chore: replace print with logging and make robot conditional

All print statements in the main program, and components used by the main program, have been replaced with appropriate logging statements. The connection to the robot now only gets made when it's possible, otherwise only the microphone will be run.

ref: N25B-119

README.md

@@ -24,7 +24,13 @@ python -m virtualenv .venv
 source .venv/bin/activate
 ```
 
-Install the required packages with
+To be able to install the PyAudio Python package, you'll need to have the `portaudio` system package installed. On Debian or Ubuntu:
+
+```shell
+sudo apt install portaudio19-dev
+```
+
+Then you can install the required packages with
 
 ```bash
 pip install -r requirements.txt
@@ -59,7 +65,14 @@ python -c "import qi; print(qi)"
 You should now be able to run this project.
 
 ### MacOS
-...
+
+On ARM CPU's, pyenv doesn't want to install Python 2. You can download and install it from [the Python website](https://www.python.org/downloads/release/python-2718/).
+
+Create a virtual environment as described in the Linux section.
+
+Then build `portaudio` for x86_64 CPU's.
+
+Then follow the remaining installation instructions in the Linux section.
 
 ## Running
 Assuming you have the virtual environment activated (`source .venv/bin/activate` on Linux) and that you have a virtual robot running on localhost you should be able to run this project by typing

main.py

@@ -1,27 +1,69 @@
-import qi
+import sys
+import logging
+logging.
+
 import zmq
-import time
+
+from src.audio_streaming import AudioStreaming
+from state import state
 
 
 def say(session, message):
     tts = session.service("ALTextToSpeech")
     tts.say(message)
 
-if __name__ == "__main__":
-    app = qi.Application()
-    app.start()
-    session = app.session
 
+def listen_for_messages(session):
     context = zmq.Context()
     socket = context.socket(zmq.SUB)
     socket.connect("tcp://localhost:5556")
-    socket.setsockopt_string(zmq.SUBSCRIBE, u"") # u because Python 2 shenanigans
+    socket.setsockopt_string(zmq.SUBSCRIBE, u"")  # u because Python 2 shenanigans
 
-    while True:
-        print("Listening for message")
+    poller = zmq.Poller()
+    poller.register(socket, zmq.POLLIN)
+
+    logging.info("Listening for messages")
+    while not state.exit_event.is_set():
+        if not poller.poll(200): continue  # At most 200 ms delay after CTRL+C
+        # We now know there's a message waiting for us
         message = socket.recv_string()
-        print("Received message: {}".format(message))
+        logging.debug("Received message: {}".format(message))
 
-        say(session, message)
+        if session: say(session, message)
 
-        time.sleep(1)
+
+def get_session():
+    if "--qi-url" not in sys.argv:
+        logging.info("No Qi URL argument given. Running in stand-alone mode.")
+        return None
+
+    try:
+        import qi
+    except ImportError:
+        logging.info("Unable to import qi. Running in stand-alone mode.")
+        return None
+
+    try:
+        app = qi.Application()
+        app.start()
+        return app.session
+    except RuntimeError:
+        logging.info("Unable to connect to the robot. Running in stand-alone mode.")
+        return None
+
+
+def main():
+    session = get_session()
+
+    audio_streamer = AudioStreaming()
+    audio_streamer.run()
+
+    listen_for_messages(session)  # Runs indefinitely, until CTRL+C
+
+
+if __name__ == "__main__":
+    try:
+        state.initialize()
+        main()
+    finally:
+        state.deinitialize()

requirements.txt

@@ -1 +1,2 @@
-pyzmq<16
+pyzmq<16
+pyaudio<=0.2.11

src/audio_streaming.py

@@ -0,0 +1,93 @@
+import threading
+
+import pyaudio
+import zmq
+
+from state import state
+
+
+def choose_mic_interactive(audio):
+    """Choose a microphone to use. The `audio` parameter is an instance of PyAudio. Returns a dict."""
+    device_count = audio.get_device_count()
+    print("Found {} audio devices:".format(device_count))
+    for i in range(device_count):
+        print("- {}: {}".format(i, audio.get_device_info_by_index(i)["name"]))
+
+    microphone_index = None
+    while microphone_index is None:
+        chosen = input("Which device would you like to use?\n> ")
+        try:
+            chosen = int(chosen)
+            if chosen < 0 or chosen > device_count: raise ValueError()
+            microphone_index = chosen
+        except ValueError:
+            print("Please enter a number between 0 and {}".format(device_count))
+
+    chosen_microphone = audio.get_device_info_by_index(microphone_index)
+    print("Chose microphone \"{}\"".format(chosen_microphone["name"]))
+    return chosen_microphone
+
+
+def choose_mic_default(audio):
+    """Choose a microphone to use based on defaults. The `audio` parameter is a PyAudio. Returns a dict."""
+    default_device = audio.get_default_input_device_info()
+    return default_device
+
+
+class AudioStreaming:
+    def __init__(self, port=5557):
+        self.port = port
+        self.audio = pyaudio.PyAudio()
+        self.microphone = choose_mic_default(self.audio)
+        self.thread = None
+
+    def run(self):
+        self.thread = threading.Thread(target=self._stream)
+        self.thread.start()
+
+    def wait_until_done(self):
+        if not self.thread: return
+        self.thread.join()
+
+    def _stream(self):
+        context = zmq.Context()
+        socket = context.socket(zmq.PUB)
+        socket.bind("tcp://*:{}".format(self.port))
+
+        chunk = 512  # 320 at 16000 Hz is 20ms, 512 is required for Silero-VAD
+
+        stream = self.audio.open(
+            format=pyaudio.paFloat32,
+            channels=1,
+            rate=16000,
+            input=True,
+            input_device_index=self.microphone["index"],
+            frames_per_buffer=chunk,
+        )
+
+        try:
+            while not state.exit_event.is_set():
+                data = stream.read(chunk)
+                socket.send(data)
+        finally:
+            stream.stop_stream()
+            stream.close()
+
+
+if __name__ == "__main__":
+    state.initialize()
+    try:
+        audio = AudioStreaming()
+        print("Starting audio streaming...")
+        audio.run()
+
+        import time
+        end = time.time() + 10
+        while not state.exit_event.is_set() and time.time() < end:
+            print "\rExiting in {:.2f} seconds".format(end - time.time()),
+            time.sleep(0.05)
+
+        state.exit_event.set()
+        audio.wait_until_done()
+    finally:
+        state.deinitialize()

state.py

@@ -0,0 +1,53 @@
+import logging
+import signal
+import threading
+
+
+class State(object):
+    """
+    Do not create an instance of this class directly: use the instance `state` below. This state must be initiated once,
+    probably when your program starts.
+
+    This class is used to share state between threads. For example, when the program is quit, that all threads can
+    detect this via the `exit_event` property being set.
+    """
+    def __init__(self):
+        self.is_initialized = False
+        self.exit_event = None
+
+    def initialize(self):
+        if self.is_initialized:
+            logging.warn("Already initialized")
+            return
+
+        self.exit_event = threading.Event()
+        def handle_exit(_, __):
+            logging.info("Exiting.")
+            self.exit_event.set()
+        signal.signal(signal.SIGINT, handle_exit)
+        signal.signal(signal.SIGTERM, handle_exit)
+
+        self.is_initialized = True
+
+    def deinitialize(self):
+        if not self.is_initialized: return
+        self.is_initialized = False
+
+    def __getattribute__(self, name):
+        # Enforce that the state is initialized before accessing any property (aside from the basic ones)
+        if name in ("initialize", "deinitialize", "is_initialized", "__dict__", "__class__"):
+            return object.__getattribute__(self, name)
+
+        if not object.__getattribute__(self, "is_initialized"):
+            # Special case for the exit_event: if the event is set, return it without an error
+            if name == "exit_event":
+                exit_event = object.__getattribute__(self, "exit_event")
+                if exit_event and exit_event.is_set(): return exit_event
+
+            raise RuntimeError("State must be initialized before accessing '%s'" % name)
+
+        return object.__getattribute__(self, name)
+
+
+# Must call `.initialize` before use
+state = State()