ObjectId with Pydantic protocol

main.py

from typing import Type, Callable, Any

from bson.objectid import ObjectId, InvalidId
from pydantic import BaseModel, ValidationError
from pydantic_core import CoreSchema, core_schema


class PydanticObjectId(ObjectId):
    @classmethod
    def __get_pydantic_core_schema__(
        cls, source: Type[Any], handler: Callable[[Any], CoreSchema]
    ) -> CoreSchema:
        return core_schema.no_info_after_validator_function(
            cls._validate, core_schema.any_schema()
        )

    @classmethod
    def _validate(cls, value: Any) -> ObjectId:
        try:
            return ObjectId(value)
        except (InvalidId, TypeError) as e:
            raise ValueError("Not a valid ObjectId") from e


class Model(BaseModel):
    id: PydanticObjectId


print(Model.model_validate({"id": ObjectId()}))
print(Model.model_validate({"id": str(ObjectId())}))

try:
    Model.model_validate({"id": 123})
except ValidationError as e:
    print(e.errors())