Files
fastapi-toolsets/src/fastapi_toolsets/security/abc.py
2026-04-01 14:53:51 -04:00

54 lines
1.6 KiB
Python

"""Abstract base class for authentication sources."""
import inspect
from abc import ABC, abstractmethod
from typing import Any, Callable
from fastapi import Request
from fastapi.security import SecurityScopes
from fastapi_toolsets.exceptions import UnauthorizedError
def _ensure_async(fn: Callable[..., Any]) -> Callable[..., Any]:
"""Wrap *fn* so it can always be awaited, caching the coroutine check at init time."""
if inspect.iscoroutinefunction(fn):
return fn
async def wrapper(*args: Any, **kwargs: Any) -> Any:
return fn(*args, **kwargs)
return wrapper
class AuthSource(ABC):
"""Abstract base class for authentication sources."""
def __init__(self) -> None:
"""Set up the default FastAPI dependency signature."""
source = self
async def _call(
request: Request,
security_scopes: SecurityScopes, # noqa: ARG001
) -> Any:
credential = await source.extract(request)
if credential is None:
raise UnauthorizedError()
return await source.authenticate(credential)
self._call_fn: Callable[..., Any] = _call
self.__signature__ = inspect.signature(_call)
@abstractmethod
async def extract(self, request: Request) -> str | None:
"""Extract the raw credential from the request without validating."""
@abstractmethod
async def authenticate(self, credential: str) -> Any:
"""Validate a credential and return the authenticated identity."""
async def __call__(self, **kwargs: Any) -> Any:
"""FastAPI dependency dispatch."""
return await self._call_fn(**kwargs)