Configuring Prometheus

Cron Monitor Celsius Online 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: ["healthchecks.celsius-online.com"]

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 Monitor Celsius Online. Construct the URLs like so:

https://healthchecks.celsius-online.com/cloaked/{unique_key}/