Monitor the connection state to an Access Point on a Mac OS computer

mac_connected_ap.py

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

"""
Tool to output the state of connection to an AP on a Mac OS computer.

Usage:
    mac_connected_ap.py [options] [-q | -v] INTERFACE...

Arguments:
    INTERFACE                 Interface to use [default: "en1"]

Other options:
    -h, --help                show this help message and exit
    -q, --quiet               print less text
    -v, --verbose             print more text
    --version                 show version and exit
"""

__author__ = "Jasper Buesch"
__copyright__ = "Copyright (c) 2014, Technische Universität Berlin"
__version__ = "0.1.0"
__email__ = "buesch@tkn.tu-berlin.de"

# coding: utf-8

import subprocess
import time
import logging


call = "/System/Library/PrivateFrameworks/Apple80211.framework/Versions/A/Resources/airport -I en1"


def get_if_state(cmd_call):
	return subprocess.check_output(cmd_call, shell=True)


def main(args):
	cmd_call = call % (args["INTERFACE"])
	log = logging.getLogger("main")
	while True:
		output = get_if_state(cmd_call)
		if output.strip().startswith("AirPort: Off"):
			log.fatal("Airport reports that WIFI is switched off!")
			while output.strip().startswith("AirPort: Off"):
				output = get_if_state(cmd_call)
				time.sleep(0.5)
			continue
		output_lines = output.split("\n")
		bssid = None
		agrCtlRSSI = None
		for line in output_lines:
			striped_line = line.strip()
			if striped_line.startswith("agrCtlRSSI: "):
				agrCtlRSSI = striped_line.split("agrCtlRSSI: ")[1]
			if striped_line.startswith("BSSID: "):
				bssid = striped_line.split("BSSID: ")[1]
				break
		if bssid == "0:0:0:0:0:0":
			log.info("Not connected")
		else:
			log.info("Connected to AP %s with RSSI %s" % (bssid, agrCtlRSSI))
		time.sleep(1)


if __name__ == "__main__":
    try:
        from docopt import docopt
    except:
        print("""
        Please install docopt using:
            pip install docopt==0.6.1
        For more refer to:
        https://github.com/docopt/docopt
        """)
        raise

    args = docopt(__doc__, version=__version__)

    log_level = logging.INFO  # default
    if args['--verbose']:
        log_level = logging.DEBUG
    elif args['--quiet']:
        log_level = logging.ERROR
    logging.basicConfig(level=log_level,
        format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')
    main(args)