Carlo Pecchia

Ruby on Rails 2.2 - some news (part 1)

The release candidate 2 of Rails 2.2 has been just announced. Let’s see some of the most interesting (IMHO) news.

Documentation

Personally I often use gem server to browse through classes documentation, but sometimes a more homogeneous “guide” could help a lot.

A new Rake task is added:

$ rake doc:guides

it generates the new Rails guides under doc/guides. These, still a work in progress, cover all the (basic) aspects of the framework:

• Getting started with Rails
• Rails Database migrations
• ActiveRecord associations
• Layouts and rendering with Rails
• ActionView form helpers
• Rails routing from the outside in
• Basics of ActionController
• Rails caching
• Testing Rails applications
• Securings Rails applications
• Debugging Rails applications
• Benchmarking and profiling Rails applications
• The basics of creating Rails plugins

More, the graphical appearence is (very) nice:

Multithreading

Now Rails is thread-safe (especially in waiting for Ruby 1.9 release), obviously “the whole thing” depends on sever infrastructure you deploy it.

Anyway it is now possible to enable multithreading dispatching simply putting:

config.threadsafe!

in config/environments/production.rb file.

ActiveRecord

The facility of connection pooling is introduced for database requests: a restricted set of database connections reused among different requests. To enable it insert the following configuration directives in config/databases.yml:

development:
  ...
  pool: 10
  wait_timeout: 5

More, the new method ActiveRecord::Base.connection_pool allows direct access to the pool.

Now it is possible to spcify joins conditions using an hash:

class Post < ActiveRecord::Base
  has_many :comments
end

class Comment < ActiveRecord::Base
  belongs_to :post
end

Post.find(:all, :joins => :comments, :conditions => {:comments => {:approved => true}})

Conclusion

Obviously a lot of other work has been done, you can read more about it on official announcements.