aws_ip_range_change_notification.py

import requests # Needs to be installed
import json
import smtplib
from email.mime.text import MIMEText
import os

FILENAME = 'aws_ips.json' # local storage for comparison 
SMTP_SERVER = 'smtp.potato.local'
SEND_FROM = 'from@example.com'
SEND_TO = 'to@example.com'

SITE_ROOT = os.path.dirname(os.path.realpath(__file__))
def main():
	'''Compare changes to the IP address ranges that Amazon uses for us-east-1 and 2'''

	def compare_ips():

		new_addresses = []
		for i in new['ip_addresses']:
			if i not in old['ip_addresses']:
				new_addresses.append(i)
		
		if len(new_addresses) == 0:
			print "Something was removed"
			exit()
		return new_addresses

	def send_notice(new_addresses):

		try:
			message_text = """The AWS IP Address Block has changed!
			Please add these to the Securly Firewall Rules.\n 
			Date Created:\t%s 
			Last Modified:\t%s\n 
			New IP Addresses:\n%s"""
			msg = MIMEText(message_text.replace('\t\t\t','')
			% (new['createDate'],old['createDate'],'\n'.join(new_addresses))
			)
			msg['Subject'] = '[Warning] AWS IP Range Change!'
			msg['From'] = SEND_FROM
			msg['To'] = SEND_TO
		except:
			print "something went wrong with mail!"
			exit()
		s = smtplib.SMTP(SMTP_SERVER)
		s.sendmail(SEND_FROM,SEND_TO, msg.as_string())
		s.quit
	
	# Read previous values	
	try:
		with open('%s/%s' % (SITE_ROOT,FILENAME), 'r') as f:
			old = json.loads(f.read())
	except:
		print "File not found or file not json."
	
	# Get new json file from AWS 
	r = requests.get('https://ip-ranges.amazonaws.com/ip-ranges.json')
	# Test that we can connect to the json file
	try:
		r.raise_for_status()
	except requests.exceptions.HTTPError as e:
		print(e.message)
		sys.exit(1)
	ranges = r.json()
 
	# This dictionary will hold the IP ranges from us-east-1 and us-east-2
	new = {}
	new['ip_addresses'] = []

	# for testing
# 	new['ip_addresses'].append('13.1.1.01/24')
# 	new['ip_addresses'].append('10.12.1.92/28')
# 	new['ip_addresses'].append('13.1.11.12/14')

	# Add the createDate - for the email
	new['createDate'] = ranges['createDate']
 
	# Add IPs to list within dictionary 
	for i in ranges['prefixes']:
		if i['region'] == 'us-east-1' or i['region'] == 'us-east-1':
			new['ip_addresses'].append(i['ip_prefix'])
	
	try:
		# Test to see if we read the old file in 
		if new == old:
			print "No Range Changes Detected!"
		else:
			send_notice(compare_ips())
	except:
		print "Nothing to compare - First Run or something was removed"	
		
	# Write current values		
	with open('%s/%s' % (SITE_ROOT,FILENAME), 'w') as f:
		json.dump(new, f)
		
if __name__ == '__main__':
	main()