from typing import Optional, Union

from bson import ObjectId
from pydantic import BaseModel, Field


# # mongodb  _id 类型
# class OId(ObjectId):
#     @classmethod
#     def __get_validators__(cls):
#         yield cls.validate
#
#     @classmethod
#     def validate(cls, v):
#         try:
#             return ObjectId(v)
#         except:
#             raise ValueError('无效的格式')


class DBBase(BaseModel):
    id: str = Field(None, alias='_id')