customize error messages of Cerberus(https://github.com/pyeve/cerberus)

gistfile1.txt

"""
https://stackoverflow.com/questions/47730454/how-can-i-customize-error-messages-of-cerberus
"""

import cerberus


class CustomErrorHandler(cerberus.errors.BasicErrorHandler):
    messages = cerberus.errors.BasicErrorHandler.messages.copy()
    messages[cerberus.errors.REQUIRED_FIELD.code] = '用户名为必填项'
    messages[cerberus.errors.BAD_TYPE.code] = '用户名必须是字符串'

v = cerberus.Validator(
    {
        'username': {
            'required': True,
            'type': 'string',
        }
    },
    error_handler=CustomErrorHandler
)

print(v.validate({}))
print(v.errors)

print(v.validate({'username': 1}))
print(v.errors)