Cisco EPC3825 retriever for ddclient

epc3825ip.py

#!/usr/bin/env python3

import argparse
import requests
import sys
from lxml import html

parser = argparse.ArgumentParser(description='Retrieves IP from EPC3825 routers.')
parser.add_argument('--base', help='Base router prefix', default='http://192.168.0.1')
parser.add_argument('username', help='Administration user name')
parser.add_argument('password', help='Administration password')
args = parser.parse_args()

base = args.base.rstrip('/')
sess = requests.Session()

data = {
	'username_login': args.username,
	'password_login': args.password,
	'LanguageSelect': 'en',
	'Language_Submit': '0',
	'login': 'Log in'
}
reply = sess.post(base + '/goform/Docsis_system', data, allow_redirects=False)

if reply.status_code != 200:
	if reply.status_code != 302:
		print('Expected 200 or 302, got %d' % reply.status.code, file=sys.stderr)
		sys.exit(1)

	redirloc = reply.headers['location']
	if not redirloc.endswith('/Quick_setup.asp'):
		if redirloc.endswith('/Docsis_system.asp'):
			print('Invalid user or password', file=sys.stderr)
		else:
			print('Unexpected redirection to %s' % redirloc, file=sys.stderr)
		sys.exit(1)

reply = sess.get(base + '/Status.asp')
dom = html.fromstring(reply.text)

ipTd = dom.get_element_by_id('InternetIPAddress')
if ipTd is None:
	print('Cannot find IP field', file=sys.stderr)
	sys.exit(1)

print(ipTd.find('../td[2]').text_content())