The success of a data collection exercise is contingent on a few factors. Firstly, it is important to understand the legal and ethical limits that define what you can or cannot collect. Second, it is equally crucial to establish if there are geographical restrictions (geo-blocking) that could prevent you from collecting the data you had initially planned to extract. Thirdly, and perhaps most importantly, it is vital to consider that nowadays, websites integrate anti-scraping techniques aimed at thwarting any web scraping methods. That said, the good news is that you can go around these problems by implementing some proven web scraping best practices that we have explored in this article.
Web scraping generally defines the automated process of extracting publicly available data from websites. It is mainly carried out by bots or software known as web scrapers. You can either purchase off-the-shelf scrapers or create a scraping bot using Python’s web scraping libraries, such as the Python requests library.
Benefits of Web Scraping
Also known as web data extraction or web data harvesting, web scraping can greatly benefit businesses, investors, and individuals. For instance, by collecting review data and feedback posted on review sites and e-commerce platforms, companies can establish the level of customer satisfaction as well as what they like or dislike about a product or service. And based on this information, the companies can either introduce new products or improve their existing offerings. Other benefits that businesses can realize by scraping data from websites include:
- Reputation monitoring
- Competitor monitoring/market research
- Price and product monitoring
- Lead generation
- Search engine optimization (SEO)
- Background checks on suppliers and partner organizations
Similarly, web scraping enables investors to retrieve important data about markets or companies they intend to invest in or acquire. With this background information, they can make informed decisions. For individuals, web scraping also comes in handy when they intend to scalp products.
That said, these benefits can only be realized when businesses, investors, or you as an individual implement some of the web scraping best practices.
Web Scraping Best Practices
The best routines for web scraping lie in combining technologies and solutions. As stated above, websites are increasingly implementing anti-scraping techniques, which include:
- CAPTCHA puzzles
- IP blocking
- Sign-in and login requirements
- Header requirements and User Agents
- AJAX/dynamically updating content
- Honeypot traps
Bypassing these anti-scraping techniques, especially given how technology has evolved in 2022, requires a concerted effort that involves technology-based solutions as well as behavioral-based interventions. So, what are the best routines for web scraping?
The web scraping best practices include:
- Mimicking human browsing behavior
This behavior-based intervention is aimed at slowing down the rate of web scraping to a speed that mirrors how a human being would browse a website. This way, you will avoid detection, especially keeping in mind that web scrapers can browse and click through web pages at speeds that human beings cannot logically achieve. If you do not mimic human browsing behavior, there are high chances that your IP address could be blocked as the speed would constitute unusual traffic/activity.
- Using proxies
A proxy is a computer that routes all requests through itself before directing them to the target web server. The proxy hides the requests’ original IP address, which identifies your computer’s real IP address, and assigns them a new online identifier. In doing so, the proxy anonymizes the outgoing requests, protecting your actual IP address from detection or blacklisting should the web server detect unusual activity.
- IP rotation
In tandem with using proxies, it is also crucial to use rotating proxy servers. This type of proxy regularly changes the assigned IP address. This way, they minimize the number of requests originating from a single online identifier, and this goes a long way to ensure the web scraper mimics human browsing behavior.
- Rotating User Agents and request headers
User Agents (UA) and request headers contain information that identifies, among other things, the computer’s operating system and version, browser, and browser rendering engine. On the other hand, a header defines the origin and nature of an HTTP request. Rotating both the UA and request header makes it appear that the web scraping requests are sent by multiple users rather than the same computer. And if you are creating a custom web scraper using Python, you can customize your HTTP requests’ headers using the Python requests library – read this comprehensive article for more details.
- Headless browsers
- Adherence to the robots.txt file
The robots.txt file contains instructions that stipulate the web pages within the websites that a bot can access as well as those that are a no-go-zone. Adherence to these instructions prevents IP blocking.
It is important to follow some proven practices to successfully undertake a web scraping exercise and experience its benefits. The best routines for web scraping include both technology-based solutions and behavior-based interventions.