nsolid-graphite/daemon.js

a daemon that sends N|Solid metrics to graphite

#!/usr/bin/env node

'use strict'

const pkg = require('./package.json')
const util = require('./lib/util')
const config = require('./lib/config')
const graphite = require('./lib/graphite')
const nsolid = require('./lib/nsolid')

const conf = getConfig()
util.debug('config: %j', conf)

const graphiteClient = graphite.createClient(conf)
const nsolidClient = nsolid.createClient(conf)

process.title = 'nsolid-graphite'

console.log(`Sending metrics to:   graphite server: ${conf.graphiteAddress}`)
console.log(`Sending metrics from: N|Solid storage: ${conf.nsolidAddress}`)

// This creates a stream and only has to be done once
nsolidClient.getMetrics(gotNSolidMetrics)

function gotNSolidMetrics (err, stats) {
  if (err) return console.error(`Error getting N|Solid process stats: ${err.message}`)
  if (!stats) return

  graphiteClient.sendNSolidMetrics(stats)
}

function getConfig () {
  let conf

  try {
    conf = config.getConfig('nsolid-graphite')
  } catch (e) {
    exit(1, () => console.error(e.message))
  }

  if (conf.help) exit(0, () => util.printHelp())
  if (conf.version) exit(0, () => console.log(pkg.version))

  return conf
}

// run a function, then exit with specified status code
function exit (statusCode, fn) {
  fn()
  process.exit(statusCode)
}

process.on('SIGTERM', () => {
  exit(0, () => console.log('Shutting down'))
})