@ministryofjustice/fb-jwt-client-node/got-test.js

const got = require('got')
// const convertHrtime = require('convert-hrtime')
const prometheus = require('prom-client')

const options = {
  url: 'http://localhost:44444/counter',
  json: true,
  retry: {
    retries: 3,
    xerrorCodes: ['ERR_SOCKET_BAD_PORT']
  }
}

let allTimings = []
let starter
let finisher

const apiMetrics = new prometheus.Histogram({
  name: 'api_requests',
  help: 'API calls using FB JWT Client',
  labelNames: ['client_name', 'baseUrl', 'url', 'method', 'status_code', 'status_message', 'error_name'],
  buckets: [0.1, 0.25, 0.5, 1, 2, 5, 10]
})

const requestMetrics = new prometheus.Histogram({
  name: 'jwt_client_requests',
  help: 'HTTP requests using FB JWT Client',
  labelNames: ['client_name', 'baseUrl', 'url', 'method', 'status_code', 'status_message', 'error_name'],
  buckets: [0.1, 0.25, 0.5, 1, 2, 5, 10]
})

const getResponseLabels = (response) => {
  const responseLabels = {
    status_code: response.statusCode
  }
  if (response.statusMessage) {
    responseLabels.status_message = response.statusMessage
  }
  if (response.name) {
    responseLabels.error_name = response.name
  }
  return responseLabels
}
let requestMetricsEnd

const client = got.extend({
  timeout: 1000,
  hooks: {
    afterResponse: [
      (response, retryWithMergedOptions) => {
        requestMetricsEnd(getResponseLabels(response))
        // finisher = process.hrtime(starter)
        // allTimings.push(finisher) response.body
        console.log('afterResponse', response.statusCode) //, Object.keys(response)) //, response) //, response.timings)
        return response
      }
    ],
    beforeRequest: [
      (options, error, retryCount) => {
        requestMetricsEnd = requestMetrics.startTimer()
        // starter = process.hrtime()
        console.log('beforeRequest')
      }
    ],
    beforeRetry: [
      (options, error, retryCount) => {
        requestMetricsEnd = requestMetrics.startTimer()
        // starter = process.hrtime()
        console.log('beforeRetry', {retryCount}) //, error)
      }
    ],
    beforeError: [
      error => {
        requestMetricsEnd(getResponseLabels(error))
        // finisher = process.hrtime(starter)
        // allTimings.push(finisher)
        console.log('beforeError') //, error)
        return error
      }
    ]
  }
})

const fire = async () => {
  const apiMetricsEnd = apiMetrics.startTimer()
  // const totalRepsonseStart = process.hrtime()
  try {
    const response = await client.get(options)
    apiMetricsEnd(getResponseLabels(response))
    const {body, retryCount} = response
    console.log({body, retryCount})
  } catch (e) {
    apiMetricsEnd(getResponseLabels(e))
    console.log('e', e ? e.body : 'no body')
  }

  // const totalRepsonseElapsed = process.hrtime(totalRepsonseStart)
  // allTimings.forEach(timing => {
  //   console.log(convertHrtime(timing))
  // })
  // console.log('totes', convertHrtime(totalRepsonseElapsed))
  console.log(prometheus.register.metrics())
}

fire()