Expose Brakes metrics as Prometheus data

Usage no npm install needed!

<script type="module">
  import finnNoNodeBrakesPrometheus from 'https://cdn.skypack.dev/@finn-no/node-brakes-prometheus';



Expose Brakes metrics as Prometheus data

[![NPM Version][npm-image]][npm-url] [![Build Status][travis-image]][travis-url]


Add event listeners to a [brakes][brakes-url] instance, using prom-client. This module has a peer dependency on [prom-client][prom-client-url].

import Brake from 'brakes';
import addEventListeners from '@finn-no/brakes-prometheus';
import { register as prometheusRegister } from 'prom-client';

const myBrake = new Brake(() => Promise.resolve(), { name: 'some name' });


setInterval(() => {
}, 500);

Naming metrics

You can supply an additional options object to set a prefix for the metric names.

addEventListeners(myBrake, { prefix: 'my_application_prefix_' });

// provides "my_application_prefix_breaker_execute_total" and so on

Metrics exposed

This module exposes 9 metrics, all using the name of the Brake as the label:

  1. breaker_execute_total, 'Resolver circuit breaker execute count' (Counter)
  2. breaker_success_total, 'Resolver circuit breaker success count' (Counter)
  3. breaker_failure_total, 'Resolver circuit breaker failure count' (Counter)
  4. breaker_timeout_total, 'Resolver circuit breaker timeout count' (Counter)
  5. breaker_reject_total, 'Resolver circuit breaker reject count' (Counter)
  6. breaker_circuit_closed_total, 'Resolver circuit breaker circuit closed count' (Counter)
  7. breaker_circuit_opened_total, 'Resolver circuit breaker circuit opened count' (Counter)
  8. breaker_duration_seconds: 'Resolver circuit breaker duration summary' (Summary)
  9. breaker_duration_buckets_seconds: 'Resolver circuit breaker duration buckets' (Histogram)