[Tutor] call key on_press event multiple times when key is held down

[Carlton Banks]

I am trying to record from my microphone while i press down a button, problem is that the library I am using is not able to detect on hold event. It only detect on press, which happens once, which means that the microphone only records one sample..

import pyaudio
import wave
from pynput import keyboard

CHUNK = 8192
FORMAT = pyaudio.paInt16
CHANNELS = 2
RATE = 44100
RECORD_SECONDS = 5
WAVE_OUTPUT_FILENAME = "output.wav"

p = pyaudio.PyAudio()
stream = p.open(format=FORMAT,
                channels=CHANNELS,
                rate=RATE,
                input=True,
                frames_per_buffer=CHUNK)         
frames = []

def on_press(key):
    if key == keyboard.Key.cmd_l:
        print('- Started recording -'.format(key))
        try:
            data = stream.read(CHUNK)
            frames.append(data)
        except IOError: 
            print 'warning: dropped frame' # can replace with 'pass' if no message desired 
    else:
        print('incorrect character {0}, press cmd_l'.format(key))


def on_release(key):
    print('{0} released'.format(
        key))
    if key == keyboard.Key.cmd_l:
        print('{0} stop'.format(key))
        keyboard.Listener.stop
        return False

print("* recording")


with keyboard.Listener(on_press=on_press, on_release=on_release) as listener:
    listener.join()

print("* done recording")

stream.stop_stream()
stream.close()
p.terminate()

wf = wave.open(WAVE_OUTPUT_FILENAME, 'wb')
wf.setnchannels(CHANNELS)
wf.setsampwidth(p.get_sample_size(FORMAT))
wf.setframerate(RATE)
wf.writeframes(b''.join(frames))
wf.close()
I am using pynput <https://pypi.python.org/pypi/pynput> for keyboard events and pyaudio for recording. I am pretty sure that this should be the error, as the example script for recording, picks up samples in a for loop, which works. 

So does any of you know any libraries that monitors state of the keyboard, or any ideas on how to get this working?.. I tried with a while look inside the on_press callback but that resulted in me getting stuck that callback.


How can i fix this?