Access Token and Refresh Token field length too small #1523
Description
Describe the bug
The Access Token and Refresh Token field are too small when using Postgres (VARCHAR(1024)).
When using OAuth2 providers like Authentik with a token algorithm like RS256, the access tokens can easily exceed the max length of 1024 chars, thus causing this error:
sqlalchemy.exc.DataError: (psycopg.errors.StringDataRightTruncation) value too long for type character varying(1024)
To Reproduce
Steps to reproduce the behavior:
- Setup OAuth authentication with SQLAlchemy. With a table that's defined like this
from fastapi_users.db import (
SQLAlchemyBaseOAuthAccountTableUUID,
)
class OAuthAccount(SQLAlchemyBaseOAuthAccountTableUUID, Base):
pass- Setup a OAuth provider with access token encryption/signing
- Try to login
- Fail to login because the access token couldn't be saved.
Expected behavior
The DB column data type being large enough to store the access/refresh token, thus enabling logging in.
Configuration
- Python version : 3.13
- FastAPI version : 0.115.12
- FastAPI Users version : 14.0.1
FastAPI Users configuration
db.py
from collections.abc import AsyncGenerator
from typing import Optional
from fastapi import Depends
from fastapi_users.db import (
SQLAlchemyBaseUserTableUUID,
SQLAlchemyUserDatabase,
SQLAlchemyBaseOAuthAccountTableUUID,
)
from sqlalchemy import String
from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
from sqlalchemy.orm import Mapped, relationship, mapped_column
from media_manager.database import Base
from media_manager.database import db_url
class OAuthAccount(SQLAlchemyBaseOAuthAccountTableUUID, Base):
# my current setup already includes a fix for this error, by just overwriting the default type
access_token: Mapped[str] = mapped_column(String(length=4096), nullable=False)
refresh_token: Mapped[Optional[str]] = mapped_column(
String(length=4096), nullable=True
)
pass
class User(SQLAlchemyBaseUserTableUUID, Base):
oauth_accounts: Mapped[list[OAuthAccount]] = relationship(
"OAuthAccount", lazy="joined"
)
engine = create_async_engine(db_url, echo=False)
async_session_maker = async_sessionmaker(engine, expire_on_commit=False)
async def get_async_session() -> AsyncGenerator[AsyncSession, None]:
async with async_session_maker() as session:
yield session
async def get_user_db(session: AsyncSession = Depends(get_async_session)):
yield SQLAlchemyUserDatabase(session, User, OAuthAccount)users.py
import uuid
from fastapi_users import schemas
class UserRead(schemas.BaseUser[uuid.UUID]):
pass
class UserCreate(schemas.BaseUserCreate):
pass
class UserUpdate(schemas.BaseUserUpdate):
pass
Additional context
I'd be happy to help contribute and submit a PR fixing this.