Web scraping lets you extract data from websites so that you can analyze the collected data to perform several tasks like:
Every business, whether big or small, should use web scraping to achieve their business goals.
JavaScript is a high-level programming language used to perform complex web scraping tasks along with Node.js that allows the execution of JavaScript code outside a web browser.
In this article, we will learn how you can build a web scraper using JavaScript and Node.js but first, let’s understand how web scraping works and some other essentials related to web scraping. At the end of the article, we will discuss some of the best web scraping tools to make your scraping task much more manageable.
Ready? Let’s begin!
Web scraping is also known by the names data scraping, data extraction, and web harvesting. It is a technique of automating extracting data from websites and storing it in a format for further analysis.
The web scraping process works in two ways:
A proxy server is used to mask your IP address so that the target websites can’t locate and ban your IP. A proxy acts as an intermediary between your computer and the target website. The target website sees the proxy server IP address as the primary IP addresses allowing you to browse the web anonymously.
You should always use a proxy server for scraping because web scraping is an activity that can easily result in getting your IP blacklisted. Websites have mechanisms like anti-scraping tools and JavaScript checks to prevent scraping programs from accessing their website. When you try to use your scraping program to visit their website, they can easily detect the presence of a bot and blacklist your IP address.
When you use a proxy, all the requests initiated by your scraping program goes through the proxy server. It is always recommended to choose residential proxies because they offer the highest level of anonymity. Moreover, the proxy offers you a collection of IP addresses and uses an IP rotation technique that changes the IP address associated with every browsing request. The anti-scraping tools allow browsing websites because the requests come from different locations and mimic regular user activity.
JavaScript is a modern programming language that adds interactive elements to a website. JavaScript is not a program that can interact directly with your computer. It interacts with your browser’s JavaScript engine and runs the code.
However, when you use Node.js runtime environment with JavaScript, you enable it to run scripts on both the client-side and server-side.
Here are the steps for web scraping using JavaScript and Node.js:
$ mkdir scraper && cd scrapper
$ npm init -y
$ npm install –save axios cheerio
const siteUrl = "https://addurlyouwishtoscrape.com/";
const axios = require("axios");
const fetchData = async () => {
const result = await axios.get(siteUrl);
return cheerio.load(result.data);
};
const fs = require("fs");
const getResults = require("../scraper");
(async () => {
let results = await getResults();
let jsonString = JSON.stringify(results);
fs.writeFileSync("../output.json", jsonString, "utf-8");
})();
That’s it! These are the steps you need to follow to scrape any website using Json.js.
There are several other ways to build a web scraper apart from JavaScript and Node.js. These methods are explained as follows:
You can use Python for web scraping. It is a high-level programming language that is best for scraping. Selenium is a Python library that helps to automate web browsers to do several tasks. All you need to do is to install the Selenium and then access the website using Python. You need to locate the element XPath to scrape the exact element.
Puppeteer is a node library to control headless Chrome. The Google Chrome development team manages it. You can use Puppeteer to automate form submissions or generate screenshots of pages. To start using Puppeteer, you first need to install it. You can combine Node.js with Puppeteer to scrape a website. Make sure to use a Proxy in Puppeteer.
If you are looking to build web scrapers with the least coding, then some tools can be used to handle browsers and captchas with a simple API call.
Here are the top tools for web scraping:
Web scraping is essential for every business. There are different ways to scrape the web. You can use JavaScript to prepare data mining programs according to your business needs, or you can use the power of automatic tools to copy the data of your choice. No matter which method you choose for data harvesting, make sure to combine it with a proxy server’s power to hide your IP. Anonymous web scraping will give you faster results and keep your business reputation safe.
