Browser automation with Puppeteer

Puppeteer is a headless browser for automating browser tasks. Here's the list of some of the features:

• Turn off headless mode

  const browser = await puppeteer.launch({
    headless: false
    // ...
  });

• Resize the viewport to the window size

  const browser = await puppeteer.launch({
    // ...
    defaultViewport: null
  });

• Emulate screen how it's shown to the user via the emulateMediaType method

  await page.emulateMediaType('screen');

• Save the page as a PDF file with a specified path, format, scale factor, and page range

  await page.pdf({
    path: 'path.pdf',
    format: 'A3',
    scale: 1,
    pageRanges: '1-2',
    printBackground: true
  });

• Use preexisting user's credentials to skip logging in to some websites. The user data directory is a parent of the Profile Path value from the chrome://version page.

  const browser = await puppeteer.launch({
    // ...
    args: [
      '--user-data-dir=C:\\Users\\<USERNAME>\\AppData\\Local\\Google\\Chrome\\User Data'
    ]
  });

• Use Chrome instance instead of Chromium by setting up the executable path from the chrome://version URL. Close Chrome browser before running the script

  const browser = await puppeteer.launch({
    executablePath: 'C:\\Program Files\\Google\\Chrome\\Application\\chrome.exe'
    // ...
  });

• Wait for a specific selector to be loaded. You can also provide a timeout in milliseconds

  await page.waitForSelector('.success', { timeout: 5000 });

• Manipulate with a specific element and click on some of the elements

  await page.$eval('#header', async (headerElement) => {
    // ...
    headerElement
      .querySelectorAll('svg')
      .item(13)
      .parentNode.click();
  });

• Manipulate with multiple elements

  await page.$$eval('.some-class', async (elements) => {
    // ...
  });

• Wait for navigation (e.g., form submitting) to be done

  await page.waitForNavigation({ waitUntil: 'networkidle0', timeout: 0 });

• Trigger hover event on some of the elements

  await page.$eval('#header', async (headerElement) => {
    const hoverEvent = new MouseEvent('mouseover', {
      view: window,
      bubbles: true,
      cancelable: true
    });
    headerElement.dispatchEvent(hoverEvent);
  });

• Expose a function in the browser and use it in $eval and $$eval callbacks (e.g., simulate typing using the window.type function)

  await page.exposeFunction('type', async (selector, text, options) => {
    await page.type(selector, text, options);
  });
  await page.$$eval('.some-class', async (elements) => {
    // ...
    window.type(selector, text, { delay: 0 });
  });

• Expose a variable in the browser by passing it as the third argument for $eval and $$eval methods and use it in $eval and $$eval callbacks

  await page.$eval(
    '#element',
    async (element, customVariable) => {
      // ...
    },
    customVariable
  );