You can actively signal a failure to Healthchecks by slightly changing the
ping URL: append either /fail
or /{exit-status}
to your normal ping URL.
The exit status should be a 0-255 integer. Healthchecks will interpret
exit status 0 as success and all non-zero values as failures.
Examples:
# Reports failure by appending the /fail suffix:
curl --retry 3 https://healthchecks.niyawe.de/ping/your-uuid-here/fail
# Reports failure by appending a non-zero exit status:
curl --retry 3 https://healthchecks.niyawe.de/ping/your-uuid-here/1
By actively signaling failures to Healthchecks, you can minimize the delay from your monitored service encountering a problem to you getting notified about it.
The below shell script appends $?
(a special variable that contains the
exit status of the last executed command) to the ping URL:
#!/bin/sh
/usr/bin/certbot renew
curl --retry 3 https://healthchecks.niyawe.de/ping/your-uuid-here/$?
Below is a skeleton code example in Python which signals a failure when the work function returns an unexpected value or throws an exception:
import requests
URL = "https://healthchecks.niyawe.de/ping/your-uuid-here"
def do_work():
# Do your number crunching, backup dumping, newsletter sending work here.
# Return a truthy value on success.
# Return a falsy value or throw an exception on failure.
return True
success = False
try:
success = do_work()
finally:
# On success, requests https://healthchecks.niyawe.de/ping/your-uuid-here
# On failure, requests https://healthchecks.niyawe.de/ping/your-uuid-here/fail
requests.get(URL if success else URL + "/fail")