Module: Lepus::Prometheus

Defined in:
lib/lepus/prometheus.rb,
lib/lepus/prometheus/collector.rb,
lib/lepus/prometheus/instrumentation.rb

Overview

Optional integration with the prometheus_exporter gem. Require “lepus/prometheus” in your Lepus process to start shipping metrics to a running prometheus_exporter server via the default client.

On the prometheus_exporter server side, load the companion collector:

prometheus_exporter -a lepus/prometheus/collector

Defined Under Namespace

Modules: Instrumentation Classes: Collector

Constant Summary collapse

DEFAULT_QUEUE_POLL_INTERVAL = 
30

Class Attribute Summary collapse

Class Method Summary collapse

Class Attribute Details

.client ⇒ Object 



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# File 'lib/lepus/prometheus.rb', line 21

def client
  @client ||= ::PrometheusExporter::Client.default
end

Class Method Details

.emit(metric, **data) ⇒ Object

Emit an opaque metric payload to the exporter server. Silently swallows transport errors so instrumentation cannot break the caller; non-transport bugs surface as debug logs.



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# File 'lib/lepus/prometheus.rb', line 28

def emit(metric, **data)
  client.send_json(type: "lepus", metric: metric.to_s, **data)
rescue => e
  Lepus.logger.debug { "[Lepus::Prometheus] emit(#{metric}) failed: #{e.class}: #{e.message}" }
  nil
end

.stop_watching_queues ⇒ Object 



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# File 'lib/lepus/prometheus.rb', line 43

def stop_watching_queues
  Instrumentation::QueuePoller.stop
end

.watch_queues(interval: DEFAULT_QUEUE_POLL_INTERVAL, api: nil) ⇒ Object

Start polling the RabbitMQ management API for queue-level gauges. Safe to call once per process. Requires “lepus/web/management_api”.



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# File 'lib/lepus/prometheus.rb', line 37

def watch_queues(interval: DEFAULT_QUEUE_POLL_INTERVAL, api: nil)
  require "lepus/web/management_api"
  api ||= Lepus::Web::ManagementAPI.new
  Instrumentation::QueuePoller.start(interval: interval, api: api)
end