Usage with Grafana Alloy

[bazalt]

Hello,
I'm trying to collect PHP-FPM metrics with Grafana Alloy.

Many Alloy components exist, that embed apache exporter, mysql exporter, and so on.

Is there a plan to package php-fpm-exporter as an Alloy component?
Otherwise, how would you configure Alloy to collect metrics from php-fpm-exporter please?

Thank you!

[Skyrail]

Hey @bazalt - this may seem a little unorthodox (given this GitHub project) but I setup Alloy earlier today to export php-fpm metrics without using any extra exporters. Since PHP8.1 the php-fpm status page has supported OpenMetrics which you can scrape using something like:

prometheus.scrape "php_fpm_metrics" {
	targets = [
		{
			"__address__" = "localhost:80",
			"instance"    = constants.hostname,
		},
	]

	forward_to = [prometheus.remote_write.metrics_service.receiver]

	scrape_interval = "60s"
	params          = {
		"openmetrics" = [""],
	}
	metrics_path = "/fpm-status"
}

The key is adding 'openmetrics' as a query parameter, the above will resolve to localhost:80/fpm-status?openmetrics="" which works fine for me - you'll have to tweak the details to whatever suits your needs.

(Note: the php-fpm status page doesn't support openmetrics & full metrics (see php/php-src#9494))

[bazalt]

Thank you @Skyrail for this clean and documented answer, very appreciated 👍️! I learned a lot.

Since I also need to support PHP < 8.1, I dug down to the following Alloy configuration, that use hipages/php-fpm-exporter, and that seems working so far:

prometheus.scrape "php" {
  targets = [{
     __address__ = "php-fpm-exporter:9253",   # The `php-fpm-exporter` container address. Must be accessible from Alloy container.
    __metrics_path__ = "/metrics",
  }]
  forward_to        = [your.receiver.here]
  scrape_interval   = "15s"
}

Hope this can help someone.
Anyway, thanks again !