chore: forgot copyright

ref: N25B-397

src/robot_interface/core/config.py

@@ -17,6 +17,10 @@ class AgentSettings(object):
     :vartype video_sender_port: int
     :ivar audio_sender_port: Port used for sending audio data, defaults to 5558.
     :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,
@@ -25,12 +29,16 @@ class AgentSettings(object):
         main_receiver_port=None,
         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)
         self.main_receiver_port = get_config(main_receiver_port, "AGENT__MAIN_RECEIVER_PORT", 5555, int)
         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/actuation_receiver.py

@@ -1,11 +1,12 @@
 from __future__ import unicode_literals  # So that we can log texts with Unicode characters
 import logging
+from threading import Thread
 
+import Queue
 import zmq
 
 from robot_interface.endpoints.receiver_base import ReceiverBase
 from robot_interface.state import state
-
 from robot_interface.core.config import settings
 from robot_interface.endpoints.gesture_settings import GestureTags
 
@@ -32,6 +33,9 @@ class ActuationReceiver(ReceiverBase):
         self.socket.setsockopt_string(zmq.SUBSCRIBE, u"")  # Causes block if given in options
         self._tts_service = None
         self._animation_service = None
+        self._message_queue = Queue.Queue()
+        self.message_thread = Thread(target=self._handle_messages)
+        self.message_thread.start()
 
     def _handle_speech(self, message):
         """
@@ -58,8 +62,26 @@ class ActuationReceiver(ReceiverBase):
         if not self._tts_service:
             self._tts_service = state.qi_session.service("ALTextToSpeech")
 
-        # Returns instantly. Messages received while speaking will be queued.
+        if message.get("is_priority"):
-        getattr(qi, "async")(self._tts_service.say, text)
+            # Bypass queue and speak immediately
+            self.clear_queue()
+            self._message_queue.put(text)
+            logging.debug("Force speaking immediately: {}".format(text))
+        else: 
+            self._message_queue.put(text)
+
+    def clear_queue(self):
+        """
+        Safely drains all pending messages from the queue.
+        """
+        logging.info("Message queue size: {}".format(self._message_queue.qsize()))
+        try:
+            while True:
+                # Remove items one by one without waiting
+                self._message_queue.get_nowait()
+        except Queue.Empty:
+            pass
+        logging.info("Message queue cleared.")
 
     def _handle_gesture(self, message, is_single):
         """
@@ -122,6 +144,19 @@ class ActuationReceiver(ReceiverBase):
         if message["endpoint"] == "actuate/gesture/single":
             self._handle_gesture(message, True)
 
+    def _handle_messages(self):
+        while not state.exit_event.is_set():
+            try:
+                text = self._message_queue.get(timeout=0.1)
+                state.is_speaking = True
+                self._tts_service.say(text)
+            except Queue.Empty:
+                state.is_speaking = False
+            except RuntimeError:
+                logging.error("Lost connection to Pepper. Please check if you're connected to the "
+                              "local WiFi and restart this application.")
+                state.exit_event.set()        
+
     def endpoint_description(self):
         """
         Extend the default endpoint description with gesture tags.

src/robot_interface/endpoints/audio_sender.py

@@ -89,6 +89,7 @@ class AudioSender(SocketBase):
         try:
             while not state.exit_event.is_set():
                 data = stream.read(chunk)
+                if (state.is_speaking): continue  # Do not send audio while the robot is speaking
                 self.socket.send(data)
         except IOError as e:
             logger.error("Stopped listening: failed to get audio from microphone.", exc_info=e)

src/robot_interface/endpoints/face_detector.py

@@ -0,0 +1,93 @@
+# -*- coding: utf-8 -*-
+"""
+This program has been developed by students from the bachelor Computer Science at Utrecht
+University within the Software Project course.
+© Copyright Utrecht University (Department of Information and Computing Sciences)
+"""
+from __future__ import unicode_literals
+
+import json
+import logging
+import threading
+import time
+import zmq
+
+from robot_interface.endpoints.socket_base import SocketBase
+from robot_interface.state import state
+from robot_interface.core.config import settings
+
+
+class FaceDetectionSender(SocketBase):
+    """
+    Face detection endpoint.
+
+    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")
+
+        self.create_socket(zmq_context, zmq.PUB, port)
+
+        self._face_service = None
+        self._memory_service = None
+
+        self._face_thread = None
+
+    def start_face_detection(self):
+        if not state.qi_session:
+            logging.warning("No Qi session available. Face detection not started.")
+            return
+
+        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",
+            settings.agent_settings.face_detection_interval,
+            0.0,
+        )
+
+        self._face_thread = threading.Thread(target=self._face_loop)
+        self._face_thread.start()
+
+        logging.info("Face detection started.")
+
+    def _face_loop(self):
+        """
+        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:
+                value = self._memory_service.getData("FaceDetected", 0)
+
+                face_present = (
+                    value
+                    and len(value) > 1
+                    and value[1]
+                    and value[1][0]
+                    and len(value[1][0]) > 0
+                )
+
+                self.socket.send(json.dumps({"face_detected": face_present}).encode("utf-8"))
+            except Exception:
+                logging.exception("Error reading FaceDetected")
+
+            time.sleep(settings.agent_settings.face_detection_interval / 1000.0)
+
+    def stop_face_detection(self):
+        try:
+            if self._face_service:
+                self._face_service.unsubscribe("FaceDetectionSender")
+                self._face_service.setTrackingEnabled(False)
+            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()

src/robot_interface/endpoints/main_receiver.py

@@ -4,6 +4,7 @@ from robot_interface.endpoints.receiver_base import ReceiverBase
 from robot_interface.state import state
 
 from robot_interface.core.config import settings
+from robot_interface.endpoints.face_detector import FaceDetectionSender
 
 
 class MainReceiver(ReceiverBase):
@@ -37,6 +38,7 @@ class MainReceiver(ReceiverBase):
         """
         return {"endpoint": "ping", "data": message.get("data")}
 
+
     @staticmethod
     def _handle_port_negotiation(message):
         """

src/robot_interface/endpoints/video_sender.py

@@ -6,6 +6,7 @@ from robot_interface.endpoints.socket_base import SocketBase
 from robot_interface.state import state
 from robot_interface.core.config import settings
 
+
 class VideoSender(SocketBase):
     """
     Video sender endpoint, responsible for sending video frames.

src/robot_interface/main.py

@@ -12,6 +12,8 @@ from robot_interface.endpoints.video_sender import VideoSender
 from robot_interface.state import state
 from robot_interface.core.config import settings
 from robot_interface.utils.timeblock import TimeBlock
+from robot_interface.endpoints.face_detector import FaceDetectionSender
+
 
 
 def main_loop(context):
@@ -35,6 +37,12 @@ def main_loop(context):
     video_sender.start_video_rcv()
     audio_sender.start()
 
+    # --- Face detection sender ---
+    face_sender = FaceDetectionSender(context)
+    state.sockets.append(face_sender)
+    face_sender.start_face_detection()
+
+
     # Sockets that can run on the main thread. These sockets' endpoints should not block for long (say 50 ms at most).
     receivers = [main_receiver, actuation_receiver]
 

src/robot_interface/state.py

@@ -30,6 +30,7 @@ class State(object):
         self.exit_event = None
         self.sockets = []  
         self.qi_session = None 
+        self.is_speaking = False
 
     def initialize(self):
         """

test/conftest.py

@@ -0,0 +1,10 @@
+from mock import patch, MagicMock
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def mock_zmq_context():
+    with patch("zmq.Context") as mock:
+        mock.instance.return_value = MagicMock()
+        yield mock

test/unit/test_actuation_receiver.py

@@ -20,46 +20,109 @@ def zmq_context():
     yield context
 
 
-def test_handle_unimplemented_endpoint(zmq_context):
+def test_force_speech_clears_queue(mocker):
     """
-    Tests that the ``ActuationReceiver.handle_message`` method can
+    Tests that a force speech message clears the existing queue
-    handle an unknown or unimplemented endpoint without raising an error.
+    and places the high-priority message at the front.
     """
-    receiver = ActuationReceiver(zmq_context)
+    mocker.patch("threading.Thread")
-    # Should not error
+    mock_state = mocker.patch("robot_interface.endpoints.actuation_receiver.state")
+    
+    mock_qi = mock.Mock()
+    sys.modules["qi"] = mock_qi 
+
+    mock_tts_service = mock.Mock()
+    mock_state.qi_session.service.return_value = mock_tts_service
+
+    # Use Mock Context
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    
+    receiver._message_queue.put("old_message_1")
+    receiver._message_queue.put("old_message_2")
+    
+    assert receiver._message_queue.qsize() == 2
+
+    force_msg = {
+        "endpoint": "actuate/speech", 
+        "data": "Emergency Notification",
+        "is_priority": True,
+    }
+    receiver.handle_message(force_msg)
+
+    assert receiver._message_queue.qsize() == 1
+    queued_item = receiver._message_queue.get()
+    assert queued_item == "Emergency Notification"
+
+
+def test_handle_unimplemented_endpoint(mocker):
+    """
+    Tests handling of unknown endpoints.
+    """
+    mocker.patch("threading.Thread")
+    
+    # Use Mock Context
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    
     receiver.handle_message({
         "endpoint": "some_endpoint_that_definitely_does_not_exist",
         "data": None,
     })
 
 
-def test_speech_message_no_data(zmq_context, mocker):
+def test_speech_message_no_data(mocker):
     """
-    Tests that the message handler logs a warning when a speech actuation
+    Tests that if the message data is empty, the receiver returns immediately
-    request (`actuate/speech`) is received but contains empty string data.
+    WITHOUT attempting to access the global robot state or session.
     """
-    mock_warn = mocker.patch("logging.warn")
+    # 1. Prevent background threads from running
+    mocker.patch("threading.Thread")
+    
+    # 2. Mock the global state object
+    mock_state = mocker.patch("robot_interface.endpoints.actuation_receiver.state")
 
-    receiver = ActuationReceiver(zmq_context)
+    # 3. Create a PropertyMock to track whenever 'qi_session' is accessed
+    # We attach it to the class type of the mock so it acts like a real property
+    mock_session_prop = mock.PropertyMock(return_value=None)
+    type(mock_state).qi_session = mock_session_prop
+
+    # 4. Initialize Receiver (Mocking the context to avoid ZMQ errors)
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    
+    # 5. Send empty data
     receiver.handle_message({"endpoint": "actuate/speech", "data": ""})
 
-    mock_warn.assert_called_with(mock.ANY)
+    # 6. Assertion: 
+    # Because the code does `if not text: return` BEFORE `if not state.qi_session`,
+    # the state property should NEVER be read.
+    mock_session_prop.assert_not_called()
 
 
-def test_speech_message_invalid_data(zmq_context, mocker):
+def test_speech_message_invalid_data(mocker):
     """
-    Tests that the message handler logs a warning when a speech actuation
+    Tests that if the message data is not a string, the function returns.     
-    request (`actuate/speech`) is received with data that is not a string (e.g., a boolean).
+    :param mocker: Description
     """
-    mock_warn = mocker.patch("logging.warn")
+    mocker.patch("threading.Thread")
 
-    receiver = ActuationReceiver(zmq_context)
+    mock_state = mocker.patch("robot_interface.endpoints.actuation_receiver.state")
+
+    mock_session_prop = mock.PropertyMock(return_value=None)
+    type(mock_state).qi_session = mock_session_prop
+
+    # Use Mock Context
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    
     receiver.handle_message({"endpoint": "actuate/speech", "data": True})
 
-    mock_warn.assert_called_with(mock.ANY)
+    # Because the code does `if not text: return` BEFORE `if not state.qi_session`,
+    # the state property should NEVER be read.
+    mock_session_prop.assert_not_called()
 
-
+def test_speech_no_qi(mocker):
-def test_speech_no_qi(zmq_context, mocker):
     """
     Tests the actuation receiver's behavior when processing a speech request
     but the global state does not have an active QI session.
@@ -69,16 +132,21 @@ def test_speech_no_qi(zmq_context, mocker):
     mock_qi_session = mock.PropertyMock(return_value=None)
     type(mock_state).qi_session = mock_qi_session
 
-    receiver = ActuationReceiver(zmq_context)
+    mock_tts_service = mock.Mock()
+
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    receiver._tts_service = mock_tts_service
+
     receiver._handle_speech({"endpoint": "actuate/speech", "data": "Some message to speak."})
 
-    mock_qi_session.assert_called()
+    receiver._tts_service.assert_not_called()
 
 
-def test_speech(zmq_context, mocker):
+def test_speech(mocker):
     """
     Tests the core speech actuation functionality by mocking the QI TextToSpeech
-    service and verifying that it is called correctly.
+    service and verifying that the received message is put into the queue.
     """
     mock_state = mocker.patch("robot_interface.endpoints.actuation_receiver.state")
 
@@ -89,17 +157,182 @@ def test_speech(zmq_context, mocker):
     mock_state.qi_session = mock.Mock()
     mock_state.qi_session.service.return_value = mock_tts_service
 
-    receiver = ActuationReceiver(zmq_context)
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+
     receiver._tts_service = None
     receiver._handle_speech({"endpoint": "actuate/speech", "data": "Some message to speak."})
 
-    mock_state.qi_session.service.assert_called_once_with("ALTextToSpeech")
+    assert receiver._message_queue.qsize() == 1
 
-    getattr(mock_qi, "async").assert_called_once()
+    queued_item = receiver._message_queue.get()
-    call_args = getattr(mock_qi, "async").call_args[0]
+    assert queued_item == "Some message to speak."
-    assert call_args[0] == mock_tts_service.say
-    assert call_args[1] == "Some message to speak."
 
+def test_speech_priority(mocker):
+    """
+    Tests that a priority speech message is handled correctly by clearing the queue
+    and placing the priority message at the front.
+    """
+    mock_state = mocker.patch("robot_interface.endpoints.actuation_receiver.state")
+
+    mock_qi = mock.Mock()
+    sys.modules["qi"] = mock_qi
+
+    mock_tts_service = mock.Mock()
+    mock_state.qi_session = mock.Mock()
+    mock_state.qi_session.service.return_value = mock_tts_service
+
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+
+    receiver._message_queue.put("old_message_1")
+    receiver._message_queue.put("old_message_2")
+
+    assert receiver._message_queue.qsize() == 2
+
+    priority_msg = {
+        "endpoint": "actuate/speech", 
+        "data": "Urgent Message",
+        "is_priority": True,
+    }
+    receiver._handle_speech(priority_msg)
+
+    assert receiver._message_queue.qsize() == 1
+    queued_item = receiver._message_queue.get()
+    assert queued_item == "Urgent Message"
+
+def test_handle_messages_loop(mocker):
+    """
+    Tests the background consumer loop (_handle_messages) processing an item.
+    Runs SYNCHRONOUSLY to ensure coverage tools pick up the lines.
+    """
+    # Patch Thread so the real background thread NEVER starts automatically
+    mocker.patch("threading.Thread")
+
+    # Mock state
+    mock_state = mocker.patch("robot_interface.endpoints.actuation_receiver.state")
+        
+    # Setup initial speaking state to False (covers "Started speaking" print)
+    mock_state.is_speaking = False
+    
+    # Mock the TextToSpeech service
+    mock_tts_service = mock.Mock()
+    mock_state.qi_session.service.return_value = mock_tts_service
+    
+    # Initialize receiver (Thread is patched, so no thread starts)
+    # Use Mock Context to avoid ZMQ errors
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    
+    # Manually inject service (since lazy loading might handle it, but this is safer)
+    receiver._tts_service = mock_tts_service
+
+    # This ensures the while loop iterates exactly once
+    mock_state.exit_event.is_set.side_effect = [False, True]
+
+    # Put an item in the queue
+    receiver._message_queue.put("Hello World")
+
+    # RUN MANUALLY in the main thread
+    # This executes the code: while -> try -> get -> if print -> speaking=True -> say
+    receiver._handle_messages()
+
+    # Assertions
+    assert receiver._message_queue.empty()
+    mock_tts_service.say.assert_called_with("Hello World")
+    assert mock_state.is_speaking is True
+
+
+def test_handle_messages_queue_empty(mocker):
+    """
+    Tests the Queue.Empty exception handler in the consumer loop.
+    This covers the logic that resets 'state.is_speaking' to False.
+    """
+    # Prevent the real background thread from starting
+    mocker.patch("threading.Thread")
+
+    # Mock the state object
+    mock_state = mocker.patch("robot_interface.endpoints.actuation_receiver.state")
+        
+    # Setup 'is_speaking' property mock
+    # We set return_value=True so the code enters the 'if state.is_speaking:' block.
+    # We use PropertyMock to track when this attribute is set.
+    type(mock_state).is_speaking = True
+    
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    
+    # This ensures the while loop body runs exactly once for our test
+    mock_state.exit_event.is_set.side_effect = [False, True]
+
+    # Force get() to raise Queue.Empty immediately (simulate timeout)
+    # We patch the 'get' method on the specific queue instance of our receiver
+    #mocker.patch.object(receiver._message_queue, 'get', side_effect=Queue.Empty)
+    
+    # Run the loop logic manually (synchronously)
+    receiver._handle_messages()
+
+    # Final Assertion: Verify is_speaking was set to False
+    # The code execution order is: read (returns True) -> print -> set (to False)
+    # assert_called_with checks the arguments of the LAST call, which is the setter.
+    assert mock_state.is_speaking is False
+
+
+def test_handle_messages_runtime_error(mocker):
+    """
+    Tests the RuntimeError exception handler (e.g. lost WiFi connection).
+    Uses a Mock ZMQ context to avoid 'Address already in use' errors.
+    """
+    # Patch Thread so we don't accidentally spawn real threads
+    mocker.patch("threading.Thread")
+    
+    # Mock the state and logging
+    mock_state = mocker.patch("robot_interface.endpoints.actuation_receiver.state")
+        
+    # Use a MOCK ZMQ context. 
+    # This prevents the receiver from trying to bind to a real TCP port.
+    mock_zmq_ctx = mock.Mock()
+    
+    # Initialize receiver with the mock context
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    
+    mock_state.exit_event.is_set.side_effect = [False, True]
+
+    receiver._message_queue.put("Test Message")
+    
+    # Setup: ...BUT the service raises RuntimeError when asked to speak
+    mock_tts = mock.Mock()
+    mock_tts.say.side_effect = RuntimeError("Connection lost")
+    receiver._tts_service = mock_tts
+    
+    # Run the loop logic manually
+    receiver._handle_messages()
+    
+    # Assertions
+    assert mock_state.exit_event.is_set.called
+
+def test_clear_queue(mocker):
+    """
+    Tests that the clear_queue method properly drains all items from the message queue.
+    """
+    mocker.patch("threading.Thread")
+    
+    # Use Mock Context
+    mock_zmq_ctx = mock.Mock()
+    receiver = ActuationReceiver(mock_zmq_ctx)
+    
+    # Populate the queue with multiple items
+    receiver._message_queue.put("msg1")
+    receiver._message_queue.put("msg2")
+    receiver._message_queue.put("msg3")
+    
+    assert receiver._message_queue.qsize() == 3
+
+    # Clear the queue
+    receiver.clear_queue()
+
+    # Assert the queue is empty
+    assert receiver._message_queue.qsize() == 0
 
 def test_gesture_no_data(zmq_context, mocker):
     receiver = ActuationReceiver(zmq_context)

test/unit/test_audio_sender.py

@@ -77,7 +77,8 @@ def test_sending_audio(mocker):
 
     mock_zmq_context = mock.Mock()
     send_socket = mock.Mock()
-
+    
+    mock_state.is_speaking = False
     # If there's something wrong with the microphone, it will raise an IOError when `read`ing.
     stream = mock.Mock()
     stream.read = _fake_read
@@ -93,6 +94,36 @@ def test_sending_audio(mocker):
     send_socket.assert_called()
 
 
+def test_no_sending_if_speaking(mocker):
+    """
+    Tests the successful sending of audio data over a ZeroMQ socket.
+    """
+    mock_choose_mic = mocker.patch("robot_interface.endpoints.audio_sender.choose_mic")
+    mock_choose_mic.return_value = {"name": u"Some mic", "index": 0L}
+
+    mock_state = mocker.patch("robot_interface.endpoints.audio_sender.state")
+    mock_state.exit_event.is_set.side_effect = [False, True]
+
+    mock_zmq_context = mock.Mock()
+    send_socket = mock.Mock()
+    
+    mock_state.is_speaking = True
+
+    # If there's something wrong with the microphone, it will raise an IOError when `read`ing.
+    stream = mock.Mock()
+    stream.read = _fake_read
+
+    sender = AudioSender(mock_zmq_context)
+    sender.socket.send = send_socket
+    sender.audio.open = mock.Mock()
+    sender.audio.open.return_value = stream
+
+    sender.start()
+    sender.wait_until_done()
+
+    send_socket.assert_not_called()
+
+
 def _fake_read_error(num_frames):
     """
     Helper function to simulate an I/O error during microphone stream reading.

test/unit/test_face_detection_sender.py

@@ -0,0 +1,175 @@
+# -*- coding: utf-8 -*-
+"""
+This program has been developed by students from the bachelor Computer Science at Utrecht
+University within the Software Project course.
+© Copyright Utrecht University (Department of Information and Computing Sciences)
+"""
+from __future__ import unicode_literals
+
+import json
+import mock
+import pytest
+
+from robot_interface.endpoints.face_detector import FaceDetectionSender
+from robot_interface.state import state
+
+
+@pytest.fixture(autouse=True)
+def initialized_state(monkeypatch):
+    """
+    Fully initialize global state so __getattribute__ allows access.
+    """
+    # Bypass the initialization guard
+    monkeypatch.setattr(state, "is_initialized", True, raising=False)
+
+    # Install a controllable exit_event
+    exit_event = mock.Mock()
+    exit_event.is_set = mock.Mock(return_value=True)
+    monkeypatch.setattr(state, "exit_event", exit_event, raising=False)
+
+    # Default qi_session is None unless overridden
+    monkeypatch.setattr(state, "qi_session", None, raising=False)
+
+    yield
+
+
+def test_start_face_detection_no_qi_session():
+    """
+    Returns early when qi_session is None.
+    """
+    sender = FaceDetectionSender(mock.Mock())
+    sender.start_face_detection()
+
+    assert sender._face_thread is None
+    assert sender._face_service is None
+    assert sender._memory_service is None
+
+
+def test_start_face_detection_happy_path(mocker):
+    """
+    Initializes services and starts background thread.
+    """
+    mock_face = mock.Mock()
+    mock_memory = mock.Mock()
+
+    mock_qi = mock.Mock()
+    mock_qi.service.side_effect = lambda name: {
+        "ALFaceDetection": mock_face,
+        "ALMemory": mock_memory,
+    }[name]
+
+    state.qi_session = mock_qi
+
+    fake_thread = mock.Mock()
+    mocker.patch("threading.Thread", return_value=fake_thread)
+
+    sender = FaceDetectionSender(mock.Mock())
+    sender.start_face_detection()
+
+    mock_face.setTrackingEnabled.assert_called_with(False)
+    mock_face.setRecognitionEnabled.assert_called_with(False)
+    mock_face.subscribe.assert_called_once()
+    fake_thread.start.assert_called_once()
+
+
+def test_face_loop_face_detected_true(mocker):
+    """
+    Sends face_detected=True when face data exists.
+    """
+    sender = FaceDetectionSender(mock.Mock())
+
+    sender._memory_service = mock.Mock()
+    sender._memory_service.getData.return_value = [0, [[1]]]
+    sender.socket = mock.Mock()
+
+    mocker.patch("time.sleep")
+    state.exit_event.is_set.side_effect = [False, True]
+
+    sender._face_loop()
+
+    sent = sender.socket.send.call_args[0][0]
+    payload = json.loads(sent.decode("utf-8"))
+
+    assert payload["face_detected"] is True
+
+
+def test_face_loop_face_detected_false(mocker):
+    """
+    Sends face_detected=False when no face data exists.
+    """
+    sender = FaceDetectionSender(mock.Mock())
+
+    sender._memory_service = mock.Mock()
+    sender._memory_service.getData.return_value = []
+    sender.socket = mock.Mock()
+
+    mocker.patch("time.sleep")
+    state.exit_event.is_set.side_effect = [False, True]
+
+    sender._face_loop()
+
+    sent = sender.socket.send.call_args[0][0]
+    payload = json.loads(sent.decode("utf-8"))
+
+    assert not payload["face_detected"]
+
+
+def test_face_loop_handles_exception(mocker):
+    """
+    Exceptions inside loop are swallowed.
+    """
+    sender = FaceDetectionSender(mock.Mock())
+
+    sender._memory_service = mock.Mock()
+    sender._memory_service.getData.side_effect = Exception("boom")
+    sender.socket = mock.Mock()
+
+    mocker.patch("time.sleep")
+    state.exit_event.is_set.side_effect = [False, True]
+
+    # Must not raise
+    sender._face_loop()
+
+
+def test_stop_face_detection_happy_path():
+    """
+    Unsubscribes and disables tracking.
+    """
+    sender = FaceDetectionSender(mock.Mock())
+
+    mock_face = mock.Mock()
+    sender._face_service = mock_face
+
+    sender.stop_face_detection()
+
+    mock_face.unsubscribe.assert_called_once()
+    mock_face.setTrackingEnabled.assert_called_with(False)
+
+
+def test_stop_face_detection_exception():
+    """
+    stop_face_detection swallows service exceptions.
+    """
+    sender = FaceDetectionSender(mock.Mock())
+
+    mock_face = mock.Mock()
+    mock_face.unsubscribe.side_effect = Exception("fail")
+    sender._face_service = mock_face
+
+    sender.stop_face_detection()
+
+
+def test_close_calls_stop_face_detection(mocker):
+    """
+    close() calls parent close and stop_face_detection().
+    """
+    sender = FaceDetectionSender(mock.Mock())
+
+    mocker.patch.object(sender, "stop_face_detection")
+    mocker.patch(
+        "robot_interface.endpoints.face_detector.SocketBase.close"
+    )
+
+    sender.close()
+
+    sender.stop_face_detection.assert_called_once()

test/unit/test_main.py

@@ -55,6 +55,9 @@ class DummySender:
     def start(self):
         self.called = True
 
+    def start_face_detection(self):
+        self.called = True
+
     def close(self):
         pass
 
@@ -108,11 +111,13 @@ def patched_main_components(monkeypatch, fake_sockets, fake_poll):
     fake_act = FakeReceiver(act_sock)
     video_sender = DummySender()
     audio_sender = DummySender()
+    face_sender = DummySender()
 
     monkeypatch.setattr(main_mod, "MainReceiver", lambda ctx: fake_main)
     monkeypatch.setattr(main_mod, "ActuationReceiver", lambda ctx: fake_act)
     monkeypatch.setattr(main_mod, "VideoSender", lambda ctx: video_sender)
     monkeypatch.setattr(main_mod, "AudioSender", lambda ctx: audio_sender)
+    monkeypatch.setattr(main_mod, "FaceDetectionSender", lambda ctx: face_sender)
 
     # Register sockets for the fake poller
     fake_poll.registered = {main_sock: zmq.POLLIN, act_sock: zmq.POLLIN}