标签：name marshmallow 示例 python fields result print data email
"""
棉花糖，序列化工具
核心方法：
序列化：schema.dump(object)、schema.dumps(object)
反序列化：schema.load(dict)
"""
import uuid
from datetime import datetime
from pprint import pprint
from marshmallow import Schema, fields, post_load, ValidationError, validate
"""
序列化和反序列化
"""
print(" v v v")
print("创建自定义对象----------------------------------------v v")
print(" v")
# 创建自定义对象object
class User:
def __init__(self, name, email, created_at):
self.name = name
self.email = email
self.created_at = created_at
print(" v v v")
print("创建Schema的两种方式----------------------------------v v")
print(" v")
# 创建结构描述
# 方式一
class UserSchema(Schema):
name = fields.Str()
email = fields.Email()
created_at = fields.DateTime()
@post_load
def make_user(self, data, **kwargs):
return User(**data)
# 方式二
UserSchema2 = Schema.from_dict({"name": fields.Str(), "email": fields.Email(), "created_at": fields.DateTime()})
print(" v v v")
print("序列化对象示例----------------------------------------v v")
print(" v")
# 序列化对象
user = User("zht", "2862058843@163.com", datetime.now())
userSchema = UserSchema()
result = userSchema.dump(user)
# 美化输出
pprint(result)
print(type(result))
userSchema2 = UserSchema2()
result2 = userSchema2.dump(user)
pprint(result2)
# print(result)
# 转成json字符串
json_result = userSchema2.dumps(user)
pprint(json_result)
print(type(json_result))
print(" v v v")
print("序列化对象示例(过滤输出)-------------------------------v v")
print(" v")
# 过滤输出
userSchema2 = UserSchema2(only=('name', 'email'))
json_result = userSchema2.dump(user)
pprint(json_result)
print(type(json_result))
print(json_result['name'])
print(" v v v")
print("返序列化对象示例--------------------------------------v v")
print(" v")
# 反序列化对象 注意的是 字典里的key，对象构造函数一定要有此key
user_data = {
"created_at": "2014-08-11T05:26:03.869245",
"email": "ken@yahoo.com",
"name": "Ken",
}
userSchema3 = UserSchema()
result = userSchema3.load(user_data)
pprint(result)
print(type(result))
# 反序列化对象集合
user1 = User("zht1", "2862058843@163.com", datetime.now())
user2 = User("zht2", "2862058843@164.com", datetime.now())
user3 = User("zht3", "2862058843@165.com", datetime.now())
users = [user1, user2, user3]
userSchemas = UserSchema(many=True)
result = userSchemas.dump(users)
pprint(result)
"""
验证属性值
"""
print(" v v v")
print("验证属性值示例----------------------------------------v v")
print(" v")
# 验证一个对象
print("验证一个对象")
try:
result = UserSchema().load({"name": "zht", "email": "zht"})
print(result)
except ValidationError as e:
print(e.messages)
print(e.valid_data)
# 验证多个对象
print("验证多个对象")
class BandMemberSchema(Schema):
name = fields.String(required=True)
email = fields.Email()
user_data = [
{"email": "mick@stones.com", "name": "Mick"},
{"email": "invalid", "name": "Invalid"}, # invalid email
{"email": "keith@stones.com", "name": "Keith"},
{"email": "charlie@stones.com"}, # missing "name"
]
try:
BandMemberSchema(many=True).load(user_data)
print(result)
except ValidationError as e:
print(e.messages)
print(e.valid_data)
# 通过传递 validate参数传递验证器对字段进行验证
print("通过传递 validate参数传递验证器对字段进行验证")
class MemberSchema(Schema):
name = fields.Str(validate=validate.Length(min=1)) # 最小字符长度
permission = fields.Str(validate=validate.OneOf(["read", "write", "admin"])) # 必须是其中一个
age = fields.Int(validate=validate.Range(min=18, max=40)) # 年龄必须是18到40
in_data = {"name": "1", "permission": "invalid", "age": 71}
try:
MemberSchema().load(in_data)
except ValidationError as e:
print(e.messages) # 输出针对每个字段的错误信息
print(e.valid_data) # 输出有效的字段 （验证通过的字段）
# 自己实现一个验证器
def validate_quantity(n):
if n < 0:
raise ValidationError("Quantity must be greater than 0.")
if n > 30:
raise ValidationError("Quantity must not be greater than 30.")
class ItemSchema(Schema):
quantity = fields.Integer(validate=validate_quantity)
in_data = {"quantity": -1}
try:
result = ItemSchema().load(in_data)
print(result)
except ValidationError as e:
print(e.messages) # 输出针对每个字段的错误信息
print(e.valid_data) # 输出有效的字段 （验证通过的字段）
# 自定义错误信息
print("自定义字段验证required的错误消息")
class TRequiredSchema(Schema):
name = fields.String(required=True)
age = fields.Integer(required=True, error_messages={"required": "Age is required."})
city = fields.String(
required=True,
error_messages={"required": {"message": "City required", "code": 400}},
)
email = fields.Email()
try:
result = TRequiredSchema().load({"email": "foo@bar.com"})
except ValidationError as err:
pprint(err.messages)
# {'age': ['Age is required.'],
# 'city': {'code': 400, 'message': 'City required'},
# 'name': ['Missing data for required field.']}
print("指定默认值")
# 指定默认
class DefaultSchema(Schema):
id = fields.UUID(missing=uuid.uuid1)
birthdate = fields.DateTime(default=datetime(2017, 9, 29))
name = fields.String(default="火")
print(DefaultSchema().load({}))
# {'id': UUID('337d946c-32cd-11e8-b475-0022192ed31b')}
print(DefaultSchema().dump({}))
# {'birthdate': '2017-09-29T00:00:00+00:00'}
标签：name,marshmallow,示例,python,fields,result,print,data,email 来源： https://www.cnblogs.com/zht-ytr/p/14041778.html
本站声明： 1. iCode9 技术分享网（下文简称本站）提供的所有内容，仅供技术学习、探讨和分享； 2. 关于本站的所有留言、评论、转载及引用，纯属内容发起人的个人观点，与本站观点和立场无关； 3. 关于本站的所有言论和文字，纯属内容发起人的个人观点，与本站观点和立场无关； 4. 本站文章均是网友提供，不完全保证技术分享内容的完整性、准确性、时效性、风险性和版权归属；如您发现该文章侵犯了您的权益，可联系我们第一时间进行删除； 5. 本站为非盈利性的个人网站，所有内容不会用来进行牟利，也不会利用任何形式的广告来间接获益，纯粹是为了广大技术爱好者提供技术内容和技术思想的分享性交流网站。