Agile Web Development With Rails: A Pragmatic Guide (The Facets of Ruby Series) [ペーパーバック]

Ruby on Rails is a pretty young technology. Its first release was midway 2004, and it has been gathering momentum since late 2004. It has yet to see its official 1.0 release. So it is a pleasant surprise that there already is a book available (electronically since June 2005), and that it such a good book!

Why read this book? Since Dave Thomas' credentials as a technical writer are well established (pick up The Pragmatic Programmer if you haven't got it already), this question boils down to: why learn more about Ruby on Rails?

For me, the answer was that I have long been looking for a simpler way to build web-applications. I'm a J2EE developer, and it seemed that every project I joined had a different set of frameworks. All of those frameworks could be configured to work together, and there are even frameworks whose only purpose is to make other frameworks work together. There are tools that generate stubs to wrap frameworks, and frameworks that wrap other frameworks, so that the developer needs not know what the underlying framework is.

Madness.

Rails behaves as if it were one framework. Configuration is simple (no xml) if you need it at all, since the defaults are pretty smart. Writing tests for your model and your controllers is actually easy. The API documentation is very good. Instead of mucking around with frameworks, you find yourself thinking: What do you want to do today?

Drawbacks: Is Ruby on Rails slow? Performance is acceptable, I think, especially considering that web applications are database-bound. Rails also scales well - and anyway, processors are cheap, brains are not.

Is Rails proven technology? Clearly it's not, it's the new kid on the block. More seriously, Rails is still in flux - the core api is still changing, and it could still take some time to settle down. So now is not the time to start huge Rails projects, now is the time to learn rails and build prototypes and small projects.

And with that, this book will be a tremendous help.

This book was in development through July 2005 and provides a timely introduction to the excellent web framework Ruby on Rails. Rails is a full stack, open-source framework in Ruby (see rubyonrails.com). I can think of no better way of learning Rails than buying this book (and Programming Ruby, "Pickaxe 2", if you are a Ruby newbie) and working through the hands-on bookstore building exercise in a weekend. "Agile" development takes center stage, as you might imagine from the title. Because of the dynamic nature of Ruby and the way Rails extends the core language, Ruby on Rails lets you easily modify, run, and test web apps.

The first part of the book (Chapters 4 to 12) shows how to develop a bookstore app in an iterative fashion. A mock client asks for improvements and the authors show how you build a web app that meets the client's needs. A number of best practices have been distilled from other languages/platforms, and you'll see how they come together coherently in Rails. The Model-View-Controller (MVC) pattern for separating data, presentation, and business logic. Integrated testing. Ways to not repeat yourself across code and configuration files. Active Record pattern for handling data sources. In addition to what's taken from other platforms, the Rails developers extensively use the metaprogramming features of Ruby to wrap these best practice ideas in a nice domain specific language, and this book gives you a good overview of the Rails web app language. "Convention over configuration" is another key to Rails development, and a number of figures show the Rails convention in directory layout, naming, and URL mapping.

Although the book is very accessible to Ruby newbies (in part due to an appendix that provides a quick intro to the language), it assumes some knowledge of core Web technologies. You should be acquainted with HTML and databases (like MySQL). The sweet spot for this book might be PHP, Java, and .NET web programmers. The third part of the book drills down into Rails. You'll learn all about the Active Record object-relational mapping layer, and how easily you can specify relationships, validations, and structures like lists and trees. Other chapters focus on the controller and view portions of the MVC approach. The integrated "AJAX" (asynchronous javascript) support gets a chapter, as do e-mail (Action Mailer) and web service support. The book concludes with a couple of chapters on security and the best ways to deploy and scale your web app.

This book was written in an agile fashion; I can't remember another computer book that was in print a single month after editing was finished. Despite the speed of publishing, the book can't hope to cover all the new developments given the momentum of Rails. What won't be in the book but might be useful to Rails programmers? SwitchTower is a new utility to automate application deployment (among other things), and ActionStep will be a Rails-friendly framework for writing rich GUIs that target the client-side Flash player. But if you want to learn what Tim O'Reilly said might be the "perl of Web 2.0", you should start with "Agile Web Development with Rails" and supplement it liberally with readings off the web.

Highly recommended book. Although this is the first of more than a half-dozen Rails books, it'll be hard to compete with the authors of this book: Dave Thomas, who wrote the preeminent Ruby textbook, and David Heinemeier Hansson, who was the brains behind Rails.

Rails, or more appropriately Ruby on Rails is the new web application development framework that everyone is so excited of and raving about how it cuts development time by a factor of 10 and does away with the cumbersome XML configuration files that are the hallmark of J2EE.

Being an old Java hand, I wanted to see firsthand if there was some substance beneath all the hype. I was also intrigued by the fact that many other old Java hands whom I respect and admire, like James Duncan Davidson, Elliotte Rusty Harold, Bruce Tate, Graham Glass, and Brian McAllister are now fervent (to different degrees) rubyists and Rails-enthusiasts. If it weren't for them, I would never have undertaken this journey, probably.

But anyway, this is supposed to be a book review, not a chronicle of my ongoing discovery of Rails.

I mostly like using books to discover and learn about new technologies, so it's perfectly natural that I decided to take off with what is considered the book about Rails. And how could it be not, with Rails' creator David Heinemeier Hansson as one of its authors?

It is also the only one published so far but, even though the choice was a bit, uhm ... limited, I wasn't disappointed. The book, as is customary with titles from The Pragmatic Programmers' bookshelf, is very good. It lays down in detail almost everything you need to know to be productive with Rails, save for the language Ruby itself. To be honest, the book includes an appendix introducing the basics of Ruby, but it's just the bare minimum. I suggest getting yourself a good Ruby book (like Programming Ruby, also from The Pragmatic Programmers, which I am currently reading and will review shortly) if you really want to get the most out of Rails.

Another caveat you have to be aware of is that Rails is a quickly moving target. The book covers version 0.13, which was current around mid-2005. There was a 0.14 version after that and we are now at 1.0, since a few weeks ago. However, I didn't find I had much to change while experimenting with Rails following the book. As always with Open Source software, resorting to the mailing lists, forums or the #rubyonrails@freenode.net IRC channel is the best avenue for finding answers to your doubts and asking support questions.

The book is organized in four parts:

Part I introduces the design principles behind Rails, its most important concepts and briefly covers how to get started by installing it and writing your first program. The part about installation is the one that is bound to become quickly obsolete, as new and easier installation methods for the various supported platforms are developed.

Part II dives into Rails by guiding you along the development of a real (albeit much simplified) e-commerce application. I find this approach to be very good and "pragmatic" indeed. Of notable interest is the chapter on testing. It's great to see that providing a good test scaffolding was one of the main design concerns in Rails and not just an afterthought.

Part III goes deeper into Rails and can be used as a reference for its components, like Active Record, Action Controller, and Action View. Bonus chapters on AJAX, Web Services, security, deployment and scaling issues are included here and will make the book even more valuable when you need to deal with "real world" applications.

Part IV contains the appendices, like the above mentioned introduction to Ruby, a reference of configuration parameters (be warned again: these might change), the full source code for all samples (of dubious value, in my opinion), and a list of online resources (once again, a list bound to be more and more incomplete as time passes and the excitement around Rails grows).

Overall, I find the quality of this book to be excellent. It's not thick to the point of being too heavy to carry around in your laptop bag, for those times when you need to peek at it, yet it covers enough of Rails to be considered a complete and authoritative reference. This is probably a testament to Rails' simplicity too.

The writing style is eminently readable. You can read it cover to cover, if you like, without getting bored. The frequent sidebars make it lively without being too distracting. A great amount of care and craftsmanship went into producing this book, and it shows.

Highly recommended!