What are some good resources for learning the internal components of Rails codebase?

Question

I have been developing in Rails for about 3 years and would like to know more about Rails itself. Rails 3 supposedly provides a good API for working more closely with Rails, but it's hard for me to find documentation on how to use them. Here are some examples of what I'm looking for:

Rails Initialization Process http://guides.rubyonrails.org/initialization.html

Arel Walkthrough http://railscasts.com/episodes/239-activerecord-relation-walkthrough

Routing Walkthrough http://railscasts.com/episodes/231-routing-walkthrough http://railscasts.com/episodes/232-routing-walkthrough-part-2

Rails Craft Applications http://pragprog.com/book/jvrails/crafting-rails-applications

Are there any other good resources that help as a guide to working with Rails? (and please don’t say read the source code. I am looking for a more detailed explanation)

Answer 1

There are some chapters in the Ruby Metaprogramming Book at the end of which describes how the internal elements of ActiveRecord are created.

Answer 2

You may like the following articles:

http://piotrsarnacki.com/2010/07/31/rails3-modularity/

http://piotrsarnacki.com/2010/06/18/rails-internals-railties/

But you should start writing such articles yourself, i.e. try to write how the controller instance variables are visible in the views or prepare a description of all modules and classes of rails - this will make you much more family with rails.