Get volumes from pulseaudio using pactl

pa-volumes-1.py

#Requires python 3.6 or up (tested on 3.7.4
import subprocess, os, sys, re
from collections import defaultdict

volume_pattern = re.compile(r'^\s*volume:\s+(.*)', re.I)
sink_id_pattern = re.compile(r'^\s*sink\s+#(.*)', re.I)
description_pattern = re.compile(r'^\s*description:\s+(.*)', re.I)
volume_entry_pattern = re.compile(r'(^|\s+)(?P<name>.*?):\s+(?P<volume_raw>.*?)\s*/\s*(?P<volume_percent>.*?)\%\s*/\s*(?P<volume_db>.*?)\s+db', re.I)

def run_command(*cmd):
	mod_env = dict(**os.environ)
	mod_env['LANG'] = 'C'
	p = subprocess.Popen(cmd, stdout=subprocess.PIPE,env=mod_env)
	raw_stdout, dummy = p.communicate()

	stdout = raw_stdout.decode(sys.getdefaultencoding())

	return stdout

def parse_volume(line):
	return [match.groupdict() for match in volume_entry_pattern.finditer(line)]

def get_volumes():

	result = defaultdict(dict)
	current_sink_id = None	

	data = run_command('pactl', 'list', 'sinks')
	try:
		for line in data.split('\n'):
			v_match = volume_pattern.match(line)
			s_match = sink_id_pattern.match(line)
			d_match = description_pattern.match(line)

			if s_match:
				current_sink_id = int(s_match.group(1))

			if v_match:
				assert current_sink_id != None, 'Found volume before a current sink id!'
				result[current_sink_id]['volume'] = parse_volume(v_match.group(1))

			if d_match:
				assert current_sink_id != None, 'Found description before a current sink id!'
				result[current_sink_id]['description'] = d_match.group(1)

	except AssertionError:		
		print(data, file=sys.stderr)
		raise

	return result

current_volumes = get_volumes()
for sink, data in current_volumes.items():
	print(f'Sink #{sink} ({data["description"]})')
	for entry in data['volume']:
		print(f'\t{entry}')
	print()