feat: publish face detection instead of req/res

ref: N25B-395

src/robot_interface/core/config.py

@@ -19,6 +19,8 @@ class AgentSettings(object):
     :vartype audio_sender_port: int
     :ivar face_detection_port: Port used for sending face detection events, defaults to 5559.
     :vartype face_detection_port: int
+    :ivar face_detection_interval: Time between face detection events, defaults to 1000 ms.
+    :vartype face_detection_interval: int
     """
     def __init__(
         self,
@@ -28,6 +30,7 @@ class AgentSettings(object):
         video_sender_port=None,
         audio_sender_port=None,
         face_detection_port=None,
+        face_detection_interval=None,
     ):
         self.control_backend_host = get_config(control_backend_host, "AGENT__CONTROL_BACKEND_HOST", "localhost")
         self.actuation_receiver_port = get_config(actuation_receiver_port, "AGENT__ACTUATION_RECEIVER_PORT", 5557, int)
@@ -35,6 +38,7 @@ class AgentSettings(object):
         self.video_sender_port = get_config(video_sender_port, "AGENT__VIDEO_SENDER_PORT", 5556, int)
         self.audio_sender_port = get_config(audio_sender_port, "AGENT__AUDIO_SENDER_PORT", 5558, int)
         self.face_detection_port = get_config(face_detection_port, "AGENT__FACE_DETECTION_PORT", 5559, int)
+        self.face_detection_interval = get_config(face_detection_interval, "AGENT__FACE_DETECTION_INTERVAL", 1000, int)
 
 
 class VideoConfig(object):

src/robot_interface/endpoints/face_detector.py

@@ -13,61 +13,47 @@ from robot_interface.core.config import settings
 
 class FaceDetectionSender(SocketBase):
     """
-    Face detection REP endpoint.
+    Face detection endpoint.
 
-    - Polls ALMemory["FaceDetected"]
-    - Maintains a rolling boolean state
-    - Responds to REQ polling over ZMQ REP
+    Subscribes to and polls ALMemory["FaceDetected"], sends events to CB.
     """
 
     def __init__(self, zmq_context, port=settings.agent_settings.face_detection_port):
         super(FaceDetectionSender, self).__init__("face")
 
-        if port:
-            self.create_socket(zmq_context, zmq.REP, port)
+        self.create_socket(zmq_context, zmq.PUB, port)
 
         self._face_service = None
         self._memory_service = None
 
-        self.face_detected = False
-        self._last_seen_face_time = 0
-
         self._face_thread = None
-        self._rep_thread = None
-
-    def endpoint_description(self):
-        return "face"
-
-    # ------------------------------------------------------------------
-    # Face detection logic (runs independently)
-    # ------------------------------------------------------------------
 
     def start_face_detection(self):
         if not state.qi_session:
             logging.warning("No Qi session available. Face detection not started.")
             return
 
-        import qi
-
         self._face_service = state.qi_session.service("ALFaceDetection")
         self._memory_service = state.qi_session.service("ALMemory")
 
         self._face_service.setTrackingEnabled(False)
         self._face_service.setRecognitionEnabled(False)
 
-        self._face_service.subscribe("FaceDetectionSender", 500, 0.0)
+        self._face_service.subscribe(
+            "FaceDetectionSender",
+            settings.agent_settings.face_detection_interval,
+            0.0,
+        )
 
         self._face_thread = threading.Thread(target=self._face_loop)
         self._face_thread.start()
 
-        self._rep_thread = threading.Thread(target=self._rep_loop)
-        self._rep_thread.start()
-
-        logging.info("Face detection + REP endpoint started.")
+        logging.info("Face detection started.")
 
     def _face_loop(self):
         """
-        Continuously updates `self.face_detected`.
+        Continuously send face detected to the CB, at the interval set in the
+        ``start_face_detection`` method.
         """
         while not state.exit_event.is_set():
             try:
@@ -81,40 +67,11 @@ class FaceDetectionSender(SocketBase):
                     and len(value[1][0]) > 0
                 )
 
-                now = time.time()
-                if face_present:
-                    self._last_seen_face_time = now
-
-                # Face considered lost after 3 seconds
-                self.face_detected = (now - self._last_seen_face_time) < 3
-
+                self.socket.send(json.dumps({"face_detected": face_present}).encode("utf-8"))
             except Exception:
                 logging.exception("Error reading FaceDetected")
 
-            time.sleep(0.1)
-
-
-    def _rep_loop(self):
-        """
-        Handles ZMQ REQ/REP polling from the Control Backend.
-        """
-        while not state.exit_event.is_set():
-            try:
-                # Receive request (content ignored)
-                _ = self.socket.recv()
-
-                # Respond with current face state
-                response = {
-                    "endpoint": "face",
-                    "data": self.face_detected,
-                }
-
-                self.socket.send_json(response)
-
-            except Exception:
-                logging.exception("Error in face detection REP loop")
-                time.sleep(0.1)
-
+            time.sleep(settings.agent_settings.face_detection_interval / 1000.0)
 
     def stop_face_detection(self):
         try:
@@ -124,3 +81,7 @@ class FaceDetectionSender(SocketBase):
             logging.info("Face detection stopped.")
         except Exception:
             logging.warning("Error during face detection cleanup.")
+
+    def close(self):
+        super(FaceDetectionSender, self).close()
+        self.stop_face_detection()