fix(auth): resolve Bearer token in get_current_owner_id for mobile API auth

get_current_owner_id() only checked the session for authenticated users.
When the mobile app sends Authorization: Bearer <token>, there is no
session cookie, so the Depends(_get_owner_id) dependency raised HTTP 401
before the @require_login wrapper could resolve the Bearer token.

The function now checks three sources in order:
1. Session user dict (existing behavior)
2. request.state.api_token_user (cached by require_login or prior call)
3. Direct Bearer token resolution via _resolve_bearer_user (new)

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

app/utils/user_scope.py

@@ -20,13 +20,31 @@ from app.models import FileRecord
 logger = logging.getLogger(__name__)
 
 
+def _owner_id_from_user(user: dict) -> str | None:
+    """Extract the owner identifier from a user dict.
+
+    Priority: ``sub`` (OAuth subject) → ``preferred_username`` → ``email`` → ``id``.
+    """
+    return user.get("sub") or user.get("preferred_username") or user.get("email") or user.get("id")
+
+
 def get_current_owner_id(request: Request) -> str | None:
     """Extract the owner identifier for the current authenticated user.
 
-    The owner ID is derived from the user's session data.  It uses the
-    ``sub`` claim (OAuth subject) when available, falling back to
-    ``preferred_username`` or ``email``.  Returns ``None`` when no user
-    is authenticated.
+    The owner ID is derived from the user's session data or, when no session
+    is present, from a valid Bearer API token in the ``Authorization`` header.
+    This ensures that both browser-based (session cookie) and mobile/API
+    (Bearer token) requests are correctly identified.
+
+    Priority for user resolution:
+
+    1. Session ``user`` dict (set by OAuth or local login).
+    2. ``request.state.api_token_user`` (set by ``require_login`` or an
+       earlier call to this function during the same request).
+    3. Direct Bearer token look-up against the database.
+
+    Within the resolved user dict the owner ID is chosen as:
+    ``sub`` → ``preferred_username`` → ``email`` → ``id``.
 
     Args:
         request: The current FastAPI request with session data.
@@ -34,11 +52,41 @@ def get_current_owner_id(request: Request) -> str | None:
     Returns:
         A stable string identifier for the user, or ``None``.
     """
+    # 1. Session-based auth (most common for web UI)
     user = request.session.get("user")
-    if not user or not isinstance(user, dict):
-        return None
-    # Prefer 'sub' (OAuth subject), then 'preferred_username', then 'email', then 'id'
-    return user.get("sub") or user.get("preferred_username") or user.get("email") or user.get("id")
+    if user and isinstance(user, dict):
+        return _owner_id_from_user(user)
+
+    # 2. Already-resolved API token user (cached by require_login or a
+    #    prior dependency call during this request)
+    api_user = getattr(request.state, "api_token_user", None)
+    if isinstance(api_user, dict):
+        return _owner_id_from_user(api_user)
+
+    # 3. Direct Bearer token resolution – necessary when this function is
+    #    invoked as a FastAPI dependency (via Depends) which runs *before*
+    #    the @require_login decorator wrapper has had a chance to resolve
+    #    the token and populate request.state.api_token_user.
+    auth_header = request.headers.get("authorization", "")
+    if isinstance(auth_header, str) and auth_header.startswith("Bearer "):
+        try:
+            from app.auth import _resolve_bearer_user
+            from app.database import SessionLocal
+
+            db = SessionLocal()
+            try:
+                resolved = _resolve_bearer_user(request, db)
+            finally:
+                db.close()
+
+            if resolved:
+                # Cache so subsequent calls (and require_login) skip the DB
+                request.state.api_token_user = resolved
+                return _owner_id_from_user(resolved)
+        except Exception:
+            logger.debug("Bearer token resolution failed in get_current_owner_id")
+
+    return None
 
 
 def apply_owner_filter(query: Query, request: Request) -> Query:

tests/test_multi_user.py

@@ -18,7 +18,7 @@ from sqlalchemy.pool import StaticPool
 
 from app.config import settings
 from app.database import Base
-from app.models import FileRecord
+from app.models import ApiToken, FileRecord
 
 # ---------------------------------------------------------------------------
 # Fixtures
@@ -162,6 +162,116 @@ class TestGetCurrentOwnerId:
         request.session = {}
         assert get_current_owner_id(request) is None
 
+    @pytest.mark.unit
+    def test_resolves_from_api_token_user_state(self):
+        """get_current_owner_id should resolve from request.state.api_token_user."""
+        from app.utils.user_scope import get_current_owner_id
+
+        request = MagicMock()
+        request.session = {}
+        request.state.api_token_user = {
+            "id": "tok-owner",
+            "preferred_username": "tok-owner",
+            "email": "tok-owner",
+        }
+        assert get_current_owner_id(request) == "tok-owner"
+
+    @pytest.mark.unit
+    def test_session_takes_precedence_over_api_token_user(self):
+        """Session auth should take precedence over api_token_user in state."""
+        from app.utils.user_scope import get_current_owner_id
+
+        request = MagicMock()
+        request.session = {"user": {"sub": "session-sub", "email": "session@example.com"}}
+        request.state.api_token_user = {"id": "tok-owner"}
+        assert get_current_owner_id(request) == "session-sub"
+
+    @pytest.mark.unit
+    def test_resolves_bearer_token_directly(self, mu_engine, mu_session):
+        """get_current_owner_id should resolve a Bearer token when no session exists."""
+        from app.api.api_tokens import generate_api_token, hash_token
+        from app.utils.user_scope import get_current_owner_id
+
+        # Create a token in the DB
+        plaintext = generate_api_token()
+        token_hash = hash_token(plaintext)
+        db_token = ApiToken(
+            owner_id="bearer-owner",
+            name="Test Bearer",
+            token_hash=token_hash,
+            token_prefix=plaintext[:12],
+            is_active=True,
+        )
+        mu_session.add(db_token)
+        mu_session.commit()
+
+        # Build a mock request with Bearer header but no session
+        request = MagicMock()
+        request.session = {}
+        request.state = MagicMock(spec=[])  # no api_token_user attr
+        request.headers = {"authorization": f"Bearer {plaintext}"}
+        request.client.host = "127.0.0.1"
+
+        with patch("app.database.SessionLocal", return_value=mu_session):
+            # Prevent the session from being closed since it's shared with the test
+            mu_session.close = MagicMock()
+            result = get_current_owner_id(request)
+
+        assert result == "bearer-owner"
+        # Verify the resolved user was cached in request.state
+        assert request.state.api_token_user["id"] == "bearer-owner"
+
+    @pytest.mark.unit
+    def test_returns_none_for_invalid_bearer_token(self, mu_engine, mu_session):
+        """get_current_owner_id should return None for an invalid Bearer token."""
+        from app.utils.user_scope import get_current_owner_id
+
+        request = MagicMock()
+        request.session = {}
+        request.state = MagicMock(spec=[])  # no api_token_user attr
+        request.headers = {"authorization": "Bearer de_invalid_token_value"}
+        request.client.host = "127.0.0.1"
+
+        with patch("app.database.SessionLocal", return_value=mu_session):
+            mu_session.close = MagicMock()
+            result = get_current_owner_id(request)
+
+        assert result is None
+
+
+class TestOwnerIdFromUser:
+    """Tests for the _owner_id_from_user helper."""
+
+    @pytest.mark.unit
+    def test_prefers_sub(self):
+        from app.utils.user_scope import _owner_id_from_user
+
+        assert _owner_id_from_user({"sub": "s", "preferred_username": "u", "email": "e"}) == "s"
+
+    @pytest.mark.unit
+    def test_falls_back_to_preferred_username(self):
+        from app.utils.user_scope import _owner_id_from_user
+
+        assert _owner_id_from_user({"preferred_username": "u", "email": "e"}) == "u"
+
+    @pytest.mark.unit
+    def test_falls_back_to_email(self):
+        from app.utils.user_scope import _owner_id_from_user
+
+        assert _owner_id_from_user({"email": "e"}) == "e"
+
+    @pytest.mark.unit
+    def test_falls_back_to_id(self):
+        from app.utils.user_scope import _owner_id_from_user
+
+        assert _owner_id_from_user({"id": "i"}) == "i"
+
+    @pytest.mark.unit
+    def test_returns_none_for_empty_dict(self):
+        from app.utils.user_scope import _owner_id_from_user
+
+        assert _owner_id_from_user({}) is None
+
 
 class TestApplyOwnerFilter:
     """Tests for apply_owner_filter()."""