Review By: Lorne Schachter
09/01/2011There's no doubt about the pervasiveness of the web today. You can do almost everything you need to do on the web, and relatively simply at that. Fill in a form, click a button, and, before you know it, you've bought or updated something. What could be easier? In fact, the nature of web interaction is becoming a paradigm for service interactions. How it works and how can we leverage and extend it is what REST in Practice is all about.

REST stands for "representational state transfer." The web is a distributed application whose resources communicate by exchanging state information. The web works through HTTP and its variants (e.g., HTTPS). These protocols provide us operations that we use to perform services—typically POSTs and GETs—and statuses indicating the outcome of the service requests. On a simple level, that's all there is to it. Only, life isn't that simple and this explanation raises more questions than it answers. When web services are done well, there is, according to the authors of this book, a flow to the interactions. The key to implementing web services effectively is to understand this flow.

The leading use for web services these days is in commercial applications. The authors begin with a business as it makes its initial migration to the web. They then explain how the service model changes and expands as the business grows and provides more and more services over the web. You can see how the business evolves in a very natural, understandable way. You may find yourself saying, "Oh, right. That's obvious," except that it's wasn't obvious before you read it, and that's the beauty of the presentation. The authors take a topic that is complex in implementation and give a clear exposition that makes it almost intuitive.

I think the primary audience for REST in Practice is experienced programmers who don't necessarily have a lot of experience developing the latest web applications. They'll understand the basics of the problem and really benefit from the nuances of the authors' explanation. Others will certainly benefit from the book, but at least a rudimentary understanding of how the web works will make the reader’s life a lot easier. The current growth of web services and commercial applications means that the book will have a long shelf life, with the information only growing in relevance.