01-创建序列化类
# 方式一：
publish_list = models.Publish.objects.all()
# 导入序列化组件
from django.core import serializers serializers.serialize("json", publish_list)
# 方式二：
# 为queryset和model对象做序列化 class PublishSerializers(serializers.Serializer):
# 添加做序列化的字段
name = serializers.CharField()
email = serializers.CharField() publish_list = models.Publish.objects.all() PublishSerializers(publish_list, many=True) PublishSerializers(model_obj)
Response
from rest_framework.response import Response
# 序列化 一对多 多对多 class BookSerializers(serializers.Serializer):
# 添加做序列化的字段
title = serializers.CharField()
price = serializers.CharField()
# 一对多
publish = serializers.CharField(source="publish.name") # 多对多
authors = serializers.SerializerMethodField() def get_authors(self, obj):
temp = []
for obj in obj.authors.all():
temp.append(obj.name)
02-ModelSerializer
# 等同于上面的 from rest_framework.views import APIView class BookModelSerializers(serializers.ModelSerializer):
class Meta:
model = Book # 表名
fields = "__all__" class BookView(APIView):
def get(self, request):
book_list = Book.objects.all()
bs = BookModelSerializers(book_list, many=True) return Response(bs.data) def post(self):
pass
03-提交post请求
class BookView(APIView):
def get(self, request):
'''
获取书籍
:param request:
:return:
'''
book_list = Book.objects.all()
bs = BookModelSerializers(book_list, many=True) return Response(bs.data) def post(self, request):
'''
添加书籍
:return:
'''
# post请求的数据
bs = BookModelSerializers(data=request.data)
if bs.is_valid():
bs.save() # 调用的是create方法
# 返回的是添加的数据
return Response(bs.data)
else:
# 错误的数据
return HttpResponse(bs.errors)
04-重写save中create方法
class BookModelSerializers(serializers.ModelSerializer):
class Meta:
model = Book # 表名
fields = "__all__" publish = serializers.CharField(source="publish.pk)
# 针对一对多字段publish，会报错，所以重写create方法
def create(self, validated_data):
book = Book.objects.create(title=validated_data["title"], price = validated_data["price"], pub_date = validated_data["pub_date"])
book.authors.add(*validated_data["authors"]) return book
05-自定义方法
class UserInfoSerializer(serializers.ModelSerializer):
type = serializers.CharField(source="get_user_type_display")
group = serializers.CharField(source="group.title")
rls = serializers.SerializerMethodField() def get_rls(self, row):
# 获取用户所有的角色
role_obj_list = row.roles.all()
ret = []
# 获取角色的id和名字
# 以字典的键值对方式显示
for item in role_obj_list:
ret.append({"id": item.id, "title": item.title})
return ret class Meta:
model = models.UserInfo
fields = ['id','username','password','type','group','rls']
06-自动序列化连表（depth）
class UserInfoSerializer(serializers.ModelSerializer):
class Meta:
model = models.UserInfo
#fields = "__all__"
fields = ['id','username','password','group','roles']
#表示连表的深度
depth = 1
07-生成url
# urls.py urlpatterns = [
re_path('(?P<version>[v1|v2]+)/group/(?P<pk>\d+)/', GroupView.as_view(),name = 'gp') #序列化生成url
]
class UserInfoSerializer(serializers.ModelSerializer):
# 获取url
group = serializers.HyperlinkedIdentityField(view_name='gp',lookup_field='group_id',lookup_url_kwarg='pk')
class Meta:
model = models.UserInfo
#fields = "__all__"
fields = ['id','username','password','group','roles']
#表示连表的深度
depth = 0
效果：
08-自定义数据验证规则
# 自定义验证规则
class GroupValidation(object):
def __init__(self,base):
self.base = base def __call__(self, value):
if not value.startswith(self.base):
message = "标题必须以%s为开头"%self.base
raise serializers.ValidationError(message) class UserGroupSerializer(serializers.Serializer):
title = serializers.CharField(validators=[GroupValidation('以我开头'),]) class UserGroupView(APIView):
def post(self,request,*args, **kwargs):
ser = UserGroupSerializer(data=request.data)
if ser.is_valid():
print(ser.validated_data['title'])
else:
print(ser.errors) return HttpResponse("用户提交数据验证")
09-序列化外键用嵌套的方法来实现
示例：
# 轮播图
class GoodsImageSerializer(serializers.ModelSerializer):
class Meta:
model = GoodsImage
fields = ("image",) # 商品列表页
class GoodsSerializer(serializers.ModelSerializer):
# 覆盖外键字段
category = CategorySerializer()
# images是数据库中设置的related_name="images"，把轮播图嵌套进来
images = GoodsImageSerializer(many=True)
class Meta:
model = Goods
fields = '__all__'
10-添加自定义字段 不在model字段内
class ForgetPWDSerializers(serializers.ModelSerializer):
re_password = serializers.CharField(write_only=True) class Meta:
model = UserModel
fields = ('username', 'password', 're_password')
原理：create最后在返回response体的时候，传递的参数serializer.data，其实做的是一个序列化的工作，它会依据你在class Meta里面设置的fields，去做序列化，将里面所有字段进行序列化，这个时候就会报错！
解决方法：write_only 设置这个属性为true,去确保create/update的时候这个字段被用到，序列化的时候，不被用到！
11-
12-获取choice的值
# 指定 source="get_category_display" CHOICES = ((1, "Python"), (2, "Go"), (3, "Linux"))
category = serializers.ChoiceField(choices=CHOICES, source="get_category_display", read_only=True)
13-设定不需要校验字段
# required=False id = serializers.IntegerField(required=False)
14-序列化字段与反序列化字段
# 前端 传 w_category 字段，序列化用category，反序列化用 w_category category = serializers.ChoiceField(choices=CHOICES, source="get_category_display", read_only=True)
w_category = serializers.ChoiceField(choices=CHOICES, write_only=True)
read_only=True 序列化字段；
write_only=True 反序列化字段；
book_obj = {
"title": "Alex的使用教程",
"w_category": 1,
"pub_time": "2018-10-09",
"publisher_id": 1,
"author_list": [1, 2]
}
class BookSerializer(serializers.Serializer):
id = serializers.IntegerField(required=False)
title = serializers.CharField(max_length=32, validators=[my_validate])
CHOICES = ((1, "Python"), (2, "Go"), (3, "Linux"))
category = serializers.ChoiceField(choices=CHOICES, source="get_category_display", read_only=True)
w_category = serializers.ChoiceField(choices=CHOICES, write_only=True)
pub_time = serializers.DateField()
publisher = PublisherSerializer(read_only=True)
publisher_id = serializers.IntegerField(write_only=True)
author = AuthorSerializer(many=True, read_only=True)
author_list = serializers.ListField(write_only=True)
def create(self, validated_data):
book = Book.objects.create(title=validated_data["title"], category=validated_data["w_category"],
pub_time=validated_data["pub_time"], publisher_id=validated_data["publisher_id"])
book.author.add(*validated_data["author_list"])
return book
def update(self, instance, validated_data):
instance.title = validated_data.get("title", instance.title)
instance.category = validated_data.get("category", instance.category)
instance.pub_time = validated_data.get("pub_time", instance.pub_time)
instance.publisher_id = validated_data.get("publisher_id", instance.publisher_id)
if validated_data.get("author_list"):
instance.author.set(validated_data["author_list"])
instance.save()
return instance
def validate_title(self, value):
if "python" not in value.lower():
raise serializers.ValidationError("标题必须含有python")
return value
def validate(self, attrs):
if attrs["w_category"] == 1 and attrs["publisher_id"] == 1:
return attrs
else:
raise serializers.ValidationError("分类以及标题不符合要求")
第一版
class BookSerializer(serializers.ModelSerializer):
category_display = serializers.SerializerMethodField(read_only=True)
publisher_info = serializers.SerializerMethodField(read_only=True)
authors = serializers.SerializerMethodField(read_only=True) def get_category_display(self, obj):
return obj.get_category_display() def get_authors(self, obj):
authors_query_set = obj.author.all()
return [{"id": author_obj.id, "name": author_obj.name} for author_obj in authors_query_set] def get_publisher_info(self, obj):
# obj 是我们序列化的每个Book对象
publisher_obj = obj.publisher
return {"id": publisher_obj.id, "title": publisher_obj.title} class Meta:
model = Book
# fields = ["id", "title", "pub_time"]
fields = "__all__"
# depth = 1
extra_kwargs = {"category": {"write_only": True}, "publisher": {"write_only": True},
"author": {"write_only": True}}
第二版ModelSerializer
15-put允许部分更新字段：partial=True
16-自定义校验方法 my_validate
# 三种 校验数据的方式：
1. 校验全部字段
validate 2. 校验单个字段 如：title
validate_title 3. 自定义校验方法
my_validate def my_validate(value):
if "敏感信息" in value.lower():
raise serializers.ValidationError("不能含有敏感信息")
else:
return value
my_validate的权重 高于 validate_title
17-设置depth = 1，获取外键字段及多对多字段的值
class BookSerializer(serializers.ModelSerializer):
# 获取 category 字段的选择 的值，是数字对应的值，而不是数字
category = serializers.CharField(source="get_category_display") class Meta:
model = Book
# fields = ["id", "title", "pub_time"]
fields = "__all__"
depth = 1
18-SerializerMethodField 用于 外键字段 等，只获取想要的字段的值
class BookSerializer(serializers.ModelSerializer):
category_display = serializers.SerializerMethodField(read_only=True)
publisher_info = serializers.SerializerMethodField(read_only=True)
authors = serializers.SerializerMethodField(read_only=True) def get_category_display(self, obj):
return obj.get_category_display() def get_authors(self, obj):
authors_query_set = obj.author.all()
return [{"id": author_obj.id, "name": author_obj.name} for author_obj in authors_query_set] def get_publisher_info(self, obj):
# obj 是我们序列化的每个Book对象
publisher_obj = obj.publisher
return {"id": publisher_obj.id, "title": publisher_obj.title} class Meta:
model = Book
# fields = ["id", "title", "pub_time"]
fields = "__all__"
# depth = 1
extra_kwargs = {"category": {"write_only": True}, "publisher": {"write_only": True},
"author": {"write_only": True}}
