Building a Web Spider with Ruby

Spider on the Web


Ruby is a very elegant language,and it’s harmonious – the parts work together effectively. Ruby also significantly reduces a developer’s burden. We’ll show you how to use Ruby to build a quick and simple web spider application.

Ruby is a scripting language developed by Yukihiro Matsumoto and released under the GPL. The Ruby language has an excellent set of string manipulation and networking libraries, making it a great choice for writing web spiders. If you are not familiar with web spiders, they are programs designed to automatically traverse the web. Search engines use web spiders to add web pages to their index; companies like Netcraft use spiders to get statistics on web servers. You can use a web spider to find information automatically from almost any website; in this article, we’ll discuss how to use Ruby to retrieve information from LiveJournal, a popular weblog provider. You can extend these techniques to virtually every website that provides public information.