Node.js and Puppeteer Web Scraping: Difference between revisions

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// Count div elements
// Count buttons
const buttons = await page.$$('button');
const buttons = await page.$$('button');
console.log("found buttons:", buttons.length);
console.log("found buttons:", buttons.length);

Revision as of 10:22, 2 September 2025


Puppeteer uses headless Chrome browser instance but making it visible helps to show what you are doing. Also, you can use DevTools (F12) the see what is happening.

This setup has been used for Windows but should also be possible for Linux.

I first tried "Puphpeteer", which is a PHP library that is made on top of Puppeteer. This however, turns out to result in a wobbly stack of badly maintained components.

Generally

Windows install of Node.js

The Node.js installer (msi) has an option to install dependencies, you can try it but it is quite terrible.

  • PowerShell is used during installation
  • Chocolatey Package manager https://chocolatey.org/install is installed and used for further installation
  • Visual Studio Build Tools 2022 (for its 64 bit C++ compiler) is installed
  • Python 3.13.7 is installed
  • Node.js is installed with Node.js package manager npm

There are other options, this is my selection.

Start new Node.js project

Start terminal

cd D:\Programs\Nodejs\
mkdir puppeteer-project
cd puppeteer-project
npm init

Install Puppeteer

(in terminal)

cd puppeteer-project
npm install puppeteer

Code

import puppeteer from 'puppeteer';

function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}

(async () => {
	
	// Open a browser {headless:false} means the browser will be visible
	const browser = await puppeteer.launch({headless: false});
	const page = await browser.newPage();

	// Navigate to a URL
	await page.goto('https://duckduckgo.com/', {delay: 500});

	// Navigate to a file (example)
	//page.goto('file:///'+import.meta.dirname+'/test.html');

	// Set screen size
	await page.setViewport({width: 1300, height: 1000});

	// Wait for an element using a CSS selector, 
	const selector1 = 'input[id="searchbox_input"]';
	await page.waitForSelector(selector1);
	
	// Select and type
	await page.type(selector1, 'Node.js puppeteer examples', {delay: 5});
	// Press Enter
	await page.keyboard.press('Enter', {delay: 1000}); 


	// Count buttons
	const buttons = await page.$$('button');
	console.log("found buttons:", buttons.length);	

	//Click button with text "More results"
	await page.$$eval('button', buttons => {
			for (const btn of buttons) {
				if ( btn.innerText.toLowerCase().includes('more results') ) {
					btn.scrollIntoView();
					btn.click();
					break;
				}
			}
		}
	);

	// Show url
	const url = await page.evaluate(() => {
		return window.location.href;
	}); 
	console.log("url:", url);

	// Show local storage
	const localStorage = await page.evaluate(() => {
		return localStorage;
	});
	console.log("localStorage:", JSON.stringify(localStorage));

	// Show cookies
	const cookies = await browser.cookies();
	console.log("cookies:", cookies);

	// Wait 5mins
	console.log("Press CTRL+C to close ..");
	await sleep(5*60*1000);

	// Close browser
	await browser.close();
})();

Execute

(in terminal)

cd D:\Programs\Nodejs\
cd puppeteer-project
node app-test.js