Sequential recording with Audacity with Python.

record_parts.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

"""
Record Parts:
=============

A demonstration Python application controlling Audacity to make a
sequence of recordings. There will inevitably be short breaks between
each recording due to the time required to Export, clean up and start
the next recording.

Before running this script, ensure that Audacity is running and
mod-script-pipe is enabled.
"""

import sys
from time import sleep
from pathlib import Path
from os import remove

import pipeclient as pc


def config_ext() -> str:
    """Return project file extension."""
    extensions: tuple = ('wav', 'mp3', 'ogg', 'flac')
    while True:
        ext: str = input('Export file type (wav, mp3, ogg, flac): ')
        if ext in extensions:
            return ext
        print('Enter wav, mp3, ogg, or flac')


def config_fname(ext) -> str:
    """Return base file name."""
    while True:
        fname: str = input('Root name for projects: ')
        print(f'Projects will be named {fname}1.{ext}, {fname}2.{ext}, ...')
        reponse = input('Use this project name? Y/N: ')
        if reponse.lower() == 'y':
            return fname


def config_fpath(fname: str, ext: str) -> Path:
    """Return output  directory"""
    while True:
        path = Path(input('Output directory: ')).expanduser()
        try:
            path.mkdir(parents=True, exist_ok=False)
        except FileExistsError:
            reponse = input(f'{path} already exists. Use this path? Y/N: ')
            if reponse.lower() != 'y':
                continue
        except PermissionError:
            print(f'{path} is not writeable. Try again.')
            continue
        try:
            path.joinpath(f'{fname}.{ext}').touch()
            remove(path.joinpath(f'{fname}.{ext}'))
        except PermissionError:
            print(f'{path} is not writeable. Try again.')
            continue
        print(f'Output folder is: {path}')
        return path


def config_recordings() -> tuple:
    """Return tuple(dur, number)
    dur is the duration of each recording in seconds.
    number is the number of recordings to make.
    """
    while True:
        response: str = input('Length of each recording in minutes: ')
        try:
            dur: float = float(response) * 60
        except ValueError:
            print(f'"{response}" is not a number.')
            continue
        response = input('Number of recordings: ')
        try:
            number: int = int(response)
        except ValueError:
            print(f'"{response}" is not a whole number.')
            continue
        return (dur, number)


def main(params: dict):
    """Loop through commands to record and export recordings."""
    client = pc.PipeClient()
    client.write('GetPreference: Name="AudioIO/RecordChannels"')
    # Wait for the response:
    while not(chans := client.read()):
        sleep(0.01)
    # print('Chans:', chans)
    for idx in range(1, params['rcount'] + 1):
        filename = params['fpath'].joinpath(
                f'{params["fname"]}{idx}.{params["ext"]}'
                )
        client.write(f'SelectTime: Start=0 End={params["duration"]}')
        client.write('Record2ndChoice:')
        # Audacity 2.4.2 requires waiting for recording to complete.
        if LEGACY:
            sleep(params['duration'] + 1)
        client.write('SelectAll:')
        client.write(f'Export2: Filename={filename} NumChannels={chans}')
        client.write('RemoveTracks:')


# Configuration options.
# Overrides interactive options when 'USE_CONFIG = True'.
USE_CONFIG = False

CONFIG: dict = {'ext': 'mp3',         # Export format
                'fname': 'myaudio',   # Root file name
                'fpath': Path('~/Desktop/mytest'),  # Export directory
                'duration': 10.0,  # Duration of each recording (seconds)
                'rcount': 3        # Number of recordings
                }

# Older versions of Audacity (including 2.4.2) requires waiting for
# recording to complete before exporting. We can't know the exact time
# it will take Audacity to initiate recording, so by default this script
# allows 'duration + 1' seconds for recording to complete. This
# workaround is not required for later versions of Audacity and may
# be disabled by setting 'LEGACY = False'.
LEGACY = True

if __name__ == '__main__':
    if USE_CONFIG:
        config: dict = CONFIG
    else:
        config = {}
        print('\nConfigure output location:')
        print('==========================')
        config['ext'] = config_ext()
        config['fname'] = config_fname(config['ext'])
        config['fpath'] = config_fpath(config['fname'], config['ext'])
        print('\nConfigure length and number of recordings:')
        print('==========================================')
        config['duration'], config['rcount'] = config_recordings()
    print(config)
    sys.exit(main(config))