Puppeteer: accessing SSL cert data

certpinning.js

const puppeteer = require('puppeteer');

process.on('unhandledRejection', (reason, p) => {
  console.error('Unhandled Rejection at: Promise ', p, ' reason: ', reason);
  process.exit(3);
});

(async () => {
  let browser;
  let exitCode = 0;

  try {
    browser = await puppeteer.launch({headless: false, devtools: true});
    const page = await browser.newPage();

    const client = await page.target().createCDPSession();
    await client.send('Network.enable');

    page.on('response', async (res) => {
      if (res.securityDetails() != null) {
        console.info(await page._client.send('Network.getCertificate', {origin: res.url()}));
      }
    });

    await page.goto('https://www.chase.com/', {
      waitUntil: 'networkidle2',
      timeout: 3000000
    });
  } catch (e) {
    console.error('Got exception', e);
    exitCode = 1;
  } finally {
    if (browser != null) {
      await browser.close();
    }
    process.exit(exitCode);
  }
})();