Print navigation timing in your browser

printTiming.js

const events = [ 'domLoading', 'domInteractive', 'domContentLoadedEventEnd', 'domComplete', 'loadEventEnd' ];
const startEvent = 'navigationStart';

const timing = performance.timing;

const compose = (f, g) => x => f(g(x));

const timeFromNavigationStart = event => differenceInSeconds(timing[event], timing[startEvent]);
const differenceInSeconds = (t1, t2) => (t1 - t2) / 1000;
const sanitizeTime = t => (t > 0) ? t : 'N/A - Has not fired yet - please run console log again';

const getTimeDifference = compose(sanitizeTime, timeFromNavigationStart);

const buildEventsArray = events => events.map((event) => {
  const timeDifference = getTimeDifference(event);
  return new Event(event, timeDifference);
});

class Event {
  constructor(navigationTiming, seconds) {
    this.navigationTiming = navigationTiming;
    this.seconds = seconds;
  }
}

console.table(buildEventsArray(events));