Web Scraping – Essence, Methods, Software

In this article, we will delve into one of the key concepts related to managing or working with websites – web scraping.

So, the term “parsing” comes from the word “parse,” which means “structure, analysis.” Hence, it becomes clear what website parsing is and why it is needed. Website parsing is the targeted collection of open data from a specific resource and its structuring.

In essence, scraping is a form of copying where data from a website is collected into a central local database or spreadsheet for extraction or analysis. There are many solutions that allow you to customize web scraping—from the data format on the site to geolocation.

Goals and Objectives of Web Scraping

The main goal of web scraping, as mentioned, is copying data from websites—for example, from competitors. It is one of the effective competitive intelligence tools used by many global and Russian companies: M.Video, Citilink, Svyaznoy, and others.

To understand what web scraping is, let’s look at a few cases. For example, you sell furniture and have a good website with high customer traffic, sales, and updates. But your site becomes increasingly cluttered and pages load slower. You need to figure out which files are unused and what duplicate documents and images have accumulated. All this “junk” on the site needs to be identified and cleaned to restore speed and usability.

Another example: you launched a website selling fishing gear. But a huge workload remains—you need to fill in hundreds of product cards, which will take a lot of time and effort. You consider doing it manually inefficient, but you have another site with similar products in mind. In this case, it is enough to analyze the product descriptions on that site, tweak them a bit, and also address your own site’s promotion tasks.

Important caveat! When scraping websites, you may encounter personal data of users or the site owner. To avoid unpleasant consequences, you should inform them that you have analyzed this information. Otherwise, you could run afoul of Article 273 of the Russian Criminal Code, which addresses illegal access to computer information.

How Does Web Scraping Work?

To understand the principle of web scraping, let’s discuss the theory. Specialized web scraping software sends numerous requests from your IP to the target website. Metaphorically, it’s like a child running through a hallway and knocking on every door. The reaction can vary. For example, the child might be scolded and thrown out of the building.

Similarly, on the site you’re interested in, they can ban (block) your IP address. As a result, you lose access, which can only be restored using network virtualization tools. Hence, a recommendation: use a VPN connection for web scraping. Additionally, you need to consider the functionality of the scraping program. It should be able to:

1. select the file type for analysis;
2. change the user-agent;
3. build the site tree;
4. separate duplicate content;
5. choose proxies and VPN;
6. have meta robots.

How to Choose a Web Scraping Program?

Web scraping software is an area of active development. Modern solutions range from those requiring human effort to fully automated ones that can convert websites into structured information. The simplest way to scrape is to manually copy and paste data from a web page into a text file or spreadsheet. This is often the only way to collect data when the site is protected from automated scraping.

Today, you can find many web scraping programs online. Some are free and open source (see github.com), others require payment (closed source), and some are browser extensions. Moreover, if you have the knowledge, skills, and desire, you can write your own scraping software. Let’s discuss each type in detail.

Open Source Web Scraping Software

Scraping programs in this category require certain knowledge, including English. For example, if you want to access data from a particular resource, simply enter the site name in the search bar on github.com. For every popular platform, there is scraping software available. Among universal solutions for less popular sites, we can recommend:

1. Drupal – a module for parsing HTML pages of websites;
2. Parsedown – a PHP parser;
3. Sitemap – a link parser used to create site search.

Closed Source Web Scraping Software

Paid scraping programs are more convenient and easier to use because their creators aim to make a profit, so they need to sell them. Among them:

1. Screaming Frog SEO Spider – one of the best web scraping programs from developers in England; multifunctional and intuitive, it is deservedly popular; costs about £150 per year (around $200); you can try a limited-functionality trial version suitable for working with 500 links;
2. NetpeakSpider – another excellent option, priced at $15 per month for the most convenient version, with a free version also available;
3. Comparador – a simple and clear site parser that also checks site indexability in search engines;
4. ExtractEmails.ru – scrapes data from bulletin boards and directories, collecting phone numbers and email addresses.

Browser Extension Web Scraping Software

Disadvantages include lower scraping efficiency and weaker functionality; advantages include mobility and simplicity. Here we can mention:

1. Scraper – a scraping extension for Chrome;
2. Outwit Hub – works with Mozilla Firefox, offers broader functionality;
3. 80legs – used for analyzing large data sets, works with PayPal.

Custom Web Scraping Software

As mentioned, such a scraping solution requires time and knowledge of programming languages. To write a program in Python, you can use the BeautifulSoup module and the Selenium library, which is needed to load the HTML version of the site. Instructions for writing scraping software are easy to find online.

Contact Data Analysis

Often, web scraping targets various contact data such as mobile phone numbers, email addresses, and URLs. This data might be collected, for example, to notify visitors of your own site, for advertising mailings, or to carry out fraudulent operations.

In this case, LetsExtractEmailStudio is an excellent choice. The program is tailored for collecting and analyzing contact data, has the appropriate functionality, and is easy to use. It comes in a demo version; the full version costs $80.

Even in the demo version, you can start full-fledged web scraping. To do so, activate the New Search button, enter the site, find the desired page in the browser that appears, and click Extract Members. Then, you may need to enter account information because many platforms (Facebook, VKontakte, etc.) restrict capabilities for unregistered users. After that, you will see the main screen displaying email addresses and other related data. The full version allows you to verify email validity. Click New Search, then Extract Email, select the file with emails, and click Email Verify.

Obstacles to Web Scraping

It is possible to successfully counter scraping programs. The main methods are:

1. Restrict access rights – close access to the site for everyone except administrators;
2. Block bots – most sites are designed to be noticed and appear in search results by Google and Yandex bots, but you can also close the site to them;
3. Block by IP – as mentioned, with a high number of requests, you may be banned from a particular site;
4. CAPTCHA – well-known verification (image sets, letters, etc.) to determine whether the requester is a human or a bot; although there are systems that simulate human page views;
5. Blacklists – you can find IP addresses from online databases and add them to your own blacklist to block them from your site;
6. DDoS protection programs – designed to prevent overloads by filtering bots, can also help in the case of web scraping.

What Does the Law Say About Web Scraping?

Russian legislation allows the collection of data from open sources, including websites, but prohibits:

1. “Bringing down” sites with scraping that constitutes DDoS attacks;
2. Obtaining data that constitutes personal or commercial secrets;
3. Publishing data obtained via scraping that is protected by copyright.

Business of Web Scraping

Web scraping is associated with a huge number of offers online. For money, people offer to copy product cards from websites, competitor site designs, etc. Knowing how to use the appropriate scraping software, you can indeed make money from it.