README.md

Check IP

Have your Raspberry Pi report its WIFI IP on boot via email. This works well with the Edimax EW-7811n WIFI Adapter.

Installation

Download the check_ip.py file:

wget https://gist.github.com/raw/4441249/check_ip.py

Edit the variables at the top of the script to add your own email credentials. Setting up a standalone gmail account to do the actual email sending would be a good idea.

Setup the script to run on boot with the following:

chmod 755 check_ip.py
sudo cp check_ip.py /etc/init.d/
sudo update-rc.d check_ip.py defaults 19

For help setting up the Edimax wifi adapter, check out this document. I just edited the /etc/network/interfaces and /etc/wpa_supplicant.conf files.

check_ip.py

#!/usr/bin/python
# The idea behind this script is if plugging a RaspberryPi into a foreign network whilst running it headless
# (i.e. without a monitor/TV), you need to know what the IP address is to SSH into it.
#
# This script emails you the IP address if it detects an ethernet address other than it's usual address
# that it normally has, i.e. on your home network.  

import smtplib, string, subprocess, time, os

################################################
###### Remember to set all constants here ######
################################################
FIXED_IP = '10.0.1.2'
IP_FILEPATH = '~/current_ip.txt'
SMTP_USERNAME = '[email protected]'
SMTP_PASSWORD = 'password'
SMTP_RECIPIENT = '[email protected]'
SMTP_SERVER = 'smtp.gmail.com'
SSL_PORT = 465
################################################

IP_FILEPATH = os.path.expanduser(IP_FILEPATH)

adapter = 'wlan0:'
ipaddr_string = 'ip -4 addr > ' + IP_FILEPATH
subprocess.call(ipaddr_string, shell=True)
inet_string = ''

ip_file = file(IP_FILEPATH, 'r')
for line in ip_file:
        
    if adapter in line:
        inet_line = ip_file.next()
        _time = time.asctime()
        _mac = file('/sys/class/net/eth0/address').read()
        inet_string = inet_line[9:(inet_line.index('/'))]

        if inet_string:

            p = subprocess.Popen(["runlevel"], stdout=subprocess.PIPE)
            out, err=p.communicate()
            print out
            print out[2]
            if out[2] == '0':
                print 'Halt detected'
                exit(0)
            if out [2] == '6':
                print 'Shutdown detected'
                exit(0)

            SUBJECT = 'IP Address from Raspberry Pi at: %s' % time.asctime()
            TO = SMTP_RECIPIENT
            FROM = SMTP_USERNAME
            text = 'The IP address is: %s and the mac address is %s' % (inet_string, _mac)
            BODY = string.join((
                'From: %s' % FROM,
                'To: %s' % TO,
                'Subject: %s' % SUBJECT,
                '',
                text
                ), '\r\n')
            server = smtplib.SMTP_SSL(SMTP_SERVER, SSL_PORT)
            server.login(SMTP_USERNAME, SMTP_PASSWORD)
            server.sendmail(FROM, [TO], BODY)
            server.quit()

            print '[' + '\033[36;1m' + 'info'  + '\033[0m' + ']' + ' Emailing wlan0 IP address ' + inet_string + ' to ' + TO + ' from ' + FROM

ip_file.close()

rm_ipaddr_string = 'rm ' + IP_FILEPATH
subprocess.call(rm_ipaddr_string, shell=True)