Use OAuth sessions for web API requests

add_links/api.py

@@ -85,14 +85,32 @@ webpage_error = (
 )
 
 
+def _get_request_oauth_session() -> requests.sessions.Session | None:
+    """Return the logged-in user's OAuth session in a Flask request, if present."""
+    try:
+        from flask import g, has_request_context
+
+        if not has_request_context():
+            return None
+
+        oauth_session = getattr(g, "oauth_session", None)
+        if oauth_session is not None:
+            return typing.cast(requests.sessions.Session, oauth_session)
+
+        from . import mediawiki_oauth
+
+        return typing.cast(
+            requests.sessions.Session | None, mediawiki_oauth.get_oauth_session()
+        )
+    except RuntimeError:
+        return None
+
+
 def _get_active_session() -> tuple[requests.sessions.Session, str]:
     """Return active session and auth mode."""
-    try:
-        from flask import g
-        if hasattr(g, "oauth_session") and g.oauth_session is not None:
-            return g.oauth_session, "oauth"  # type: ignore[return-value]
-    except RuntimeError:
-        pass
+    if oauth_session := _get_request_oauth_session():
+        return oauth_session, "oauth"
+
     print("WARNING: using unauthenticated session", file=sys.stderr)
     return get_session(), "anon"