Cache TB data: backend/api/routes/control.py

backend/api/routes/control.py

@@ -61,14 +61,23 @@ async def control_budget():
     )
 
 
+_tracker_cache: dict = {"data": None, "expires": 0.0}
+
+
 @router.get("/trackers")
 async def control_trackers():
-    """Live tracker angles from ThingsBoard."""
+    """Live tracker angles from ThingsBoard (5-min TTL cache)."""
+    import time as _time
+    if _tracker_cache["data"] and _time.monotonic() < _tracker_cache["expires"]:
+        return _tracker_cache["data"]
     try:
         from src.tracker_dispatcher import TrackerDispatcher
         dispatcher = TrackerDispatcher()
         angles = dispatcher.read_current_angles()
-        return {"trackers": angles, "source": "ThingsBoard"}
+        result = {"trackers": angles, "source": "ThingsBoard"}
+        _tracker_cache["data"] = result
+        _tracker_cache["expires"] = _time.monotonic() + 300  # 5 min
+        return result
     except Exception as exc:
         log.error("Tracker fetch failed: %s", exc)
         raise HTTPException(status_code=502, detail=f"Tracker fetch failed: {exc}")