Technologies and platforms used

We use a number of technologies in this chapter, mainly revolving around the Ruby programming language and its various libraries. In addition to Ruby and its libraries we also use a few mashups, which are described below. For more information on the technology stack used in this book (and in this chapter) please refer to Chapter 1.

Mashups

As with previous chapters, while the main features in the applications are all implemented within the chapters itself, sometimes we still depend on other services provided by other providers. In this chapter we use three services—RPX for user web authentication, Gravatar for avatar services, Amazon S3 for photo storage, and Pixlr for photo editing.

RPX

RPX is an authentication provisioning service provided by JanRain, a technology startup with deep roots in the OpenID community. It doesn't do the actual authentication itself but acts as a proxy to a multitude of third party authentication providers such as Google, Yahoo!, MySpace...