prometheus-clj

⚠️ Archived: This prometheus-clj project isn't longer maintained by SoundCloud. Check out iapetos for an actively maintained Clojure wrapper around the official Prometheus Java Client.

Installation

Leiningen

prometheus-clj is available from Clojars.

Usage

Require prometheus core.

(:require [prometheus.core :as prometheus])

Wrap your ring handler so the prometheus client can start collecting metrics about your requests.

(prometheus/instrument-handler handler your-app-name your-prometheus-collector-registry)

Create a compojure route so that the prometheus server can poll your application for metrics.

(GET "/metrics" [] (prometheus/dump-metrics your-prometheus-collector-registry))

Example with custom metrics

(ns prometheus.example
  (:require [prometheus.core :as prometheus]
            [ring.server.standalone :refer [serve]]))

(defonce store (atom nil))

(defn register-metrics [store]
  (->
    store
    (prometheus/register-counter "test" "some_counter" "some test" ["foo"])
    (prometheus/register-gauge "test" "some_gauge" "some test" ["foo"])
    (prometheus/register-histogram "test" "some_histogram" "some test" ["foo"] [0.7 0.8 0.9])))

(defn init! []
  (->> (prometheus/init-defaults)
       (register-metrics)
       (reset! store)))

(defn handler [_]
  (prometheus/increase-counter @store "test" "some_counter" ["bar"] 3)
  (prometheus/set-gauge @store "test" "some_gauge" 101 ["bar"])
  (prometheus/track-observation @store "test" "some_histogram" 0.71 ["bar"])
  (prometheus/dump-metrics (:registry @store)))


(defn -main [&]
  (init!)
  (serve
    (prometheus/instrument-handler handler
                                   "test_app"
                                   (:registry @store))))

Run the example server:

lein run -m prometheus.example

License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0