Understanding the basic use of the command line has become optional for most computer users. This is because everything is hidden behind excellent, easy-to-understand user interfaces.
This means most users don’t need to learn the command-line unless you’re a coder whose work requires interaction with the command line. One of the most popular command-line interface tools is the Curl application.
The cURL tool is a powerful multipurpose tool. Here, we’ll learn more about this application and how you can use it for Web Scraping. But before we get into the how-to, let’s have a brief overview of the application.
What is cURL?
Client URL (cURL) is an open-source command-line utility developed to facilitate the transfer of data to and from web servers.
Simply put, it facilitates network communication with web servers, making it suitable for web Scraping.
Being a CLI application, you have to use it from the command line, which may sound challenging but is simple once you get used to it.
Why Use cURL for Web Scraping?
1. Versatility
cURL is available on nearly all operating systems, so you don’t need a virtual machine to use on an OS. Even more impressive is that it comes pre-installed on most operating systems.
And if not installed, all you need is a command-line and network connectivity to install it. cURL also supports a wide variety of protocols, including HTTP, FTP, and FILE.
2. Utility
cURL is a lightweight utility that you will find easy to use when web scraping. All you need to do to use it is go through the documentation and continuously practice how to use it.
3. Detailed
The cURL application is verbose. This means it provides all the information you need about what you are sending or requesting to and from web browsers.
This feature proves useful for troubleshooting as you can easily spot errors in the web scraping process.
Web Scraping Using cURL and Proxies
With just a single line of cURL command, you can easily get the content of a full web page. Although you won’t have problems with small-scale web scraping, increasing the number of requests can trigger anti-bot systems.
These are systems that websites use to protect themselves, and activating them may lead to IP bans and you may not be able to access the website. This is where proxies come in.
A datacenter proxy network acts as a middleman between you and the website. The website will no longer see your IP address, allowing you to scrape the web anonymously and with a reduced risk of getting blocked.
1. Setting Up cURL
To use cURL to scrape the web, you need to initiate the cURL function. The simplest command you can use is curl www.webpage.com, where pressing the enter key prints on the content of the www.webpage.com page. This will get you the full content in HTML, and not just what is visible to you.
2. Find the Required Data
After downloading the content of the web page, and printing it to the console, you need to parse it out and find the data that you need.
For this, you need to create a small function to scrape data from between strings, such as tags. In the cURL documentation site, you also have a list of options that show the actions that you can perform on the data you have received.
3. Saving Data
You can save the content that you have downloaded in a file using cURL. There is the -o method, which allows you to add a filename where the URL will be saved. It should come before the name of the webpage.
4. Scraping Multiple Data Points
Scraping a single piece of data from a web page is normal. However, you can expand your knowledge and skills by learning how to scrape data from multiple points.
You can do this by searching for a general category of items instead of a single value. By feeding the resulting URL into the scraping script, you will get a page with a list of all the items from different data points that you want to scrape.
There is a lot to learn about cURL and how it can help you interact with servers on the internet during web scraping. You can utilize the cURL documentation page as a guide to effective use of the application.
Mastering it will help you realize how powerful and functional it can be in simplifying your work.
In this article, you learned how to use cURL (client URL) for web scraping. cURL (client for URL) is a popular, open-source command-line tool for transferring information (data) to and from a web server using the URL syntax.
It is often pre-installed on the systems. We can easily instal it on the command line. The client for URL provides a detailed control over HTTP requests, so we can handle all possible swift requests easily.
The cURL works on both HTTP and FTP protocols to download and upload files. It provides an easy way to upload files when you are maintaining a website.
The post How to Use cURL for Web Scraping appeared first on Scientech Easy.
