Flex and Ruby on Rails Integration
Integration between Flex and Ruby on Rails is becoming more common as open-source Flex projects enable developers to easily create Flex applications that work well with RoR. Flex is widely known as a tool which makes the job of developing Rich Internet Applications easier than before. Additionally, Ruby on Rails has simplified the process of creating database-driven web applications. The integration of Flex with RoR applications is helping developers create advanced, rich and powerful web applications with less effort and more success. The following are 7 examples of successful Flex and RoR integration:

Ruby on Rails RIA SDK for Flex
Adobe has provided an open source SDK on Google code which provides developers with samples and code to help develop solutions with Ruby and Adobe technologies. The SDK assists with the integration of Flex with RoR and contains open source code created by third parties as well as samples and demos that have been created by project members.
URL: code.google.com/p/rubyonrails-ria-sdk-by-adobe/

RESTFul Rails from Flex
REST (Representational State Transfer) is a term coined by Roy Fielding to describe a style of software architecture for distributed hypermedia systems such as the World Wide Web. REST strictly refers to a collection of network architecture principles which outline how resources are defined and addressed.  RESTFul Rails from Flex is a part of the “MySpyder” project by Daniel Wanja. His work enables a Flex front-end to access a RESTFul Ruby on Rails service.  The RESTFul approach to RoR allows the exposure and manipulation of a Rails model via a predefined set of standard http requests.
URL: onrails.org/articles/2007/02/10/restful-rails-from-flex

Flexible Rails
The eBook Flexible Rails and its sequel Enterprise Flexible Rails teach about using Adobe Flex 3 and Ruby on Rails 2 together to build Rich Internet Applications (RIAs).  Flexible Rails shows coders how to progress from simpler methods of integration to advanced ones while using the same application.  The step-by-step instruction is extremely useful because the author supports different environments and gives options for different platforms, making the book applicable to everyone.  A more in-depth review of these books is to come.
URL: www.flexiblerails.com

Ruby on Rails 1.1 and Flex 2.0
Liverail.net provides a good two-part tutorial by Stuart Eccles at liverail.com explaining the integration of Ruby on Rails and Flex. The step-by-step tutorial is very helpful for advanced developers of these technologies. According to Eccles, “Flex can consume and publish to XML-based URL services to create dynamic applications with a rich client. Rails 1.1 has some great REST features which make it a truly rapid development backend for Flex applications.”
URL: www.liverail.net/articles/2006/4/16/rubyonrails-1-1-and-flex-2-0-pt-1

Combining the Power of Flex 2 and Ruby on Rails
Nicolas Fonrose of Valtec presents a good, easy to understand presentation about the power of combining Flex 2 and Ruby on Rails into a perfect couple. The presentation covers very important and core areas like “Why Combine Flex and RoR,” “Changing the Presentation Layer,” “Building an RoR Service,” and “Creating the Application.”  This website provides great insight for beginners.
URL: www.valtech-tv.com/permalink/2345/combining-the-power-of-flex-2-and-ruby-on-rails-part-i.aspx

Integrating Flex 2 and Ruby on Rails
An article by Derek Wischusen of flexonrails.net teaches how to integrate Flex 2 with Ruby on Rails and a MySQL database by building a simple issue tracker application. The article also identifies practices to add functionality to the application, such as adding a new bug to the database, reading existing bugs, updating a bug, and deleting a bug. In his article, Wischusen says, “When using Flex, you have several options to choose from for back-end server software. So why might you want to choose Rails? Ruby on Rails, like Flex, is a well thought out, elegantly simple framework. As you will see, Rails uses code generation and metaprogramming to make it incredibly easy to integrate with a database using almost no SQL code. Furthermore, when you use Rails, you also get to use Ruby, a programming language that is both extremely powerful and easy to use. Using Flex and Ruby on Rails, you will be able to get more done with less code.
Flex + Rails + Ruby = RIA Nirvana.”
URL: www.adobe.com/devnet/flex/articles/flex2_rails.html

Cairngorm-Rails-Generator
Cairngorm is a framework for more complex Flex-based RIAs. An open source Flex / Cairngorm generator for Ruby on Rails by Ilya Devers is available for Google code. The project hosts a number of rails generators for the Cairngorm mvc micropattern and Ruby on Rails and Flex SDK.
URL: code.google.com/p/cairngorm-rails-generator/


Conclusion
Integrating Flex and Ruby on Rails produces great products utilizing the front end capabilities of Flex and the database strength of RoR. Also, both frameworks are very powerful as well as easy to incorporate and exercise. Due to these facts, more and more developers are being attracted toward the outcomes of integrating these two technologies.


References
Mike Potter (2008). An Update on Flex and Ruby on Rails Integration. Retrieved Dec. 23rd, 2008 from blogs.adobe.com/mikepotter/2007/01/an_update_on_fl.html
Luciano Ramalho (2008). Flex and Rails Integration on Many Fronts. Retrieved Dec. 23rd, 2008 from www.infoq.com/news/2007/01/flex-rails