Metrics
The Mercure.rocks Hub relies on Caddy's metrics and extends them with Mercure-specific collectors.
Enable Caddy's Prometheus scrape endpoint as described in the Caddy documentation. In addition to Caddy's HTTP, filesystem, and reverse-proxy metrics, the Hub registers the following collectors:
| Name | Type | Description |
|---|---|---|
mercure_subscribers_total | Counter | Total number of subscribers handled since the hub started |
mercure_subscribers_connected | Gauge | Current number of connected subscribers |
mercure_updates_total | Counter | Total number of updates dispatched since the hub started |