+#! /usr/bin/python3
+
+import os
+import requests
+import time
+import calendar
+import logging
+from email.utils import parsedate
+logging.basicConfig(level=logging.INFO)
+
+HOSTS = os.environ['MIRROR_CHECK_HOSTS'].split()
+OUTPUT_DIR = "/run/dsa-mirror-health-{}".format(os.environ['MIRROR_CHECK_SERVICE'])
+HEALTH_FILE = os.path.join(OUTPUT_DIR, "health")
+URL = os.environ['MIRROR_CHECK_URL']
+INTERVAL = int(os.environ.get('MIRROR_CHECK_INTERVAL', '60'))
+
+latest_tz = 0
+
+def retrieve_from_host(host, url):
+ proxies = {
+ 'http': 'http://{}:80'.format(host),
+ 'https': 'http://{}:443'.format(host),
+ }
+ return requests.get(url, timeout=5, proxies=proxies)
+
+def last_modified(response):
+ lm = 0
+ if response.status_code == '200' and response.headers.get('last-modified'):
+ lm = calendar.timegm(parsedate(response.headers['last-modified']))
+ return lm
+
+while True:
+ start = time.time()
+ for host in HOSTS:
+ lm = last_modified(retrieve_from_host(host, URL))
+ logging.debug("lm for host %s: %s", host, lm)
+ if lm > latest_tz:
+ latest_tz = lm
+ local_lm = last_modified(retrieve_from_host('localhost', URL))
+ logging.debug("lm for localhost: %s", lm)
+ if latest_tz <= local_lm:
+ try:
+ logging.debug("considering myself unhealthy")
+ os.remove(HEALTH_FILE)
+ except OSError:
+ pass
+ else:
+ logging.debug("considering myself healthy")
+ open(HEALTH_FILE, 'w').write("OK")
+ sleep_time = start + INTERVAL - time.time()
+ logging.debug("sleeping for %d seconds", sleep_time)
+ time.sleep(sleep_time)