monitoring-scripts/cert-checker.py

#!/usr/bin/env python3
import datetime
import socket
import ssl
import requests


def get_cert(domain):
    context = ssl.create_default_context()
    conn = context.wrap_socket(
        socket.socket(socket.AF_INET),
        server_hostname=domain,
    )
    # 3 second timeout because Lambda has runtime limitations
    conn.settimeout(3.0)

    conn.connect((domain, 443))
    return conn.getpeercert()


def ssl_alt_names(ssl_info):
    return [item[1] for item in ssl_info['subjectAltName']]


def ssl_valid_time_remaining(ssl_info):
    ssl_date_fmt = r'%b %d %H:%M:%S %Y %Z'
    expires = datetime.datetime.strptime(ssl_info['notAfter'], ssl_date_fmt)
    return expires - datetime.datetime.utcnow()


def check_domain(domain):
    cert = get_cert(domain)
    t_remaining = ssl_valid_time_remaining(cert)
    return t_remaining.days + t_remaining.seconds / 86400


def post_data(domain, time):
    db = 'scripts_data'
    INFLUXDB_HOST = "http://grafana.labs:8086/write?db=%s" % db
    data = 'days_remaining,hostname=%s value=%.2f' % (domain, time)
    headers = {'Content-Type': 'application/octet-stream'}
    r = requests.post(INFLUXDB_HOST, data=data, headers=headers)
    if r.status_code < 200 or r.status_code > 300:
        print("When posting %s I got status_code %d" % (domain, r.status_code))


hosts = [ 'labs.davidventura.com.ar', 'especificosba.com.ar', 'casa.especificosba.com.ar' ]
data = []
for h in hosts:
	try:
		t = check_domain(h)
		data.append((h,t))
	except Exception as e:
		print("Exception while contacting %s" % h)
		print(e)

for d in data:
	post_data(*d)