Selenium as an API allows you to control a headless browser through a series of programs. It was created primarily for automated web testing, but due to its compatibility with JavaScript, it is also used for web scraping.

As websites have improved and upgraded, they have introduced more functions that depend on JavaScript to run.

Examples of such functions are bottomless pages and asynchronous loading. Using regular web scraping scripts would be a problem as they can’t scrape content found in JavaScript elements.

The only way would be to load the full page first. Selenium on the other hand can run web scraping even if the content is nested in JavaScript elements.

Selenium also brings versatility to the table. You can run it on different programming languages apart from java such as python, node.js, and Ruby.

You can also use selenium to control every major web browser such as chrome, internet explorer, and Firefox. This is in addition to the long-standing threads of problems and solutions concerning the library.

When using selenium, your actions aren’t limited to loading web pages. You can also perform other actions that allow you better interact with the website such as mouse clicks and filling forms.

Selenium controls headless browsers and so requires a lot of resources. This reduces its efficiency and creates a scene where better options are required. Even though puppeteer and playwright are controversially better options, selenium is still great for scraping a small number of pages that use JavaScript.

The most alluring features of selenium, in summary, are as follows:

• Selenium can easily handle AJAX and PJAX requests
• It can be used with JavaScript concepts

Also Read : How to Match Browser Location Settings to External IP Address

BeautifulSoup is a python based parsing library that allows you to extract data from a badly written web page. It structures an HTML or XML web page, gets the data you need from amongst the lot, and allows you to extract the required data in the right format.

However, it can crawl pages or make GET requests so it’s not all-encompassing.

BeautifulSoup is made up of different parsing tools such as html.parser, lxml, and HTML5lib. This way, you can try out different parsing methods to reap their benefits in different instances.

A huge pro of BeautifulSoup is its ease of use. with just a few lines of code, you can build a scraper. This doesn’t imply that it breaks easily either. And so BeautifulSoup is popular among developers for these reasons and others.

There is an online community with various solutions to different problems you may face during using this library.

Even though BeautifulSoup permits parallel requests, it isn’t easy to set up and still lags when compared to Scrapy in terms of speed.

So if you have a small web scraping task that doesn’t require huge data extraction, you can use BeautifulSoup.

The advantages of using BeautifulSoup in summary are:

• Ease to learn
• Community support to help with issues when they arise
• The documentation is comprehensive and allows for easy learning

Scrapy is a complete package when it comes to web scraping. It provides you with the tools you need to crawl web pages, download data and parse it, and then store it in the format of your choice.

Since Scrapy is based on python language, and also open-source, it's popular among developers for web scraping.

Scrapy supports both middleware and extensions as it was made to be extensible. This brings about great functionality to Scrapy scripts. You can also add your proxies, handle cookies and sessions, and control the crawl depth.

It also has an interactive console so you can be sure you have chosen the right expressions.

An alluring feature of Scrapy is its asynchronous way of handling and processing requests. This allows you to extract data with speed even if from multiple pages at once. So if you are interested in large scale scraping, this is a great option for you.

Bear in mind that the functionalities and features reduce its ease of use. so you will need to put in the time and effort to know your way around the tool. You will also require a headless browser for your java operations.

In summary, the features of Scrapy include:

• Its easily extensible
• It uses less memory and CPU storage
• Scrapy supports data extraction from HTML sources
• There is good support from the online community for developers
• With Scrapy, you can build a robust and efficient system that has a lot of functions
• It is fast
• It’s a portable library

Every library has its pros and cons, and so we must first compare them in their strengths and weaknesses before making a choice. When comparing selenium vs BeautifulSoup, the following are factors to consider.

Performance

One of the ways to compare selenium vs BeautifulSoup is the performance of both. Selenium is pretty effective and can handle tasks to a good extent. BeautifulSoup on the other hand is slow but can be improved with multithreading. This is a con of BeautifulSoup because the programmer needs to know multithreading properly.

Scrapy is faster than both as it makes use of asynchronous system calls. So it’s faster and performs better than other libraries.

Extensibility

BeautifulSoup is king when it comes to handling small projects with low-level complexity. This is because it works with simple and flexible codes. And so if you are new and want to perform web scraping quickly, BeautifulSoup is the library for you. Selenium is also great especially when you are dealing with a website that has a lot of features hinged on java. Note however that the data size when using selenium should be limited.

Scrapy allows for the execution of a robust and flexible project. This is thanks to the middleware that allows the addition of custom functionality. It’s great for use with big projects as you can easily transfer existing projects into another project.

Ecosystem

Both selenium and BeautifulSoup have a good ecosystem but do not allow easy use of proxies. This is one of the disadvantages of both libraries as it prevents the use of the libraries for complex projects.

Scrapy has a good ecosystem and allows you to use proxies to automate your web scraping tasks. That’s why it’s more ideal for use when you have complex projects as you can send multiple requests at once.

No matter your budget, you can comfortably use any of the libraries as they are all free and also open source. They also have a community of developers to support you as you use the library. Your choice of one over the other however depends on the project you have at hand.

If you have a complex task at hand, then Scrapy would be the best for you. its architecture allows it to handle complex web tasks. You can even extend its functionality if you choose.

BeautifulSoup is the best option for you if you have a small task at hand. All you need to do is install the request module and the HTML parser of your choice.

If the website you would be scraping from has a lot of JavaScript used, then selenium would come to your rescue.

Instead of looking for the best one when comparing selenium vs BeautifulSoup, and also Scrapy, you should learn them all. They all have their pros and cons and good knowledge of all will save you the stress of having to use just one for all your tasks.