nanoservice "api" which listens to "dyndns" requests from a router to update records on route53 (via shellscript) to be used in conjunction with https://gist.github.com/gretel/8bb0c2936ae5cda12ae5f0bf381dd3f0

nonstatic.py

#!/usr/bin/env python3
#

from flask import Flask, request
#from waitress import serve
from pid.decorator import pidfile
import ipaddress
import setproctitle
import subprocess

PIDDIR='.'
PORT=5001
SCRIPT='./upd_dyndns.sh'
TIMEOUT=60

app = Flask(__name__)
@app.route('/nonstatic', methods=['GET', 'POST'])
def nonstatic():
    try:
        arg_v4 = request.args.get('ipaddr', '')
        arg_v6 = request.args.get('ip6addr', '')
    except flask.KeyError:
        return 'nokey'

    try:
        ip_v4 = ipaddress.ip_address(arg_v4)
        ip_v6 = ipaddress.ip_address(arg_v6)
    except ValueError:
        return 'invalid'

    try:
        assert ip_v4.is_global
    except AssertionError:
        return 'invalid'
    finally:
        app.logger.debug('ip_v4: %s' % ip_v4)
        app.logger.debug('ip_v6: %s' % ip_v6)

    cmdline = "%s %s %s" % ( SCRIPT, str(ip_v4), str(ip_v6) )
    app.logger.debug('cmdline: %s' % cmdline)

    try:
        result = subprocess.run([cmdline], shell=True, check=True, close_fds=True, timeout=TIMEOUT, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    except subprocess.CalledProcessError as cpe:
        print(cpe)
        if cpe.returncode > 1:
            return 'error'
    except subprocess.TimeoutExpired as te:
        print('subprocess timeout (%s' % te.timeout)
        return 'timeout'
    finally:
        print(result.stdout.decode("utf-8", errors="ignore"))
        if result.returncode == 1:
            return 'changed'
        return 'nochange'

@pidfile('nonstatic.pid', piddir=PIDDIR)
def main():
    setproctitle.setproctitle('nonstatic')
    app.run(host='127.0.0.1', port=PORT, debug=False) # flask
    #serve(app, host='127.0.0.1', port=PORT) # waitress

if __name__ == '__main__':
    main()

upd_dyndns.sh

#!/bin/sh
#
echo "$@"

# virtualenv
. bin/activate

# update records
./course53.py --domain yhamster.us --subdomain vidsrv --zone DKS03KALD120SK --ipaddress "${2}" --record_type AAAA
./course53.py --domain yhamster.us --subdomain vidsrv --zone DKS03KALD120SK --ipaddress "${1}"