PropertyListener
The panel does not poll HTTP. It opens a WebSocket to:
ws://<fgfs-host>/PropertyListener
…where <fgfs-host> is whatever you pass as the fgfs query parameter (e.g. 127.0.0.1:8080).
The @openattitude/core store sends listener commands for each subscribed property. The composable useFgPanelPropertyBindings (in the panel repo) registers the paths used by the Seneca II layout, including:
- Attitude, airspeed (IAS/TAS disk), altimeter, VSI, turn coordinator, slip/skid
- KCS55 / KI525 HSI and related nav validity flags
- KI209 (NAV1) OBS, CDI, glideslope, to/from flags
- ADF bearing and card rotation
- GPS latitude, longitude, heading, zoom
- Engine RPM, manifold, fuel flow, EGT, gyro suction, flap and trim
- Clock UTC day-seconds
Exact path strings live in the panel source; adjust there if your aircraft uses different nodes.
Security and networks
Treat the PropertyListener port like debug access to sim state. Use localhost or a trusted LAN; do not expose an unauthenticated listener to the public internet without additional controls.
FlightGear side
Enable the generic WebSocket PropertyListener for the host/port you configure. Consult current FlightGear documentation for the exact property and startup flags for your version.