Simulating Network Throttling - Desktop Web and Mobile Web

const puppeteer = require('puppeteer');
let networkPresets = {
  'Good2G': {
    'offline': false,
    'downloadThroughput': 450 * 1024 / 8,
    'uploadThroughput': 150 * 1024 / 8,
    'latency': 150
  },
  'Regular3G': {
    'offline': false,
    'downloadThroughput': 750 * 1024 / 8,
    'uploadThroughput': 250 * 1024 / 8,
    'latency': 100
  },
  'Good3G': {
    'offline': false,
    'downloadThroughput': 1.5 * 1024 * 1024 / 8,
    'uploadThroughput': 750 * 1024 / 8,
    'latency': 40
  },
  'Regular4G': {
    'offline': false,
    'downloadThroughput': 4 * 1024 * 1024 / 8,
    'uploadThroughput': 3 * 1024 * 1024 / 8,
    'latency': 20
  },
  'WiFi': {
    'offline': false,
    'downloadThroughput': 30 * 1024 * 1024 / 8,
    'uploadThroughput': 15 * 1024 * 1024 / 8,
    'latency': 2
  }
};
(async () => {
  let keys = Object.keys(networkPresets);
  for (let key of keys) {
    let throttleConf = networkPresets[key];
    puppeteer.launch({ headless: false, args: ['--no-sandbox', '--headless', '--window-size=1920,1200'] }).then(async browser => {
      const page = await browser.newPage();
      let url = "https://www.educative.io/";
      const client = await page.target().createCDPSession();
      await client.send('Network.emulateNetworkConditions', throttleConf);
      let start = Date.now();
      await page.goto(url);
      let timeTaken = Date.now() - start;
      console.log(`time taken to load url ${url} with network throttle conf '${key}': '${JSON.stringify(throttleConf)}'=> ${timeTaken} ms`);
      await browser.close();
    });
  }
})();