Configuring Prometheus

cron.roflcopter.fr supports exporting metrics and check statuses to Prometheus, for use with Grafana.

You can generate the metrics export endpoint by going to your project settings and creating a read-only API key. You will then see the link to the Prometheus endpoint:

Project's API Keys

Update the prometheus.yml

You can copy the Prometheus endpoint URL and add it to the Prometheus configuration:

  - job_name: "healthchecks"
    scrape_interval: 60s
    scheme: https
    metrics_path: /projects/{your-project-uuid}/metrics/{your-readonly-api-key}
    static_configs:
      - targets: ["cron.roflcopter.fr"]

Notice how we split up the URL and paste in the scheme, domain, and path separately.

Reload Prometheus, and your changes should be live, coming in under the hc_ prefix.

Available Metrics

The Prometheus metrics endpoint exports the following metrics:

hc_check_up

For every check, indicates whether the check is currently up (1 for yes, 0 for no).

Labels:

  • name – the name of the check
  • tags – check's tags as a text string; multiple tags are delimited with spaces
  • unique_key – a stable, unique identifier of the check (derived from the check's code)
hc_check_started

For every check, indicates whether the check is currently running (1 for yes, 0 for no).

Labels:

  • name – the name of the check
  • tags – check's tags as a text string; multiple tags are delimited with spaces
  • unique_key – a stable, unique identifier of the check (derived from the check's code)
hc_tag_up

For every tag, indicates whether all checks with this tag are up (1 for yes, 0 for no).

Labels:

  • tag – name of the tag
hc_checks_total
The total number of checks.
hc_checks_down_total

The number of checks currently down.

Constructing URLs to Check Details Pages

You can use the unique_key labels to construct URLs to check's details pages in cron.roflcopter.fr. Construct the URLs like so:

https://cron.roflcopter.fr/cloaked/{unique_key}/