Using Puppeteer to emulate Network Information API

networkinformation.js

const puppeteer = require('puppeteeer');

const networkConditions = {
  '2g': {
    downloadThroughput: 500 * 1024 / 8 * .8,
    uploadThroughput: 500 * 1024 / 8 * .8,
    latency: 400 * 5,
    offline: false,
  },
  '3g': {
    downloadThroughput: 1.6 * 1024 * 1024 / 8 * .9,
    uploadThroughput: 750 * 1024 / 8 * .9,
    latency: 150 * 3.75,
    offline: false,
  },
  'offline': {
    downloadThroughput: 0,
    uploadThroughput: 0,
    latency: 0,
    offline: true,
  },
  'no throttling': {
    downloadThroughput: -1,
    uploadThroughput: -1,
    latency: 0,
    offline: false,
  },
};

(async () => {
  const browser = await puppeteer.launch();
  const page = await browser.newPage();
  // Use raw protocol to configure network conditions.
  const session = await page.target().createCDPSession();
  await session.send('Network.emulateNetworkConditions', networkConditions['3g']);
  await session.detach();
  // Keep using Puppeteer API to drive automation.
  await page.goto('https://example.com');
  // Fetch connection effective type.
  console.log(await page.evaluate(() => navigator.connection.effectiveType));
  await browser.close();
})();

i think its not working!