Are you new to the world of harvesting data online? Then come in now to read our ultimate guide to Web Scraping, an automated process of harvesting data publicly available on the World Wide Web.
Companies, businesses, and researchers are increasingly knowing the importance of data in making educated guesses, drawing up mathematical predictions, making inferences, and carrying out sentimental analysis. We are in the golden age of data, and businesses will pay any amount to get their hands on data related to their businesses. Interestingly, the Internet is a huge library of data with textual data, graphical data, and audio files. All of these can be gotten from the web with a process known as web scraping.
How would you feel if you can automate the process of harvesting publicly available data online? That’s what web scraping came to make possible. You will be learning about web scraping in this article, including its legality, what it can be used for, and tools required in web scraping. Take this article to be an ultimate guide to Web Scraping for beginners because that’s what it is.
What is Web Scraping?
Web scraping is the use of automation script to extract data from websites. The automation script used for web scraping is known as a web scraper. While there are some already developed web scrapers in the market, most marketers involved in it custom develop their own web scrapers to take care of the peculiarities involved in their unique cases.
It is important I stress here that extracting data from websites by consuming a web API is not web scraping. A Web Application Application Interface (API) is a medium where applications communicate with other applications. Some websites do provide web APIs so that users can download data from their website without necessarily downloading unnecessary content that will add more load to their server.
Why Engaging in Web Scraping?
If a website provides an API for extracting data using automated means, why engage in Web Scraping then? Web APIs come with a lot of restrictions. They restrict you to certain data on a website and restrict the number of times you can request them.
With an API, you do not need to worry about all of these. Just send your request to the API URL with the required data, and you’ll get back the data you require. However, its restrictive nature leaves developers with no choice than to web scrape.
While websites like Twitter provides API for users to extract tweets and other user-generated data, other websites do not provide APIs for that. Web services like Instagram do not provide an API, and as such, if you need to harvest data from Instagram, you must make use of web scraping.
How Does Web Scraping Work?
Now that you know what web scraping is and why people engage in it, how does it work? I stated earlier that it is an automated process carried out with the use of an automation bot known as a web scraper. While the complexity of different web scrapers can make it difficult to reach a conclusion on how web scrapers work, we can reach a conclusion if we strip out the complexities and peculiarities, we can reach a valid conclusion as to how web scrapers work.
Is Web Scraping Legal?
When the term web scraping is mentioned, what comes into the mind of many is if it is legal. Well, while most websites frown at it, it is still legal. There had been numerous court cases where websites file lawsuits against businesses and individuals web scraping their web content. In most of the cases, the website filing the case end up losing.
This is because the information been scraped is publicly available on their website. However, you do not have to take my word for it. Before scraping any website, do contact a lawyer as the technicalities involved might make it illegal. But on a general note, web scraping is legal.
What is Web Scraping Used for?
Web scraping can be used for a variety of uses. While some that engage in it do it for business-related gains, some do it for educational purposes, while some for research as in the case of a government institution. Let take a look at some of the common use cases of web scraping.
Scraping Contact Information
Many Internet marketers use web scraping to harvest contain details of individuals. Contacts such as email addresses and phone numbers are being harvested every day from social media sites and online forums where people display their contact information. Have you seen people try to provide their email or phone number in obscure formats? They are trying to prevent web scrapers from accessing their information.
Sentimental Analysis is the use of natural language processing to discover the inclination of a piece of text. It is used extensively in finding the inclination of a buyer by analyzing his reviews. Political groups can use text scraped from Facebook groups and Tweeter discussions to detect if a particular group of people are for them or against them.
Price Comparison and Monitoring
One of the key use of web scraping is for monitoring the prices of commodities. This could be the prices of products you sell on Amazon or your competitors’ products – so you can set a competitive price. It could also be the price of a stock, cryptocurrency, or even forex. Just name it, you can also monitor the price of any commodity publicly available online.
The job of a data scientist is to make sense out of data, which can be both in a structured or unstructured format. A lot of these are available online. I have scraped a lot of health-related data from the World Health Organization (WHO) website.
I have had to scrape football history data too for some predictive models in the past too. Governments, companies, and private individuals do research with scraped data from online sources.
Social Media Scrapping
Another use of web scraping is social media scraping. Social media scraping can be used to gather information about users and their information. Content creators use web scraping to detect what’s trending on different social media platforms so that they can create content related to the trending contents.
Search Engine Optimization
Web scraping is used extensively in the area of SEO. It is used for monitoring page ranging as well as scraping Google for keyword related data and expired domains. Internet marketers also use Web Scraping to carry out site audits using tools like Screaming Frog.
- Why use SEO Proxies With SEO software
- SEO Proxies for Scraping Search Engines without Block and Captchas!
Popular Web Scraping Tools
There are many tools you can use for web scraping. While some of them are paid and provide you premium support, our focus on this article will be on the free tools available to you for web scraping. There are basically two types of tools –the ones for coders and the ones for non-coders.
Web Scraping Tools for Coders
As a coder, the tools available to you are the tools you can incorporate with much larger systems to build complex systems. Unlike in the case of tools for non-coders, which are standalone, most tools used by coders are to be incorporated into a project. For Python developers, the two most popular tools include Scrapy, a web crawling and scraping framework, and BeautifulSoup. BeautifulSoup is not for scraping; it is for parsing already scraped HTML document. Selenium is extensively being used for controlling browsers in Python too.
- Scrapy Vs. Beautifulsoup Vs. Selenium for Web Scraping
- Selenium Proxy Setting & How to Setup Proxies on Selenium
Web Scraping Tools for Non-coders
If you do not have programming skills, it is important you know that there are scraping tools available to you. These tools require no coding at all. Using the user interface provided, you can configure the tools to scrape the required data for you. ParseHub and Octoparse are some of the scraping tools that require no coding. You can use them for free, but there are some limitations. Paying for a subscription unlocks their full potentials.
The Role of Proxies in Web Scraping
Regardless of if you are using tools for the coders or non-coders, proxies have their place in the world of web scraping. Websites do not want their data scraped, especially when done in an automated way.
They put in place, systems that checkmates botting, which uses one's IP address to track the number of requests sent within a period of time. If requests sent from a particular IP Address exceeds the normal limit, access to the website is blocked. By making use of proxies, the anti-spam system is deceived, since the bot will be sending requests through different IPs.
The best proxies to use for web scraping are rotating proxies. High rotating proxies are the best when you do not need to maintain a session. However, for websites that require a login and need session maintained, you need proxies that changes IP address after a specified period of time.
- How To Generate A Random IP Address For Each Session
- How to Use Rotating Proxy API and Proxy lists with CURL for data mining
The Dark Sides of Web Scraping
Looking at the above, you might think that web scraping has no dark sides. Well, it does. The number one problem associated with web scraping is that it is the means through which spammers and scammers get the contact of their victims.
Also important is the fact that using a web scraper sends many requests in a short period of time, which then to overloads the server of websites and increases their running cost – while they have nothing good in return.
FAQs about Web Scraping
Differences Between Web Scraping and Using API
Using a web API comes with a lot of limitations and, in some instances, requires payment. However, in the case of web scraping, it is completely free and devoid of limitations. You just have to do extra work to get the required data yourself using a web scraper. For web APIs, you require no tool; the HTTP request you send returns the required data.
Is Web Scraping Legal?
Yes, web scraping is legal, even though many sites do not support it. You can scrape Amazon and LinkedIn without any problem. However, contact your lawyer as technicalities involved might make it illegal.
Are Proxies Must for Web Scraping?
No, proxies are not a must. However, for complex websites with strict anti-spam systems, you require them if you need to scrape a lot of content. Rotating proxies are the best for web scraping.
Web scraping, no doubt, has its place in Internet marketing and research. It has come to stay, and with it, you can scale up your business effortlessly. However, when doing it, it is advisable you throttle your request timing so that you do not overload the server of the website you are scraping data from. You also need to know that proxies are required when web scraping, and most tools require them.