day72_10_17 序列化组件之model的运用

一。拆分的序列化。

  model序列化的基本用法就是使用元类中的fields,其中model绑定的就是model中的表

  如果需要多表查询,要在model中定义property:

class BookModelSerializer(ModelSerializer):
    publish = PublishModelSerializer()

    class Meta:
        model = models.Book
        fields = ('name', 'price', 'img', 'author_list', 'publish')

  model该表中的property方法:

    @property
    def publish_name(self):
        return self.publish.name

    @property
    def author_list(self):
        return self.authors.values('name', 'age','detail__mobile').all()

  这些都是model中的字段。

  第二种就是使用外接的序列化类生成序列化对象,然后作为字段添加到field中。这种设定不是可插拔式的。

class PublishModelSerializer(ModelSerializer):
    class Meta:
        model = models.Publish
        fields = ('name', 'address')

class BookModelSerializer(ModelSerializer):

    publish = PublishModelSerializer()

    class Meta:
        model = models.Book
        fields = ('name', 'price', 'img', 'author_list', 'publish')

  第三种不常用,就是使用field。exclude除了这立马的字段之外其他都显示,另加depth作为深度。

class BookModelSerializer(ModelSerializer):
    publish = PublishModelSerializer()
    class Meta:
        model = models.Book
        fields = ('name', 'price', 'img', 'author_list', 'publish')
        # 了解知识点
        # 所有字段
        # fields = '__all__'
        # 与fields不共存,exclude排除哪些字段
        # exclude = ('id', 'is_delete', 'create_time')
        # 自动连表深度
        # depth = 1

  这些序列化类在被定义之后,在view视图层种调用,调用的参数有instance,date和many

  instance是需要序列化的对象,date是从前端接受的数据,many就是是否为多单位。

class Book(APIView):
    def get(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:
            try:
                book_obj = models.Book.objects.get(pk=pk, is_delete=False)
                book_data = serializers.BookModelSerializer(book_obj).data
            except:
                return Response({
                    'status': 1,
                    'msg': '书籍不存在'
                })
        else:
            book_query = models.Book.objects.filter(is_delete=False).all()
            book_data = serializers.BookModelSerializer(book_query, many=True).data
        return Response({
            'status': 0,
            'msg': 'ok',
            'results': book_data
        })
view

  反序列化使用:

  重新继承一个modelserializer类,反序列化需要使用元类字段extra_kwargs。

  这个是其他关键字段,其中的元素就是fields种的字段,字段种使用字段进行判断:

  required:是否必填。

  min_length等长度提示,

  error_messages则是以上限时生效的时候返回给前端的错误信息。

  进行反序列化后可以通过钩子函数(局部和全局)进判断。

class BookModelDeserializer(ModelSerializer):
    class Meta:
        model = models.Book
        fields = ('name', 'price', 'publish', 'authors')
        # extra_kwargs 用来完成反序列化字段的 系统校验规则
        extra_kwargs = {
            'name': {
                'required': True,
                'min_length': 1,
                'error_messages': {
                    'required': '必填项',
                    'min_length': '太短',
                }
            }
        }
    
    # 局部钩子
    def validate_name(self, value):
        # 书名不能包含 g 字符
        if 'g' in value.lower():
            raise ValidationError('该g书不能出版')
        return value
    # 全局钩子
    def validate(self, attrs):
        publish = attrs.get('publish')
        name = attrs.get('name')
        if models.Book.objects.filter(name=name, publish=publish):
            raise ValidationError({'book': '该书已存在'})
        return attrs

    # ModelSerializer类已经帮我们实现了 create 与 update 方法
serializers

  这个模块已经帮我们实现了create和update,只需要在前端调用save方法即可。

二。整合的序列化。

  在序列化类中,有以下信息:

  model = models.book  模块的定义

  fields = 操作的字段定义。

  extra_kwargs  对字段的操作

  在对字段的操作中,有三选一的操作:

    required:True  是否必填。

    read_only  只能序列化。

    write_only 只能反序列化。

"""
1) fields中设置所有序列化与反序列化字段
2) extra_kwargs划分只序列化或只反序列化字段
    write_only:只反序列化
    read_only:只序列化
    自定义字段默认只序列化(read_only)
3) 设置反序列化所需的 系统、局部钩子、全局钩子 等校验规则
"""
class V2BookModelSerializer(ModelSerializer):
    class Meta:
        model = models.Book
        fields = ('name', 'price', 'img', 'author_list', 'publish_name', 'publish', 'authors')
        extra_kwargs = {
            'name': {
                'required': True,
                'min_length': 1,
                'error_messages': {
                    'required': '必填项',
                    'min_length': '太短',
                }
            },
            'publish': {
                'write_only': True
            },
            'authors': {
                'write_only': True
            },
            'img': {
                'read_only': True,
            },
            'author_list': {
                'read_only': True,
            },
            'publish_name': {
                'read_only': True,
            }
        }

    def validate_name(self, value):
        # 书名不能包含 g 字符
        if 'g' in value.lower():
            raise ValidationError('该g书不能出版')
        return value

    def validate(self, attrs):
        publish = attrs.get('publish')
        name = attrs.get('name')
        if models.Book.objects.filter(name=name, publish=publish):
            raise ValidationError({'book': '该书已存在'})
        return attrs
整合的序列化

三。单查询和群查询。

  主要通过路由传输参数pk,判断是否有pk如果有pk则为单查,如果没有pk则为群查。

'''
单查路由:http://127.0.0.1:8000/api/v2/books/1/
单查数据返回:{
    "status": 0,
    "msg": "ok",
    "results": {
        "name": "南开大学",
        "price": "12.00",
        "img": "/media/img/default.jpg",
        "publish_name": "东京出版社",
    }
}
群查路由:http://127.0.0.1:8000/api/v2/books
群查数据返回:{
    "status": 0,
    "msg": "ok",
    "results": [
        {
            "name": "南开大学",
            "price": "12.00",
            "img": "/media/img/default.jpg",
            "publish_name": "东京出版社",
            "author_list": [
                {
                    "id": 1,
                    "is_delete": false,
                    "create_time": "2019-10-17T11:09:29.316398",
                    "name": "zzj",
                    "age": 12
                },
                {
                    "id": 2,
                    "is_delete": false,
                    "create_time": "2019-10-17T11:10:21.914888",
                    "name": "zzp",
                    "age": 43
                }
            ]
        },
        {
            "name": "南开大学",
            "price": "12.00",
            "img": "/media/img/default.jpg",
            "publish_name": "东京出版社",
            "author_list": [
                {
                    "id": 1,
                    "is_delete": false,
                    "create_time": "2019-10-17T11:09:29.316398",
                    "name": "zzj",
                    "age": 12
                },
                {
                    "id": 2,
                    "is_delete": false,
                    "create_time": "2019-10-17T11:10:21.914888",
                    "name": "zzp",
                    "age": 43
                }
            ]
        }
]
}
'''
def get(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:
            try:
                book_obj = models.Book.objects.get(pk=pk, is_delete=False)
                book_data = serializers.V2BookModelSerializer(book_obj).data
            except:
                return Response({
                    'status': 1,
                    'msg': '书籍不存在'
                })
        else:
            book_query = models.Book.objects.filter(is_delete=False).all()
            book_data = serializers.V2BookModelSerializer
          (book_query, many=True).data return Response({ 'status': 0, 'msg': 'ok', 'results': book_data })

四,单增和多增。

  增加的逻辑就是判断传入的数据是否是字典或列表,是字典则是单个,列表则是多个

'''
增添路由:http://127.0.0.1:8000/api/v2/books/
单增输入:
{
    "name":"南开大学12",
    "price":12,
    "publish":1,
    "authors":[1,2]
}
多增输入:
[
{
    "name":"南开大学1",
    "price":12,
    "publish":1,
    "authors":[1,2]
},
{
    "name":"南开大学2",
    "price":12,
    "publish":1,
    "authors":[1,2]
}
]
数据返回:
{
    "status": 0,
    "msg": "ok",
    "results": {
        "name": "南开大学12",
        "price": "12.00",
        "img": "/media/img/default.jpg",
        "publish_name": "东京出版社",
    }
}
'''

    def post(self, request, *args, **kwargs):
        request_data = request.data
        if isinstance(request_data, dict):
            many = False
        elif isinstance(request_data, list):
            many = True
        else:
            return Response({
                'status': 1,
                'msg': '数据有误',
            })
        book_ser = serializers.V2BookModelSerializer
        (data=request_data, many=many) # 当校验失败,马上终止当前视图方法,抛异常返回给前台 book_ser.is_valid(raise_exception=True) book_result = book_ser.save() return Response({ 'status': 0, 'msg': 'ok', 'results': serializers.V2BookModelSerializer
                (book_result, many=many).data })

五。单删和多删。

  单次删除时添加参数pk,而如果没有pk,则会获取传入参数 的数据中的pks。

  最后都生成列表以并操作。

'''
单删路由:http://127.0.0.1:8000/api/v2/books/7/
多删路由:http://127.0.0.1:8000/api/v2/books/
多删输入:{"pks": [1, 2, 3]}
返回数据{
    "status": 0,
    "msg": "删除成功"
}
'''
    def delete(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:
            pks = [pk]
        else:
            pks = request.data.get('pks')
        if models.Book.objects.filter(pk__in=pks, is_delete=False).update
          (is_delete=True): return Response({ 'status': 0, 'msg': '删除成功', }) return Response({ 'status': 1, 'msg': '删除失败', })

六。整体单改

  修改主要取决于序列化对象中的参数partial和所有字段中的required对象

"""
1) 单整体改,说明前台要提供修改的数据,那么数据就需要校验,
  校验的数据应该在实例化“序列化类对象”时,赋值给data 2)修改,就必须明确被修改的模型类对象,并在实例化“序列化类对象”时,赋值给instance 3)整体修改,所有校验规则有required=True的字段,都必须提供,因为在实例化“序列化类对象”时,
  参数partial默认为False 注:如果partial值设置为True,就是可以局部改 1)单整体修改,一般用put请求: V2BookModelSerializer( instance=要被更新的对象, data=用来更新的数据, partial=默认False,必须的字段全部参与校验 ) 2)单局部修改,一般用patch请求: V2BookModelSerializer( instance=要被更新的对象, data=用来更新的数据, partial=设置True,必须的字段都变为选填字段 ) 注:partial设置True的本质就是使字段 required=True 校验规则失效
"""

  对于单体全修改,使用put来提交数据。

  如果系列化对象中同时存在对象和数据时,就会修改该数据:

'''
修改路由:http://127.0.0.1:8000/api/v2/books/7/
修改输入:
{
    "name":"南开大学123",
    "price":12,
    "publish":1,
    "authors":[1,2]
}(所有必填字段都要)
'''
class V2Book(APIView):
    # 单整体改: 对 v2/books/(pk)/ 传的数据是与model对应的字典
    {name|price|publish|authors}
def put(self, request, *args, **kwargs): request_data = request.data pk = kwargs.get('pk') old_book_obj = models.Book.objects.filter(pk=pk).first() # 目的:将众多数据的校验交给序列化类来处理 - 让序列化类扮演反序列化角色,
        校验成功后,序列化类来帮你入库
book_ser = serializers.V2BookModelSerializer(instance=old_book_obj,
          data=request_data, partial=False) book_ser.is_valid(raise_exception=True) # 校验通过,完成数据的更新:要更新的目标,用来更新的新数据 book_obj = book_ser.save() return Response({ 'status': 0, 'msg': 'ok', 'results': serializers.V2BookModelSerializer(book_obj).data })

七。单改和群局部修改。

  只需要修改被改的对象。

  首先通过是否有pk和传入的修改数据对象类型进行判断,同一替换成列表。

  群体修改的数据需要一一对应。然后弹出pk。

  其中需要定义listserializer中的update方法,重写,可以调用子的update方法进行重写。

# 重点:ListSerializer与ModelSerializer建立关联的是:
# ModelSerializer的Meta类的 - list_serializer_class
class V2BookListSerializer(ListSerializer):
    def update(self, instance, validated_data):
        # print(instance)  # 要更新的对象们
        # print(validated_data)  # 更新的对象对应的数据们
        # print(self.child)  # 服务的模型序列化类 - V2BookModelSerializer
        for index, obj in enumerate(instance):
            self.child.update(obj, validated_data[index])
        return instance
    
# 原模型序列化类变化
class V2BookModelSerializer(ModelSerializer):
    class Meta:
        # ...
        # 群改,需要设置 自定义ListSerializer,重写群改的 update 方法
        list_serializer_class = V2BookListSerializer
    # ...

  视图:

'''
单局部修改路由:http://127.0.0.1:8000/api/v2/books/7/
单局部修改输入:{"name":"南开大学1234"}
群局部修改路由:http://127.0.0.1:8000/api/v2/books/
群局部修改输入:[
{"pk":1, "name":"123"}, 
{"pk":3, "price":7}, 
{"pk":7, "publish":2}
]

'''
class V2Book(APIView):
    # 单局部改:对 v2/books/(pk)/ 传的数据,数据字段key都是选填
    # 群局部改:对 v2/books/ 
    # 请求数据 - [{pk:1, name:123}, {pk:3, price:7}, {pk:7, publish:2}]
    def patch(self, request, *args, **kwargs):
        request_data = request.data
        pk = kwargs.get('pk')

        # 将单改,群改的数据都格式化成 pks=[要需要的对象主键标识] | 
      request_data=[每个要修改的对象对应的修改数据]
if pk and isinstance(request_data, dict): # 单改 pks = [pk, ] request_data = [request_data, ] elif not pk and isinstance(request_data, list): # 群改 pks = [] for dic in request_data:
      # 遍历前台数据[{pk:1, name:123}, {pk:3, price:7}, {pk:7, publish:2}],
      拿一个个字典
pk = dic.pop('pk', None) if pk: pks.append(pk) else: return Response({ 'status': 1, 'msg': '数据有误', }) else: return Response({ 'status': 1, 'msg': '数据有误', }) # pks与request_data数据筛选, # 1)将pks中的没有对应数据的pk与数据已删除的pk移除,
       request_data对应索引位上的数据也移除
# 2)将合理的pks转换为 objs objs = [] new_request_data = [] # [{},{},{}] for index, pk in enumerate(pks): try: # pk对应的数据合理,将合理的对象存储 obj = models.Book.objects.get(pk=pk) objs.append(obj) # 对应索引的数据就需要保存下来 new_request_data.append(request_data[index]) except: # 重点:反面教程 - pk对应的数据有误,
          将对应索引的data中request_data中移除
# index = pks.index(pk) # request_data.pop(index) continue book_ser = serializers.V2BookModelSerializer
      (instance=objs, data=new_request_data, partial=True, many=True) book_ser.is_valid(raise_exception=True) book_objs = book_ser.save() return Response({ 'status': 0, 'msg': 'ok', 'results': serializers.V2BookModelSerializer
      (book_objs, many=True).data })

总结:

  model层:

from django.db import models

# 图书管理系统:Book、Author、AuthorDetail、Publish
"""
Book表: name、price、img、authors、publish、is_delete、create_time
Publish表: name、address、is_delete、create_time
Author表: name、age、is_delete、create_time
AuthorDetail表: mobile, author、is_delete、create_time
"""

# 1) 基表
class BaseModel(models.Model):
    is_delete = models.BooleanField(default=False)
    create_time = models.DateTimeField(auto_now_add=True)

    # 作为基表的Model不能在数据库中形成对应的表,设置 abstract = True
    class Meta:
        abstract = True


class Book(BaseModel):
    """name、price、img、authors、publish、is_delete、create_time"""
    name = models.CharField(max_length=64)
    price = models.DecimalField(max_digits=5, decimal_places=2)
    img = models.ImageField(upload_to='img', default='img/default.jpg')
    publish = models.ForeignKey(
        to='Publish',
        db_constraint=False,
        related_name='books',
        on_delete=models.DO_NOTHING,
    )
    authors = models.ManyToManyField(
        to='Author',
        db_constraint=False,
        related_name='books'
    )


    @property
    def publish_name(self):
        return self.publish.name

    @property
    def author_list(self):
        return self.authors.values('name', 'age', 'detail__mobile').all()

    class Meta:
        db_table = 'book'
        verbose_name = '书籍'
        verbose_name_plural = verbose_name
    def __str__(self):
        return self.name

class Publish(BaseModel):
    """name、address、is_delete、create_time"""
    name = models.CharField(max_length=64)
    address = models.CharField(max_length=64)

    class Meta:
        db_table = 'publish'
        verbose_name = '出版社'
        verbose_name_plural = verbose_name
    def __str__(self):
        return self.name

class Author(BaseModel):
    """name、age、is_delete、create_time"""
    name = models.CharField(max_length=64)
    age = models.IntegerField()

    class Meta:
        db_table = 'author'
        verbose_name = '作者'
        verbose_name_plural = verbose_name
    def __str__(self):
        return self.name

class AuthorDetail(BaseModel):
    """mobile, author、is_delete、create_time"""
    mobile = models.CharField(max_length=11)
    author = models.OneToOneField(
        to='Author',
        db_constraint=False,
        related_name='detail',
        on_delete=models.CASCADE,
    )

    class Meta:
        db_table = 'author_detail'
        verbose_name = '作者详情'
        verbose_name_plural = verbose_name
    def __str__(self):
        return '%s的详情' % self.author.name
model

  exception层:

from rest_framework.views import exception_handler as drf_exception_handler
from rest_framework.views import Response
from rest_framework import status
def exception_handler(exc, context):
    # drf的exception_handler做基础处理
    response = drf_exception_handler(exc, context)
    # 为空,自定义二次处理
    if response is None:
        print('%s - %s - %s' % (context['view'], context['request'].method, exc))
        return Response({
            'detail': '服务器错误'
        }, status=status.HTTP_500_INTERNAL_SERVER_ERROR, exception=True)
    return response
exception

  serializers层:

from rest_framework.serializers import ModelSerializer, SerializerMethodField
from rest_framework.exceptions import ValidationError
from . import models


class PublishModelSerializer(ModelSerializer):
    class Meta:
        model = models.Publish
        fields = ('name', 'address')

class BookModelSerializer(ModelSerializer):
    # 了解: 该方式设置的序列化字段,必须在fields中声明
    # publish_address = SerializerMethodField()
    # def get_publish_address(self, obj):
    #     return obj.publish.address

    # 自定义连表深度 - 子序列化方式
    publish = PublishModelSerializer()

    class Meta:
        # 序列化类关联的model类
        model = models.Book
        # 参与序列化的字段
        fields = ('name', 'price', 'img', 'author_list', 'publish')

        # 了解知识点
        # 所有字段
        # fields = '__all__'
        # 与fields不共存,exclude排除哪些字段
        # exclude = ('id', 'is_delete', 'create_time')
        # 自动连表深度
        # depth = 1

class BookModelDeserializer(ModelSerializer):
    class Meta:
        model = models.Book
        fields = ('name', 'price', 'publish', 'authors')
        # extra_kwargs 用来完成反序列化字段的 系统校验规则
        extra_kwargs = {
            'name': {
                'required': True,
                'min_length': 1,
                'error_messages': {
                    'required': '必填项',
                    'min_length': '太短',
                }
            }
        }

    def validate_name(self, value):
        # 书名不能包含 g 字符
        if 'g' in value.lower():
            raise ValidationError('该g书不能出版')
        return value

    def validate(self, attrs):
        publish = attrs.get('publish')
        name = attrs.get('name')
        if models.Book.objects.filter(name=name, publish=publish):
            raise ValidationError({'book': '该书已存在'})
        return attrs

    # ModelSerializer类已经帮我们实现了 create 与 update 方法


"""
1) fields中设置所有序列化与反序列化字段
2) extra_kwargs划分只序列化或只反序列化字段
    write_only:只反序列化
    read_only:只序列化
    自定义字段默认只序列化(read_only)
3) 设置反序列化所需的 系统、局部钩子、全局钩子 等校验规则
"""
from rest_framework.serializers import ListSerializer

# 重点:ListSerializer与ModelSerializer建立关联的是:
# ModelSerializer的Meta类的 - list_serializer_class
class V2BookListSerializer(ListSerializer):
    def update(self, instance, validated_data):
        # print(instance)  # 要更新的对象们
        # print(validated_data)  # 更新的对象对应的数据们
        # print(self.child)  # 服务的模型序列化类 - V2BookModelSerializer
        for index, obj in enumerate(instance):
            self.child.update(obj, validated_data[index])
        return instance



class V2BookModelSerializer(ModelSerializer):
    class Meta:
        model = models.Book
        fields = ('name', 'price', 'img', 'author_list', 'publish_name', 'publish', 'authors')
        extra_kwargs = {
            'name': {
                'required': True,
                'min_length': 1,
                'error_messages': {
                    'required': '必填项',
                    'min_length': '太短',
                }
            },
            'publish': {
                'write_only': True
            },
            'authors': {
                'write_only': True
            },
            'img': {
                'read_only': True,
            },
            'author_list': {
                'read_only': True,
            },
            'publish_name': {
                'read_only': True,
            }
        }

        # 群改,需要设置 自定义ListSerializer,重写群改的 update 方法
        list_serializer_class = V2BookListSerializer

    def validate_name(self, value):
        # 书名不能包含 g 字符
        if 'g' in value.lower():
            raise ValidationError('该g书不能出版')
        return value

    def validate(self, attrs):
        publish = attrs.get('publish')
        name = attrs.get('name')
        if models.Book.objects.filter(name=name, publish=publish):
            raise ValidationError({'book': '该书已存在'})
        return attrs
serializer

  url:

from django.conf.urls import url

from . import views

urlpatterns = [
    url(r'^books/$', views.Book.as_view()),
    url(r'^books/(?P<pk>.*)/$', views.Book.as_view()),

    url(r'^publishes/$', views.Publish.as_view()),
    url(r'^publishes/(?P<pk>.*)/$', views.Publish.as_view()),

    url(r'^v2/books/$', views.V2Book.as_view()),
    url(r'^v2/books/(?P<pk>.*)/$', views.V2Book.as_view()),
]
urls

  view层:

from rest_framework.views import APIView
from rest_framework.response import Response

from . import models, serializers

class Publish(APIView):
    def get(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:
            try:
                publish_obj = models.Publish.objects.get(pk=pk, is_delete=False)
                publish_data = serializers.PublishModelSerializer(publish_obj).data
            except:
                return Response({
                    'status': 1,
                    'msg': '出版社不存在'
                })
        else:
            publish_query = models.Publish.objects.filter(is_delete=False).all()
            publish_data = serializers.PublishModelSerializer(publish_query, many=True).data
        return Response({
            'status': 0,
            'msg': 'ok',
            'results': publish_data
        })



class Book(APIView):
    def get(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:
            try:
                book_obj = models.Book.objects.get(pk=pk, is_delete=False)
                book_data = serializers.BookModelSerializer(book_obj).data
            except:
                return Response({
                    'status': 1,
                    'msg': '书籍不存在'
                })
        else:
            book_query = models.Book.objects.filter(is_delete=False).all()
            book_data = serializers.BookModelSerializer(book_query, many=True).data
        return Response({
            'status': 0,
            'msg': 'ok',
            'results': book_data
        })

    def post(self, request, *args, **kwargs):
        request_data = request.data
        book_ser = serializers.BookModelDeserializer(data=request_data)
        # 当校验失败,马上终止当前视图方法,抛异常返回给前台
        book_ser.is_valid(raise_exception=True)
        book_obj = book_ser.save()
        return Response({
            'status': 0,
            'msg': 'ok',
            'results': serializers.BookModelSerializer(book_obj).data
        })



class V2Book(APIView):
    # 单查:有pk
    # 群查:无pk
    def get(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:
            try:
                book_obj = models.Book.objects.get(pk=pk, is_delete=False)
                book_data = serializers.V2BookModelSerializer(book_obj).data
            except:
                return Response({
                    'status': 1,
                    'msg': '书籍不存在'
                })
        else:
            book_query = models.Book.objects.filter(is_delete=False).all()
            book_data = serializers.V2BookModelSerializer(book_query, many=True).data
        return Response({
            'status': 0,
            'msg': 'ok',
            'results': book_data
        })

    # 单增:传的数据是与model对应的字典
    # 群增:传的数据是 装多个 model对应字典 的列表
    def post(self, request, *args, **kwargs):
        request_data = request.data
        if isinstance(request_data, dict):
            many = False
        elif isinstance(request_data, list):
            many = True
        else:
            return Response({
                'status': 1,
                'msg': '数据有误',
            })
        book_ser = serializers.V2BookModelSerializer(data=request_data, many=many)
        # 当校验失败,马上终止当前视图方法,抛异常返回给前台
        book_ser.is_valid(raise_exception=True)
        book_result = book_ser.save()
        return Response({
            'status': 0,
            'msg': 'ok',
            'results': serializers.V2BookModelSerializer(book_result, many=many).data
        })

    # 单删:有pk
    # 群删:有pks   |  {"pks": [1, 2, 3]}
    def delete(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:
            pks = [pk]
        else:
            pks = request.data.get('pks')
        if models.Book.objects.filter(pk__in=pks, is_delete=False).update(is_delete=True):
            return Response({
                'status': 0,
                'msg': '删除成功',
            })
        return Response({
            'status': 1,
            'msg': '删除失败',
        })

    # 单整体改: 对 v2/books/(pk)/ 传的数据是与model对应的字典{name|price|publish|authors}
    def put(self, request, *args, **kwargs):
        request_data = request.data
        pk = kwargs.get('pk')
        old_book_obj = models.Book.objects.filter(pk=pk).first()
        # 目的:将众多数据的校验交给序列化类来处理 - 让序列化类扮演反序列化角色,校验成功后,序列化类来帮你入库
        book_ser = serializers.V2BookModelSerializer(instance=old_book_obj, data=request_data, partial=False)
        book_ser.is_valid(raise_exception=True)
        # 校验通过,完成数据的更新:要更新的目标,用来更新的新数据
        book_obj = book_ser.save()

        return Response({
            'status': 0,
            'msg': 'ok',
            'results': serializers.V2BookModelSerializer(book_obj).data
        })


    # 单局部改:对 v2/books/(pk)/ 传的数据,数据字段key都是选填
    # 群局部改:
    # 请求数据 - [{pk:1, name:123}, {pk:3, price:7}, {pk:7, publish:2}]
    def patch(self, request, *args, **kwargs):
        request_data = request.data
        pk = kwargs.get('pk')

        # 将单改,群改的数据都格式化成 pks=[要需要的对象主键标识] | request_data=[每个要修改的对象对应的修改数据]
        if pk and isinstance(request_data, dict):  # 单改
            pks = [pk, ]
            request_data = [request_data, ]
        elif not pk and isinstance(request_data, list): # 群改
            pks = []
            for dic in request_data:  # 遍历前台数据[{pk:1, name:123}, {pk:3, price:7}, {pk:7, publish:2}],拿一个个字典
                pk = dic.pop('pk', None)
                if pk:
                    pks.append(pk)
                else:
                    return Response({
                        'status': 1,
                        'msg': '数据有误',
                    })
        else:
            return Response({
                'status': 1,
                'msg': '数据有误',
            })

        # pks与request_data数据筛选,
        # 1)将pks中的没有对应数据的pk与数据已删除的pk移除,request_data对应索引位上的数据也移除
        # 2)将合理的pks转换为 objs
        objs = []
        new_request_data = []
        for index, pk in enumerate(pks):
            try:
                # pk对应的数据合理,将合理的对象存储
                obj = models.Book.objects.get(pk=pk)
                objs.append(obj)
                # 对应索引的数据就需要保存下来
                new_request_data.append(request_data[index])
            except:
                # 重点:反面教程 - pk对应的数据有误,将对应索引的data中request_data中移除
                # index = pks.index(pk)
                # request_data.pop(index)
                continue

        book_ser = serializers.V2BookModelSerializer(instance=objs, data=new_request_data, partial=True, many=True)
        book_ser.is_valid(raise_exception=True)
        book_objs = book_ser.save()

        return Response({
            'status': 0,
            'msg': 'ok',
            'results': serializers.V2BookModelSerializer(book_objs, many=True).data
        })



    # 总结:
    """
    1)单整体修改:
    V2BookModelSerializer(
        instance=要被更新的对象, 
        data=用来更新的数据,
        partial=默认False,必须的字段全部参与校验
    )
    2)单局部修改:
    V2BookModelSerializer(
        instance=要被更新的对象, 
        data=用来更新的数据,
        partial=设置True,必须的字段都变为选填字段
    )
    注:partial设置True的本质就是使字段 required=True 校验规则失效
    """
view

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转载自www.cnblogs.com/LZXlzmmddtm/p/11695944.html