Javascript is a widely-used programming language and an ever-increasing number of websites use JavaScript to fetch and render user content. While there are various tools available for web scraping, a growing number of people are exploring Javascript web scraping tools.

To carry out your web scraping projects, you need to familiarize yourself with web scraping tools to choose the right one. We will walk through open source Javascript tools and frameworks that are great for web crawling, web scraping, parsing, and extracting data.

Open Source Javascript Web Scraping Tools and Frameworks

After reading this you should be a little bit more familiar with web scraping. The first way to scrape Ajax website with Java that we are going to see is by using PhantomJS with Selenium and GhostDriver. PhantomJS is a headless web browser based on WebKit ( used in Chrome and Safari).

Mar 02, 2021 The simplest way to get started with web scraping without any dependencies is to use a bunch of regular expressions on the HTML string that you fetch using an HTTP client. But there is a big tradeoff. Regular expressions aren't as flexible and both professionals and amateurs struggle with writing them correctly. Browse other questions tagged javascript beginner jquery html or ask your own question. The Overflow Blog Podcast 323: A director of engineering explains scaling from dozens of. If you need a web scraping tool in Javascript and JQuery. Puppeteer is a Node library which provides a powerful but simple API that allows you to control Google’s headless Chrome browser. A headless browser means you have a browser that can send and receive requests but has no GUI.

Note: All details in the table above are current at the time of writing this article.

Apify SDK

Apify SDK is a Node.js library which is a lot like Scrapy positioning itself as a universal web scraping library in JavaScript, with support for Puppeteer, Cheerio, and more. With its unique features like RequestQueue and AutoscaledPool, you can start with several URLs and then recursively follow links to other pages and can run the scraping tasks at the maximum capacity of the system respectively.

Requirements – The Apify SDK requires Node.js 10.17 or later
Available Selectors – CSS
Available Data Formats – JSON, JSONL, CSV, XML, Excel or HTML

Pros

• Supports any type of website
• Best library for web crawling in Javascript we have tried so far.
• Built-in support for Puppeteer and Cheerio

Installation
Add Apify SDK to any Node.js project by running:

Best Use Case

Apify SDK is a preferred tool when other solutions fall flat during heavier tasks – performing deep crawls, rotating proxies to mask the browser, scheduling the scraper to run multiple times, caching results to prevent data prevention if the code happens to crash, and more. Apify handles such operations with ease but it can also help to develop web scrapers of your own in Javascript.

Node SimpleCrawler

Simplecrawler is designed to provide a basic, flexible, and robust API for crawling websites. It was written to archive, analyze, and search some very large websites and can get through hundreds of thousands of pages and write large volumes of data without issue. It has a lot of useful events that can help you track the progress of your crawling process. This crawler is extremely configurable and there’s a long list of settings you can change to adapt it to your specific needs.

Requirements – Node.js 8.0+

Pros

• Respects robot.txt rules
• Highly configurable
• Easy setup and installation

Cons

• Does not download the response body when it encounters an HTTP error status in the response
• No promise support
• May get invalid URLs because of its brute force approach

Installation
To install simplecrawler type the command:

Best Use Case

If you need to start off with a flexible and configurable base for writing your own crawler

NodeCrawler

Nodecrawler is a popular web crawler for NodeJS, making it a very fast crawling solution. If you prefer coding in JavaScript, or you are dealing with mostly a Javascript project, Nodecrawler will be the most suitable web crawler to use. Its installation is pretty simple too. JSDOM and Cheerio (used for HTML parsing) use it for server-side rendering, with JSDOM being more robust.

Requires Version – Node v4.0.0 or greater
Available Selectors – CSS, XPath
Available Data Formats – CSV, JSON, XML

Pros

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• Easy installation

Cons

• It has no Promise support

Installation
To install this package with npm:

Best Use Case

If you need a lightweight web crawler that combines efficiency and convenience.

PJScrape

PJscrape is a web scraping framework written in Python using Javascript and JQuery. It is built to run with PhantomJS, so it allows you to scrape pages in a fully rendered, Javascript-enabled context from the command line, with no browser required. The scraper functions are evaluated in a full browser context. This means you not only have access to the DOM, but you also have access to Javascript variables and functions, AJAX-loaded content, etc.

Requires Version – Node v4.0.0+, PhantomJS v.1.3+
Available Selectors – CSS
Available Data Format – JSON

Pros

• Easy installation and setup for more than one scraper
• Suitable for recursive crawling

Cons

• Poor documentation

Jquery Web Scraping Examples

Installation
To install this package with npm:

Best Use Case

If you need a web scraping tool in Javascript and JQuery

Puppeteer

Puppeteer is a Node library which provides a powerful but simple API that allows you to control Google’s headless Chrome browser. A headless browser means you have a browser that can send and receive requests but has no GUI. It works in the background, performing actions as instructed by an API. You can truly simulate the user experience, typing where they type and clicking where they click.

A headless browser is a great tool for automated testing and server environments where you don’t need a visible UI shell. For example, you may want to run some tests against a real web page, create a PDF of it, or just inspect how the browser renders a URL. Puppeteer can also be used to take screenshots of web pages visible by default when you open a web browser.

Puppeteer’s API is very similar to Selenium WebDriver, but works only with Google Chrome. Puppeteer has a more active support than Selenium, so if you are working with Chrome, Puppeteer is your best option for web scraping.

Requires Version – Node v6.4.0, Node v7.6.0 or greater
Available Selectors – CSS
Available Data Formats – JSON

Pros

• With its full-featured API, it covers a majority of use cases
• The best option for scraping Javascript websites on Chrome

Cons

• Only available for Chrome/Chromium browser
• Supports only JSON format

Installation
To install Puppeteer in your project run:

This will install Puppeteer and download the recent version of Chromium browser to run the puppeteer code. By default, puppeteer works with the Chromium browser but you can also use Chrome. You can also use the lightweight version of Puppeteer – puppeteer core. To install type the command:

Best Use Case

• If you need to test the speed, performance, responsivenes, and UI of a website.
• If you are using Chrome, Puppeteer is your best option for web scraping.
• If the information you want is generated using

Playwright

Playwright is a Node library to automate multiple browsers with a single API. It enables cross-browser web automation that is ever-green, capable, reliable, and fast. Playwright was created to improve automated UI testing by eliminating flakiness, improving the speed of execution, and offering insights into the browser operation.

Download xcode not from app store android. Playwright is very similar to Puppeteer in many respects. The API methods are identical in most cases, and Playwright also bundles compatible browsers by default. Playwright’s biggest differentiating point is cross-browser support. It can drive Chromium, WebKit, MS Edge, and Firefox.

A noteworthy difference is that Playwright has a more powerful browser context feature than Puppeteer. This lets you simulate multiple devices with a single browser instance.

Requires Version – Node.js 10.15 or above.
Available Selectors – CSS
Available Data Formats – JSON

Pros

• Cross Browser support
• Detailed documentation

Con

• They have only patched the WebKit and Firefox debugging protocols, not the actual rendering engine

Installation
To install the package:

This installs Playwright and browser binaries for Chromium, Firefox, and WebKit. Once installed, you can use Playwright in a Node.js script and automate web browser interactions.

Best use case

If you need an efficient tool as good as Puppeteer to perform UI testing but across multiple browsers, you should use Playwright.

Cheerio

Cheerio is a library that parses raw HTML and XML documents and allows you to use the syntax of jQuery while working with the downloaded data. With Cheerio, you can write filter functions to fine-tune which data you want from your selectors. If you are writing a web scraper in JavaScript, Cheerio API is a fast option that makes parsing, manipulating, and rendering efficient.

It does not – interpret the result as a web browser, produce a visual rendering, apply CSS, load external resources, or execute JavaScript. If you require any of these features, you should consider projects like PhantomJS or JSDom.

Requirements – Up to date versions of Node.js and npm
Available Selectors – CSS

Pros

• Parsing, rendering and manipulating documents is very efficient
• Flexible, Easy to Use
• Very fast (Preliminary end to end benchmarks suggests its 8x faster than JSDOM)

Cons

• Does not fare well for dynamic Javascript websites

Installation
To install the required modules using NPM, simply type the following command:

Best Use Case

If you need speed, go for Cheerio.

These are just some of the open-source javascript web scraping tools and frameworks you can use for your web scraping projects. If you have greater scraping requirements or would like to scrape on a much larger scale it’s better to use web scraping services.

If you aren’t proficient with programming or your needs are complex, or you need large volumes of data to be scraped, there are great web scraping services that will suit your requirements to make the job easier for you.

You can save time and get clean, structured data by trying us out instead – we are a full-service provider that doesn’t require the use of any tools and all you get is clean data without any hassles.

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Turn the Internet into meaningful, structured and usable data

Today more and more websites are using Ajax for fancy user experiences, dynamic web pages, and many more good reasons.Crawling Ajax heavy website can be tricky and painful, we are going to see some tricks to make it easier.

Prerequisite

Before starting, please read the previous articles I wrote to understand how to set up your Java environment, and have a basic understanding of HtmlUnit Introduction to Web Scraping With Java and Handling Authentication.After reading this you should be a little bit more familiar with web scraping.

Setup

The first way to scrape Ajax website with Java that we are going to see is by using PhantomJS with Selenium and GhostDriver.

PhantomJS is a headless web browser based on WebKit ( used in Chrome and Safari). It is quite fast and does a great job to render the Dom like a normal web browser.

• First you'll need to download PhantomJS
• Then add this to your pom.xml :

and this :

##PhantomJS and Selenium

Now we're going to use Selenium and GhostDriver to “pilot” PhantomJS. Paintbrush download for windows.

The example that we are going to see is a simple “See more” button on a news site, that perform a ajax call to load more news.So you may think that opening PhantomJS to click on a simple button is a waste of time and overkilled ? Of course it is !

The news site is : Inshort

As usual we have to open Chrome Dev tools or your favorite inspector to see how to select the “Load More” button and then click on it.

Now let's look at some code :

That's a lot of code to setup phantomJs and Selenium !I suggest you to read the documentation to see the many arguments you can pass to PhantomJS.

Note that you will have to replace /usr/local/bin/phantomjs with your own phantomJs executable path

Then in a main method :

Here we call the initPhantomJs() method to setup everything, then we select the button with its id and click on it.

The other part of the code count the number of articles we have on the page and print it to show what we have loaded.

We could have also printed the entire dom with driver.getPageSource()and open it in a real browser to see the difference before and after the click.

I suggest you to look at the Selenium Webdriver documentation, there are lots of cool methods to manipulate the DOM.

I used a dirty solution with my Thread.sleep(800) to wait for the Ajax call to complete.It's dirty because it is an arbitrary number, and the scraper could run faster if we could wait just the time it takes to perform that ajax call.

There are other ways of solving this problem :

If you look at the function being executed when we click on the button, you'll see it's using jQuery :

This code will wait until the variable jQuery.active equals 0 (it seems to be an internal variable of jQuery that counts the number of ongoing ajax calls)

If we knew what DOM elements the Ajax call is supposed to render we could have used that id/class/xpath in the WebDriverWait condition :

Conclusion

So we've seen a little bit about how to use PhantomJS with Java.

The example I took is really simple, it would have been easy to emulate the request. A great tool to intercept requests and reverse-engineer back-end APIs is Charles proxy.

But sometimes when you have tens of Ajax calls, and lots of Javascript being executed to render the page properly, it can be very hard to scrape the data you want, and PhantomJS/Selenium is here to save you :)

Next time we will see how to do it by analyzing the AJAX calls and make the requests ourselves.

If you want to know how to do this in Python, you can read our great 👉 python web scraping tutorial.

Jquery Web Scraping

As usual you can find all the code in my Github repo

Client Side Web Scraping

Rendering JS at scale can be really difficult and expensive. This is exactly the reason why we started ScrapingBee, a web scraping api that takes care of this for you.

Jquery Web Scraping Tutorial

It will also take car of proxies and CAPTCHAs, don't hesitate to check it out, the first 1000 API calls are on us.