Python script to notify via email when connection resumes

check-connection.py

"""
This script determines if your internet connection is up by attempting to open a connection to a specified host.
You can also provide the 'notify' command and an email address to continually monitor for a resumed connection.
I use this specifically to send myself a text in the case where my home connection is out and I went to a coffee 
shop, library, etc. in the meantime.  

Disclaimer: I'm a python n00b so I'm sure there are better/simpler ways to do this.  
License: MIT
"""

import socket
import smtplib
import sys
import urllib2
import string
from time import sleep

REMOTE_IP   = '8.8.8.8'             # Cannot be hostname, 8.8.8.8 is Google's DNS Server
REMOTE_PORT = 53                    # Use 80 if trying a website, 53 is DNS port
GMAIL_USER  = 'YOUR_GMAIL_SEND_ADDRESS'
GMAIL_PASS  = 'YOUR_GMAIL_SEND_PASSWORD'
RETRY_TIME  = 60                    # Time between connection attempts (when notification command is sent)


def get_ip():
    # lazy way to get ip address.  obviously won't work if this service is unreachable
    response = urllib2.urlopen("http://api.ipify.org")
    return response.read()


def are_we_connected():
    try:
        s = socket.create_connection((REMOTE_IP, REMOTE_PORT), 2)
        s.close()
        return True
    except:
        pass

    return False


def notify_when_fixed(email_addr):
    while (are_we_connected() != True):
        print 'No connection, trying again in %d seconds' % (RETRY_TIME)
        sleep(RETRY_TIME)

    ip_addr = get_ip()
    msg = "Connection is back up!  IP address is: %s" % (ip_addr)
    print msg
    send_notification_email(email_addr, msg)


def send_notification_email(email_addr, message):
    body = string.join((
            "From: %s" % GMAIL_USER,
            "To: %s" % email_addr,
            "Subject: Connection Successful",
            "",
            message
        ), "\r\n")

    try:
        s = smtplib.SMTP('smtp.gmail.com', 587)
        s.ehlo()
        s.starttls()
        s.ehlo()
        s.login(GMAIL_USER, GMAIL_PASS)
        s.sendmail(GMAIL_USER, [email_addr], body)
    except Exception,e:
        print "ERROR: ",e
    finally:
        s.quit()


def usage():
    print "Usage: "
    print "  %s - Print True or False if connection is up" % sys.argv[0]
    print "  %s notify [email] - Try to connect every %d seconds, send email and quit on sucess" % (sys.argv[0], RETRY_TIME)

# MAIN PROGRAM
if (len(sys.argv) == 1):
    print are_we_connected()
else:
    command = sys.argv[1]
    if (command == 'notify'):
        if (len(sys.argv) > 2):
            notify_when_fixed(sys.argv[2])
        else:
            print "Error: You must provide the notification email"
    elif (command == 'h' or command == 'help'):
        usage()
    else:
        print " - I don't understand that command - \n"
        usage()