleanField(label='逻辑删除', required=False)

    heroinfo_set = serializers.PrimaryKeyRelatedField(read_only=True, many=True)  # 新增

    def validate_btitle(self, value):

        if 'django' not in value.lower():

            raise serializers.ValidationError("图书不是关于Django的")

        return value

from app001.serializers import BookInfoSerializers

data = {'bpub_date': "1993-12-27", 'btitle': 'python_django'}

serializer = BookInfoSerializers(data=data)

serializer.is_valid()

serializer.errors

serializer.validated_data

"""

OrderedDict([('btitle', 'python_django'), ('bpub_date', datetime.date(1993, 12, 27))])

"""

在序列化器中定义一个validate（）在这个方法中定义的字段会在最后被验证；

from rest_framework import serializers

def about_django(value):

    if 'django' not in value.lower():

        raise serializers.ValidationError("about_django中抛出图书不是关于Django的")

class BookInfoSerializers(serializers.Serializer):

    """ 图书列表序列化器"""

    id = serializers.IntegerField(label="ID", read_only=True)

    btitle = serializers.CharField(label="名称", max_length=20,validators=[about_django])

    bpub_date = serializers.DateField(label='发布日期', required=False)

    bread = serializers.IntegerField(label='阅读量', required=False)

    bcomment = serializers.IntegerField(label='评论量', required=False)

    is_delete = serializers.BooleanField(label='逻辑删除', required=False)

    heroinfo_set = serializers.PrimaryKeyRelatedField(read_only=True, many=True)  # 新增

    def validate(self, attrs):

        bread = attrs['bread']

        bcomment = attrs['bcomment']

        if bread < bcomment:

            raise serializers.ValidationError('阅读量小于评论量')

        return attrs

>>> from app001.serializers import BookInfoSerializers

>>> data = {'bcomment': 34, 'bread': 12,'bpub_date': "1993-12-27", 'btitle': 'python_django'}

>>> serializer = BookInfoSerializers(data=data)

>>> serializer.is_valid()

False

>>> serializer.errors

{'non_field_errors': [ErrorDetail(string='阅读量小于评论量', code='invalid')]}

>>> serializer.validated_data

{}

抛出异常：

>>> from app001.serializers import BookInfoSerializers

>>> data = {'bcomment': 14, 'bread': 12,'bpub_date': "1993-12-27", 'btitle': 'ptython'}

>>> serializer = BookInfoSerializers(data=data)

>>> serializer.is_valid()

False

>>> serializer.errors

{'btitle': [ErrorDetail(string='about_django中抛出图书不是关于Django的', code='invalid')]}

>>> serializer.validated_data

{}

>>>

在序列化器类的内部定义一个方法，来验证字段的属性（注意定义的函数的结构）；

from rest_framework import serializers

class BookInfoSerializers(serializers.Serializer):

    """ 图书列表序列化器"""

    id = serializers.IntegerField(label="ID", read_only=True)

    btitle = serializers.CharField(label="名称", max_length=20,validators=[about_django])

    bpub_date = serializers.DateField(label='发布日期', required=False)

    bread = serializers.IntegerField(label='阅读量', required=False)

    bcomment = serializers.IntegerField(label='评论量', required=False)

    is_delete = serializers.BooleanField(label='逻辑删除', required=False)

    heroinfo_set = serializers.PrimaryKeyRelatedField(read_only=True, many=True)  # 新增

    def validate_btitle(self, value):

        if 'django' not in value.lower():

            raise serializers.ValidationError("图书不是关于Django的")

        return value

验证成功：

>>> from app001.serializers import BookInfoSerializers

>>> data = {'bcomment': 10, 'bread': 12,'bpub_date': "1993-12-27", 'btitle': 'python_django'}

>>> serializer = BookInfoSerializers(data=data)

>>> serializer.is_valid()

True

>>> serializer.errors

{}

>>> serializer.validated_data

OrderedDict([('btitle', 'python_django'), ('bpub_date', datetime.date(1993, 12, 27)), ('bread', 12), ('bcomment', 10)])

>>>

验证失败：

>>> from app001.serializers import BookInfoSerializers

>>> data = {'bcomment': 10, 'bread': 12,'bpub_date': "1993-12-27", 'btitle': 'ptython'}

>>> serializer = BookInfoSerializers(data=data)

>>> serializer.is_valid()

False

>>> serializer.errors

{'btitle': [ErrorDetail(string='图书不是关于Django的', code='invalid')]}

>>> serializer.validated_data

{}

在序列化器的外部定义一个方法，将该方法加入到字段中作为字段的验证方法

from rest_framework import serializers

def about_django(value):

    if 'django' not in value.lower():

        raise serializers.ValidationError("图书不是关于Django的")

class BookInfoSerializers(serializers.Serializer):

    """ 图书列表序列化器"""

    id = serializers.IntegerField(label="ID", read_only=True)

    btitle = serializers.CharField(label="名称", max_length=20,validators=[about_django])

    bpub_date = serializers.DateField(label='发布日期', required=False)

    bread = serializers.IntegerField(label='阅读量', required=False)

    bcomment = serializers.IntegerField(label='评论量', required=False)

    is_delete = serializers.BooleanField(label='逻辑删除', required=False)

    heroinfo_set = serializers.PrimaryKeyRelatedField(read_only=True, many=True)  # 新增

    def validate_btitle(self, value):

        if 'django' not in value.lower():

            raise serializers.ValidationError("图书不是关于Django的")

        return value

    def validate(self, attrs):

        bread = attrs['bread']

        bcomment = attrs['bcomment']

        if bread < bcomment:

            raise serializers.ValidationError('阅读量小于评论量')

        return attrs

返回成功：

>>> from app001.serializers import BookInfoSerializers

>>> data = {'bcomment': 10, 'bread': 12,'bpub_date': "1993-12-27", 'btitle': 'ptython_django'}

>>> serializer = BookInfoSerializers(data=data)

>>> serializer.is_valid()

True

>>> serializer.errors

{}

>>> serializer.validated_data

OrderedDict([('btitle', 'ptython_django'), ('bpub_date', datetime.date(1993, 12, 27)), ('bread', 12), ('bcomment', 10)])

返回失败：

>>> from app001.serializers import BookInfoSerializers

>>> data = {'bcomment': 10, 'bread': 12,'bpub_date': "1993-12-27", 'btitle': 'ptython'}

>>> serializer = BookInfoSerializers(data=data)

>>> serializer.is_valid()

False

>>> serializer.errors

{'btitle': [ErrorDetail(string='about_django中抛出图书不是关于Django的', code='invalid')]}

>>> serializer.validated_data

{}

验证顺序：

1，model字段本身;

2，字段中定义的validators;

3,序列化器中定义的对字段的验证方法validate_字段名；

4, 序列话器中validate的方法。

单字段唯一；

from rest_framework.validators import UniqueValidator

slug = SlugField(

    max_length=100,

    validators=[UniqueValidator(queryset=BlogPost.objects.all())]

)

联合唯一；

from rest_framework.validators import UniqueTogetherValidator

class ExampleSerializer(serializers.Serializer):

# ...

class Meta:

validators = [

UniqueTogetherValidator(

queryset=ToDoItem.objects.all(),

fields=('list', 'position')

)

]

序列化后的数据保存

验证未通过程序包报错：

>>> from app001.serializers import BookInfoSerializers

>>> data = {'btitle': '封神演义'}

>>> serializer = BookInfoSerializers(data=data)

>>> serializer.is_valid()

False

>>> serializer.save()

Traceback (most recent call last):

  File "<console>", line 1, in <module>

  File "/home/python/.virtualenvs/djf/lib/python3.5/site-packages/rest_framework/serializers.py", line 184, in save

    'You cannot call `.save()` on a serializer with invalid data.'

AssertionError: You cannot call `.save()` on a serializer with invalid data.

验证通过并保存

>>> from app001.serializers import BookInfoSerializers

>>> data = {'bcomment': 10, 'bread': 12,'bpub_date': "1993-12-27", 'btitle': 'ptython_django'}

>>> serializer = BookInfoSerializers(data=data)

>>> serializer.is_valid()

True

>>> serializer.save()

<BookInfo: ptython_django>

序列化器的定义

from rest_framework import serializers

def about_django(value):

    if 'django' not in value.lower():

        raise serializers.ValidationError("about_django中抛出图书不是关于Django的")

class BookInfoSerializers(serializers.Serializer):

    """ 图书列表序列化器"""

    id = serializers.IntegerField(label="ID", read_only=True)

    btitle = serializers.CharField(label="名称", max_length=20, validators=[about_django])

    bpub_date = serializers.DateField(label='发布日期', required=False)

    bread = serializers.IntegerField(label='阅读量', required=False)

    bcomment = serializers.IntegerField(label='评论量', required=False)

    is_delete = serializers.BooleanField(label='逻辑删除', required=False)

    heroinfo_set = serializers.PrimaryKeyRelatedField(read_only=True, many=True)  # 新增

    def validate_btitle(self, value):

        if 'django' not in value.lower():

            raise serializers.ValidationError("图书不是关于Django的")

        return value

    def create(self, validated_data):

        """新建"""

        return BookInfo.objects.create(**validated_data)

    def update(self, instance, validated_data):

        """更新，instance为要更新的对象实例"""

        instance.btitle = validated_data.get('btitle', instance.btitle)

        instance.bpub_date = validated_data.get('bpub_date', instance.bpub_date)

        instance.bread = validated_data.get('bread', instance.bread)

        instance.bcomment = validated_data.get('bcomment', instance.bcomment)

        instance.save()

        return instance

成功创建对象

>>> from app001.serializers import BookInfoSerializers

>>> # from app001.models import BookInfo

>>> # book = BookInfo.objects.filter(btitle="ptython_django")[0]

>>> book = BookInfo.objects.get(id=10)

>>> data = {'bcomment': 10, 'bread': 12,'bpub_date': "1994-12-27", 'btitle': 'ptython_django'}

>>> # data = {'bpub_date': "1994-12-27",'bcomment': 10, 'bread': 12,}

>>> serializer = BookInfoSerializers(book, data=data)

>>> serializer.is_valid()

True

>>> serializer.save()

<BookInfo: ptython_django>

>>> book.btitle

'ptython_django'

>>>

成功修改对象传入对象中的属性；

>>> from app001.serializers import BookInfoSerializers

>>> from app001.models import BookInfo

>>> book = BookInfo.objects.filter(btitle="ptython_django")[0]

>>> data = {'bcomment': 10, 'bread': 12,'bpub_date': "1995-12-27", 'btitle': 'ptython_django'}

>>> serializer = BookInfoSerializers(book, data=data)

>>> serializer.is_valid()

True

>>> serializer.save()

<BookInfo: ptython_django>

>>> book.btitle

'ptython_django'

>>> book.bpub_date

datetime.date(1995, 12, 27)

修改通过书名取到的的对象的值；

>>> from app001.serializers import BookInfoSerializers

>>> from app001.models import BookInfo

>>> book = BookInfo.objects.filter(btitle="ptython_django")[0]

>>> data = {'bpub_date': "1996-12-27", 'btitle': 'ptython_django'}

>>> serializer = BookInfoSerializers(book, data=data)

>>> serializer.is_valid()

True

>>> serializer.save()

<BookInfo: ptython_django>

>>> book.btitle

'ptython_django'

>>> book.bpub_date

datetime.date(1996, 12, 27)

Django REST framework 中的序列化器的更多相关文章

DRF中的序列化器
DRF中的序列化器详细应用视图的功能:说白了就是接收前端请求,进行数据处理 (这里的处理包括:如果前端是GET请求,则构造查询集,将结果返回,这个过程为序列化:如果前端是POST请求,假如要对数 ...
Python的Django REST框架中的序列化及请求和返回
Python的Django REST框架中的序列化及请求和返回序列化Serialization 1. 设置一个新的环境在我们开始之前, 我们首先使用virtualenv要创建一个新的虚拟环境,以使 ...
Django REST framework 中文文档
Django REST framework介绍现在前后端分离的架构设计越来越流行,业界甚至出现了API优先的趋势. 显然API开发已经成为后端程序员的必备技能了,那作为Python程序员特别是把Dj ...
Django REST framework 中的视图
1.Request REST framework传入视图的request对象不再是Django默认的Httprequest对象,而是DRF提供的扩展类的Request类的对象常用属性 request ...
DRF (Django REST framework) 中的视图类
视图说明 1. 两个基类 1)APIView rest_framework.views.APIView APIView是REST framework提供的所有视图的基类,继承自Django的View父 ...
DRF (Django REST framework) 中的Request 与 Response
DRF中的Request 与 Response 1. Request - REST framework 传入视图的request对象不再是Django默认的HttpRequest对象,而是REST f ...
在django restful framework中设置django model的property
众所周知,在django的model中,可以某些字段设置@property和setter deleter getter,这样就可以在存入数据的时候进行一些操作,具体原理请参见廖雪峰大神的博客https ...
Django：（08）序列化器
1.序列化和反序列化变量从内存中变成可存储或传输的过程称之为序列化,序列化之后,就可以把序列化后的内容写入磁盘,或者通过网络传输到别的机器上.反过来,把变量内容从序列化的对象重新读到内存里称之为反序列 ...
Django REST framework中的版本控制
1.REST framework版本控制的流程分析 1.1 determine_version方法的执行流程首先,请求到达REST framework的CBV,执行CBV中的dispatch方法再次 ...

随机推荐

Can't connect to X11 window server using 的问题，求解
在JVM中加入-Djava.awt.headless=true对于tomcat ,可以修改catalina.sh,加入:CATALINA_OPTS="$CATALINA_OPTS -Djav ...
thinkphp5分页传参
$name = input('get.searchKey/s'); if($name != ""){ $this->assign('searchKey', $name); $ ...
数据库vertica 脚本方式的导入导出
需要进入vsql下的: 导入: copy emp from '/tmp/emp.csv' DELIMITER ',' ESCAPE AS '\' ENCLOSED BY '"' DIRECT ...
POJ 2987 Firing【最大权闭合图-最小割】
题意:给出一个有向图,选择一个点,则要选择它的可以到达的所有节点.选择每个点有各自的利益或损失.求最大化的利益,以及此时选择人数的最小值. 算法:构造源点s汇点t,从s到每个正数点建边,容量为利益.每 ...
2n的位数
len=())+,(2n−1同样适用)
Windows 下安装 Ubuntu 双系统(更新)
Windows + Ubuntu 16.04 ---> 双系统前言:本篇文章是对之前文章的更新,更新的主内容是把原来用手机拍摄的图片换成了虚拟机的截图,以及对磁盘划分的新的见解和一些使用感受, ...
20165235 实验一 Java开发环境的熟悉
20165235 实验一 Java开发环境的熟悉课程:JAVA程序设计姓名:祁瑛学号:20165235 指导老师:娄嘉鹏实验日期: 2018.4.2 实验内容:java开发环境的熟悉一,实验 ...
Kafka生产者案例报警告SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
一.SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder". 这个报警告的原因简单来说时因为slf4j的版本 ...
Why Did the Cow Cross the Road III HYSBZ - 4991 -CDQ-逆序数
HYSBZ - 4991 题意: 第一列 1-n的排列 ,第二列 1-n的排列. 相同数字连边 ,问有多少组数字是有交点的并且绝对值之差>K思路:处理一下 1-n 在第一列的位置, ...
P3812 【模板】线性基
P3812 [模板]线性基理解 :线性基类似于向量的极大无关组,就是保持原来所有数的异或值的最小集合, 求解过程也类似,可以 O( 60 * n )的复杂度求出线性基,线性基有许多性质,例如线 ...

Django REST framework 中的序列化器

Django REST framework 中的序列化器的更多相关文章

随机推荐

热门专题