Check if a list of URLs has had any content changed. Useful for websites with no RSS feed

check.py

import os
from requests import get
from hashlib import md5


urls = ['http://ststephens.edu/',
        'http://cmi.ac.in/']

try:
    with open('.website_signatures', 'r') as fl:
        old_signature = fl.readlines()
except IOError:
    old_signature = ['' for _ in urls]

# wait for internet connection
wait = 1
while True:
    try:
        html = [get(u).text.encode('utf-8') for u in urls]
    except:
        import time
        time.sleep(wait)
        wait = wait * 2
    else:
        break


new_signature = [md5(h).hexdigest() for h in html]

changes = [old_sig == new_sig for old_sig, new_sig in zip(old_signature, new_signature)]

msg = ''
for changed, link in zip(changes, urls):
    if changed:
        msg += 'Changed     : '
    else:
        msg += 'Not Changed : '
    msg += link + '\n'
os.system('notify-send "Websites with changed contents" "{}"'.format(msg))

with open('.website_signatures', 'w') as fl:
    fl.writelines(map(lambda x: str(x) + '\n', new_signature))