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jsonschema - 校验Json内容和格式

article 2024/11/17 6:30:04

1、创建对象

from pydantic import BaseModel
from typing import List

class Person(BaseModel):
    name: str
    age: int

class Student(Person): 
    level: int = 16
    friends: List[Person]

2、生成 schema

schema = Student.model_json_schema()

内容如下

{'$defs': {'Person': {'properties': {'name': {'title': 'Name', 'type': 'string'}, 'age': {'title': 'Age', 'type': 'integer'}}, 'required': ['name', 'age'], 'title': 'Person', 'type': 'object'}}, 'properties': {'name': {'title': 'Name', 'type': 'string'}, 'age': {'title': 'Age', 'type': 'integer'}, 'level': {'title': 'Level', 'type': 'integer'}, 'friends': {'items': {'$ref': '#/$defs/Person'}, 'title': 'Friends', 'type': 'array'}}, 'required': ['name', 'age', 'level', 'friends'], 'title': 'Student', 'type': 'object'}

3、生成测试数据

对象转 json 字符串


fre0 = Person(age=15, name='alice') 
fre1 = Person(age=17, name='Allen') 

stu = Student(age=15, name='Betty', level = 3, friends = [fre0, fre1]) 

d1 = stu.__dict__
print(d1) 

# {'name': 'Betty', 'age': 15, 'level': 3, 'friends': {name='alice', age=15}, Person(name='Allen', age=17)]}

import json 
json.dumps(d1, default=lambda obj:obj.__dict__, sort_keys=True, indent=4 )  

# Object of type Person is not JSON serializable
json_str = '''
{"age": 15, "friends": [{"age": 15, "name": "alice"}, {"age": 17, "name": "Allen"}], "level": 3, "name": "Betty"}
'''

4、校验 validate

d2 = json.loads(json_str)

schema = {'$defs': {'Person': {'properties': {'name': {'title': 'Name', 'type': 'string'}, 'age': {'title': 'Age', 'type': 'integer'}}, 'required': ['name', 'age'], 'title': 'Person', 'type': 'object'}}, 'properties': {'name': {'title': 'Name', 'type': 'string'}, 'age': {'title': 'Age', 'type': 'integer'}, 'level': {'title': 'Level', 'type': 'integer'}, 'friends': {'items': {'$ref': '#/$defs/Person'}, 'title': 'Friends', 'type': 'array'}}, 'required': ['name', 'age', 'level', 'friends'], 'title': 'Student', 'type': 'object'}

from jsonschema import validate

try:
    ret = validate(instance=d2, schema=schema)
    print(ret) 
    # 返回 None 代表没问题 
    if ret == None:
        print('-- json 格式符合')
    else:
        print('xx json 格式不符合') 
except Exception as err:
    print('xx json 验证失败 ')

5、错误情况

以上json 没问题，如果把 json 数据或字典故意处理为错误的数据类型，或格式，如下：

{"age": 15, "friends": [{"age": 15, "name": "alice"}, {"age": 17, "name": "Allen"}], "level": 3, "name": 12}

validate 会报出 Error

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/xxx/python3.11/site-packages/jsonschema/validators.py", line 1332, in validate
    raise error
jsonschema.exceptions.ValidationError: 12 is not of type 'string'

Failed validating 'type' in schema['properties']['name']:
    {'title': 'Name', 'type': 'string'}

On instance['name']:
    12