backends.py

from functools import lru_cache
from typing import List

from fastapi_users.authentication import (
    AuthenticationBackend,
    BearerTransport,
    CookieTransport,
    JWTStrategy,
)
from fastapi_users.authentication.strategy.base import Strategy
from fastapi_users.authentication.transport.base import Transport

from utils import get_settings


@lru_cache
def get_backends() -> List[AuthenticationBackend]:
    return [
        AuthenticationBackend(
            name="jwt", transport=_get_bearer_transport(), get_strategy=_get_strategy
        ),
        AuthenticationBackend(
            name="cookie", transport=_get_cookie_transport(), get_strategy=_get_strategy
        ),
    ]


def _get_bearer_transport() -> Transport:
    return BearerTransport(tokenUrl="auth/jwt/login")


def _get_cookie_transport() -> Transport:
    return CookieTransport(cookie_max_age=get_settings().AUTH_ACCESS_TOKEN_EXPIRE_SECONDS)


def _get_strategy() -> Strategy:
    return JWTStrategy(
        secret=get_settings().AUTH_JWT_SECRET,
        lifetime_seconds=get_settings().AUTH_ACCESS_TOKEN_EXPIRE_SECONDS,
    )