JavaScript Web Scraping: What You Need to Know

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Many people choose to use Python for data extraction, and not without a good reason. If you want to get something done, it is best to get it done in the most accessible way in a world where time and resources mean money. It explains the rush towards using Python and its flock of libraries and frameworks for web scraping.

But JavaScript has always been an excellent language for writing web scraping codes as well. And with the introduction of NodeJS, the language has become more popular and, its application, more readily acceptable.

And since having multiple alternatives never hurts anyone, JavaScript scraping is here to stay with more and more people using it.
What is Web Scraping.

Web scraping, also commonly called web data extraction or web harvesting is defined as the process of collecting both structured and unstructured user data in varying amounts from multiple websites.

The process is mainly automated and finds a way to interact with the target website, retrieve the necessary data, parse it, and then save it on the client’s computer in an easily readable format, e.g., a spreadsheet.

The purpose of doing this is to have enough valuable data to drive business decisions, and some of the things a business can do with the collected data include:

Purpose of Javascript

⦁ Brand monitoring and protection
⦁ Monitoring competition and price
⦁ Conducting market research and analysis

Main Programming Languages Used in Web Scraping

There are several languages used in web scraping. But the choice of which of the languages to use should be based, first, on what your needs are and, next, on which of the languages you are great at. If you want to scrape a PHP website you can use PHP web scraper. And when trying to choose the best web scraping language, it is believed that the shortlist of questions below could help you make the right choice:

⦁ How flexible is the language?
⦁ How practical is any given crawling session?
⦁ How easy is it to write and code in that language?
⦁ Is the scraping script written in that language accessible to both scale and maintain?
⦁ Does the language have an operational ability to handle a vast database?

Best Web Scraping Languages

The trick here is that if you can find satisfying answers to the above question regarding a language, then that language is web scraping worthy. Python and JavaScript NodeJS are considered the two best web scraping languages because they answer the above questions well.

Python

Python is, by all standards, the most popular web scraping language because it does not only make it easy to scrape websites automatically but also makes the entire process smooth and seamless.

Python is also the easiest to learn, and a typical web scraping Python script can be written in only a few lines. And within this language alone, you will find both the tools to extract data and parse or return it.

Some of the important Python tools widely employed in web scraping include libraries such as BeautifulSoup and Selenium or complete frameworks.

JavaScript NodeJS

JavaScript was built originally to handle data manipulation but not directly extract it. NodeJS, which was later developed with many features and to assist in the JavaScript runtime environment, is essentially what makes it possible to perform JavaScript web scraping.

Simply put, JavaScript is a programming language that can run on any web browser, and NodeJS is what interprets the language and provides it with the required environment to be used appropriately.

When combined, they can be used for asynchronous web scraping. Meaning you can scrape multiple websites at the same time.
Some of the features offered by this package include:

Features of Javascript web scraping

⦁ ExpressJS: a highly flexible framework that can be used on both mobile and web applications
⦁ Request, Request-promise, and Axios: very simple HTTP clients used for making HTTP requests
⦁ Cheerio: a library JavaScript NodeJS uses in traversing the Document Object Model (DOM), extracting data from websites as well as parsing responses

Why JavaScript Is a Suitable Choice for Web Scraping

Web scraping with JavaScript is an automatic process that can be done on many websites at once. And below are the steps by which the process is done:

⦁ First, you find the webpage you intend to scrape
⦁ Next, you make an HTTP request to extract the data
⦁ The data is extracted and parsed to your device
⦁ Finally, you save the extracted data usually in JSON format

That said, there are three major reasons why JavaScript is considered suitable for web scraping. First, JavaScript can run any browser, meaning you do not need to choose any specific web browser when you want to extract data.

Secondly, JavaScript NodeJS can be easily extended to run on multiple web pages and extract data from various sources at once. This is necessary if you want to save both time and energy during web scraping.

Lastly, the language can easily handle any form of debugging necessary to ensure effective web scraping. It can also use the set () function to prevent several duplicates of the same data, making JavaScript web scraping an efficient and straightforward process easily.

Conclusion

JavaScript is an excellent language for web scraping and even offers a suitable alternative to using Python, especially if you are looking to try something different.

However, the choice of which web scraping language to use should be based entirely on what you wish to achieve and which of the languages you are already vast in.