For data owners, How to prevent web scraping? For Scrapers, How to scrape efficiently? Read this guide to get the best solution.
Every time you input a search query on Google, the bots are at work – scouring the internet for information on that query. But how do these bots retrieve information within seconds? It is a technology known as “web scraping“.
Google and other search engines use bots to scrape sites on the web and rank content accordingly for their users. Web scraping allows analyzing a large volume of data that would be impossible for humans to process in such a quick manner.
For instance, traffic apps leverage bots to gather information on the internet and bring the gather data under one roof for their user's convenience.
But the big question is,
“Is it legal to scrape a website?”
Over the years, several tutorials have emerged online, espousing the concept of web scraping. But what is somewhat troubling is the widespread ignorance about its legality.
The answer to this question – it depends,
How Websites Use Terms and Conditions to Protect Their Content
Do web scrapers target your website?
If yes, there is a way you can hold your ground or at least stand a good chance of winning the war and blocking such activity on your site.
Firstly, you can indicate to be explicit in your terms and conditions, thereby prohibiting third parties from scraping your content for commercial purposes.
For adequate protection, the terms and conditions must be enforceable— they become enforceable when both parties agree to it. However, the court may go through another route — use different criteria in establishing if such an agreement exists.
Most website owners go for a “clickwrap” agreement rather than a “browsewrap.” With a “clickwrap,” the user will have to indicate agreement before they can access any information on the site. On the other hand, a “browsewrap” only notifies that using the website means you agree to its terms.
By implementing a “clickwrap” agreement, you’ll present a stronger case that requires visitors to indicate agreement before they get access to any available information on your site.
Anti-scraping Measures for Data Protection
Hold your Legal Stand
One of the best ways to prevent scraping is to state it categorically on your Terms of Service that web scraping is not allowed. You can sue any scrapers if they do choose to ignore your stated terms. Take, for example, LinkedIn suing scrapers, and considering them to be hackers since they extracted users' data via automated requests.
Avoid Denial of Service (DoS) Attacks
Putting up a legal notice that prohibits scrapers from accessing your information may not cut it, as attackers may still want to accomplish their act. This could result in a denial of service due to an enormous number of requests traveling to the website. Consequently, your website’s server can shut down if it can’t handle it.
However, by filtering incoming requests through a firewall, you can identify potential attackers’ IP addresses and subsequently block their requests.
Blacklist or Whitelist Specific IP Addresses
You can block an IP address that is used for scraping data from your website. By identifying the pattern of the IP addresses or IP address, you can initiate the action through the .htaccess file, or even whitelist some other IPs to allow requests from them
How to Outsmart Web Servers Implementing Anti-scraping Measures
Even with legal actions stated, internet users, will always find a way around any snag to achieve their goal. Especially for those who do scrapping legally (even though some people still believe there are no words like “doing web scraping legally”). In that light, there are various ways to counter any anti-scraping measures put in place by website owners.
Scraping Speed is Important
Fetching data with your scrapper as quickly as possible can get you exposed, as no human can surf the web at such a pace. The website may monitor your access speed, and if they realize you’re flipping through pages too fast, issue you a block. When writing the script include “sleep” in the code or better yet, set up wait time when building your crawler.
When a site detects several requests coming from a single IP address, they may place restrictions. To avoid sending all of your applications through the same IP address, you can use proxies or a web scraping API.
The use of proxy servers may suffice here to avoid sending requests from a single IP address. However, if you use a single proxy server, rest assured you will encounter the same problem. So, individuals that are into web scraping harness a vast amount of proxies and rotate them to slip under web servers radars, you can learn more from here.
Be Careful of Honeypot Traps
Honey pots are links which the regular visitor cannot see but are present in the HTML code, and web scrapers can locate them. They act like traps to send scrapers to blank pages. As soon as you are redirected to a blank page, the website immediately identifies that it is a crawler and block request from that client altogether. Never visit the same page and ensure that you use different parameters, so it looks like a human being is surfing the desired data source.
Some stakeholders have continued to search endlessly for answers to “Is it legal to scrape a website?” Some believe that web scraping is illegal; bots steal information and use it to the advantage of the owner — making a profit in the process at the expense of the website owner.
On the other side of the divide, gathering publicly available information is legal. Otherwise, Google would have long be gone as an entity — because they are the biggest scrapers on the web. They are taking data from every known website in the world. If Google is doing it, where is the illegality here?
When you crawl websites for data, have these in mind:
- Go by the Terms of Service (ToS) of the site.
- Stick to the rules of robots.txt.
- Never bombard with several requests — a reasonable crawl rate will suffice.
- Use a legitimate user agent string to identify your web scraper.
- Ask for written permission if TOS or robots.txt prevents you from scraping.
Or if you would like to outsource a web data gathering tool, Crawlera offers a robust and most advanced Real-Time Crawler solution on the market as of yet. If you do outsource data gathering tools, you can forget about legal stuff and concentrate on the data you extract to gain actionable insights.
The problem usually occurs when you scrape people’s websites without prior permission. Or you ’don’t follow stated terms of conditions that prohibit such activity. If you do so, you’re getting yourself in a vulnerable position.
Simply, crawl or scrape websites under the ambit of the law — like RESPECTING their Terms of Service (TOS). Otherwise, the owner can pursue legal action against you.