Battery monitor script for Linux computers.

batmon.py

#!/usr/bin/env python3

"""
Copyright © 2021 Siddharth Singh

The MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

    * The above copyright notice and this permission notice
    shall be included in all copies or substantial portions
    of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""

import re
import subprocess
import gi
import time
import os

gi.require_version("Notify", "0.7")

from gi.repository import Notify
from gi.repository import GdkPixbuf

Notify.init("BatteryMonitor")

def get_stdout(cmd):
    args = cmd.split()
    output = subprocess.run(args, capture_output=True)
    return output.returncode, output.stdout.decode('UTF-8')

def check():
    _, output = get_stdout('acpi --battery')
    percs = list(map(lambda x: int(x.replace('%', '')),
                     re.findall(r'\d+%', output)))

    percs.sort(reverse=True)

    if 'Discharging' in output:
        if percs[0] < 7:
            notification(f'Battery at {percs[0]}%.', 'Suspending', Notify.Urgency.CRITICAL, Notify.EXPIRES_NEVER)
            time.sleep(1)
            os.system('systemctl suspend')

        elif percs[0] < 10:
            notification(f'Battery at {percs[0]}%.', 'Battery below 10%. Plug in now.', Notify.Urgency.CRITICAL, Notify.EXPIRES_NEVER)
        
        elif percs[0] < 20:
            notification('Battery getting low.', f'Battery at {percs[0]}. Plug in now.', Notify.Urgency.NORMAL, Notify.EXPIRES_DEFAULT)

def notification(title, message, urgency, expiry):
    notif = Notify.Notification.new(title, message, None)
    notif.set_urgency(urgency)
    notif.set_timeout(expiry)

    notif.show()

if __name__ == "__main__":
    notification('Battery monitor started.', '', Notify.Urgency.LOW, Notify.EXPIRES_DEFAULT)

    while True:
        try:
            check()
            time.sleep(30)
        except:
            exit(0)