FastApi & MongoDB

FastApi & MongoDB - the full guide: https://github.com/tiangolo/fastapi/issues/1515

# -*- coding: utf-8 -*-
from datetime import datetime
from typing import Optional

from bson import ObjectId
from bson.errors import InvalidId
from fastapi import FastAPI
from pydantic import BaseConfig, BaseModel, Field

app = FastAPI()


class PyObjectId(str):
    @classmethod
    def __get_validators__(cls):
        yield cls.validate

    @classmethod
    def validate(cls, v):
　　　　　if isinstance(v, ObjectId):
　　　　　    return v
　　     try:
            return ObjectId(str(v))
        except InvalidId:
            raise ValueError("Not a valid ObjectId")


class MongoModel(BaseModel):
    id: Optional[PyObjectId] = Field(..., alias='_id')

    class Config(BaseConfig):
        json_encoders = {
            datetime: lambda dt: dt.isoformat(),
            ObjectId: lambda oid: str(oid),
        }


class User(MongoModel):
    name: str = Field()


@app.post('/me', response_model=User)
def save_me(body: User):
    assert isinstance(body.id, ObjectId)
    return body