Sam Ruby - Agile Web Development with Rails 4

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Rails is constantly evolving and, as it does, so has this book. Parts of the Depot application were rewritten several times, and all of the narrative was updated. The avoidance of features as they become deprecated have repeatedly changed the structure of the book as what was once hot became just lukewarm.

So, this book would not exist without a massive amount of help from the Ruby and Rails communities. To start with, we had a number of incredibly helpful formal reviewers of drafts of this book.

Additionally, each edition of this book has been released as a beta book: early versions were posted as PDFs, and people made comments online. And comment they did; over time more than 1,000 suggestions and bug reports were posted. The vast majority ended up being incorporated, making this book immeasurably more useful than it would have been. While thanks go out to all for supporting the beta book program and for contributing so much valuable feedback, a number of contributors went well beyond the call of duty.

Finally, the Rails core team has been incredibly helpful, answering questions, checking out code fragments, and fixing bugseven to the point where part of the release process includes verifying that new releases of Rails dont break the examples provided in this book. A big thank you to the following:

Ruby on Rails is a framework that makes it easier to develop, deploy, and maintain web applications. During the months that followed its initial release, Rails went from being an unknown toy to being a worldwide phenomenon; more important, it has become the framework of choice for the implementation of a wide range of so-called Web 2.0 applications.

Why is that?

A large number of developers were frustrated with the technologies they were using to create web applications. It didnt seem to matter whether they used Java, PHP, or .NETthere was a growing sense that their jobs were just too damn hard. And then, suddenly, along came Rails, and Rails was easier.

But easy on its own doesnt cut it. Were talking about professional developers writing real-world websites. They wanted to feel that the applications they were developing would stand the test of timethat they were designed and implemented using modern, professional techniques. So, these developers dug into Rails and discovered it wasnt just a tool for hacking out sites.

For example, all Rails applications are implemented using the Model-View-Controller (MVC) architecture. Java developers are used to frameworks such as Tapestry and Struts, which are based on MVC. But Rails takes MVC further: when you develop in Rails, you start with a working application, theres a place for each piece of code, and all the pieces of your application interact in a standard way.

Professional programmers write tests. And again, Rails delivers. All Rails applications have testing support baked right in. As you add functionality to the code, Rails automatically creates test stubs for that functionality. The framework makes it easy to test applications, and as a result, Rails applications tend to get tested.