Files
ZY-Agent/backend/app/gateway/auth/api_key_backend.py
T
2026-06-28 11:40:27 +08:00

98 lines
3.5 KiB
Python

"""API key authentication backend (Stage 1 PR2).
Resolves an ``Authorization: Bearer dfk_...`` token into a
``ServicePrincipal`` + workspace + scopes, so ``AuthMiddleware`` can
stamp the same contextvars a cookie-authenticated human would set
(spec D1: user_id = SA.id).
"""
from __future__ import annotations
import logging
from dataclasses import dataclass
from deerflow.auth.tokens import hash_api_key, split_prefix
logger = logging.getLogger(__name__)
@dataclass(frozen=True)
class ServicePrincipal:
"""Non-human principal backing an API key. Satisfies the
``deerflow.runtime.user_context.CurrentUser`` protocol."""
id: str
is_service_account: bool = True
def parse_scopes(scopes: str) -> list[str]:
"""Parse a comma-separated scope string into a permission list.
``"threads:read, threads:write"`` -> ``["threads:read", "threads:write"]``.
Empty / whitespace-only segments are dropped.
"""
return [s.strip() for s in scopes.split(",") if s.strip()]
@dataclass(frozen=True)
class ApiKeyAuthResult:
"""Everything ``AuthMiddleware`` needs to stamp request state +
contextvars from a verified API key."""
principal: ServicePrincipal
workspace_id: str
role: str
permissions: list[str]
class APIKeyAuthBackend:
def __init__(self, *, api_key_repo, service_account_repo, workspace_repo) -> None:
self._api_key_repo = api_key_repo
self._service_account_repo = service_account_repo
self._workspace_repo = workspace_repo
async def authenticate(self, token: str) -> ApiKeyAuthResult | None:
"""Resolve a plaintext token to an auth result, or None (→ 401)."""
# Look up by the indexed public prefix; the repo constant-time
# verifies the full hash.
key = await self._api_key_repo.get_active_by_hash(hash_api_key(token), key_prefix=split_prefix(token))
if key is None:
return None
sa = await self._service_account_repo.get_active(key["service_account_id"])
if sa is None:
return None
# SA is not a workspace *member* — bypass the membership filter
# with the documented user_id=None admin/migration path.
workspace = await self._workspace_repo.get(sa["workspace_id"], user_id=None)
if workspace is None or workspace["status"] != "active":
return None
# Best-effort: never block the request if the timestamp write fails.
try:
await self._api_key_repo.touch_last_used(key["id"])
except Exception: # noqa: BLE001 — best-effort, log and continue
logger.warning("touch_last_used failed for api_key %s", key["id"], exc_info=True)
return ApiKeyAuthResult(
principal=ServicePrincipal(id=sa["id"]),
workspace_id=sa["workspace_id"],
role=sa["role"],
permissions=parse_scopes(key["scopes"]),
)
def build_api_key_backend() -> APIKeyAuthBackend | None:
"""Construct a backend from the global session factory, or None when
persistence is the in-memory backend (no DB → no API keys)."""
from deerflow.persistence.api_key import ApiKeyRepository
from deerflow.persistence.engine import get_session_factory
from deerflow.persistence.service_account import ServiceAccountRepository
from deerflow.persistence.workspace import WorkspaceRepository
sf = get_session_factory()
if sf is None:
return None
return APIKeyAuthBackend(api_key_repo=ApiKeyRepository(sf), service_account_repo=ServiceAccountRepository(sf), workspace_repo=WorkspaceRepository(sf))