The challenges in crawling the Web.
At PromptCloud, Data as a Service (DaaS) is our operating model. We scrape and crawl the Internet to bring our clients the data they require. Operating in this niche field isn't without its challenges.
We find that as an evolving field, extracting data from the web is still a gray area. Why?
Because there are no clear ground rules regarding the legality of web scraping.
Moreover, people and organizations are increasingly growing wary about how data is or can be used. Already, Big Data is being frowned upon; its harvesting, even more so. Add to it the large investments required and it just makes Big Data even less attractive and appealing to SMEs and generally regarded as the domain of large enterprises.
Yet, undeniably, data crawling is growing exponentially. And as it grows, the Web is gradually becoming more complicated to crawl. How?
Challenge I: Non-Uniform Structures
Data formats and structures are inconsistent in the ever-evolving Web space. Also, norms on how to build an Internet presence are non-existent.
Lack of uniformity and the vast ever-changing terrains of the Internet.
Collecting data in a machine-readable format becomes difficult. Also, problems increase with increase in scale.
a) structured data is needed, and,
b) large number of details are to be extracted w.r.t. specific schema from multiple sources.
Challenge II: Omnipresence of AJAX elements
AJAX and interactive web components make websites more user-friendly. But not for crawlers!
Content is produced dynamically (and on-the-go) by the browser and therefore not visible to crawlers.
To keep the content up-to-date, the crawler needs to be maintained manually on a regular basis. So much so, that even Google’s crawlers find it difficult to extract information!
Crawlers need to be refined in their approach to be more efficient and scalable. We have a solution that makes crawling AJAX pages prompt. Click here.
Challenge III: The “Real” Real-Time Latency
Acquiring data-sets in real-time is a huge problem! Real-time data is critical in security and intelligence to predict, report, and enable preemptive actions against untoward incidents.
While near-real-time is achieved, real-time latency remains the Holy Grail.
The real problem comes in deciding what is and isn't important in real time.
Challenge IV: Who owns UGC?
Only 2-3 % sites disallow bots. Others believe in data democratization, but it is possible these may follow suit and shut access to the data gold mine!
Site policing for web scraping and rejecting bots.
Challenge V: The Rise of Anti-Scraping Tools
Restriction on web crawlers via e-mail obfuscation, real-time monitoring, and instant alerts etc.
This is <1%, yet it may rise; all thanks to rogue crawlers! These crawlers disregard robots.txt files and are responsible for multiple hits on target servers. Eventually effecting DDoS to too many sites!
Despite these challenges, web data is a vast uncharted territory full of bounty. Of course, having the proper tools helps and so does knowing how to use them. On retrospect, there exists a very thin line between being ‘crawlers’ and ‘hackers’; and this is where the genuine concern for privacy arises.
At PromptCloud, these crawling challenges are met head-on. Our two ground rules we recommend that every web-crawling solution should follow.
Courtesy: In our experience, a little courtesy goes a long way. Burdening small servers and causing DDoS on target sites is easy. Yet it is detrimental to the success of any company – especially small businesses!
As Rule #1, we allow at least an interval of 2 seconds in successive requests thereby avoiding hitting servers too hard.
Crawlability: Many (and most) websites restrict the amount of data (either sections of the site or complete sites) that can be crawled by spiders via the robots.txt file.
Rule #2 is to establish feasibility of such site(s)!
It helps greatly to check the site’s policy on bots — whether it allows bots in target sections from where data is desired.
While there are many other safe crawling and extraction methods, the aforementioned are our favorites. And while the Web may be rife with challenges, overcoming them by following simple steps is easy!
Thank you for reading!