cache.rb

require "rack/cache"

if Rails::VERSION::MAJOR == 2
  Rails.configuration.middleware.use Rack::Cache, 
    :metastore   => "file:#{Rails.root + "cache/rack/meta"}",
    :entitystore => "file:#{Rails.root + "cache/rack/body"}",
    :verbose     => true
else
  module Cache
    class Railtie < Rails::Railtie
      railtie_name :rails_cache

      initializer "rails_cache.insert_rack_cache" do |app|
        app.config.middleware.use Rack::Cache,
          :metastore   => "file:#{Rails.root + "cache/rack/meta"}",
          :entitystore => "file:#{Rails.root + "cache/rack/body"}",
          :verbose     => true
      end
    end
  end
end

cache2.rb

require "rack/cache"

Rails.configuration.middleware.use Rack::Cache, 
  :metastore   => "file:#{Rails.root + "cache/rack/meta"}",
  :entitystore => "file:#{Rails.root + "cache/rack/body"}",
  :verbose     => true

cache3.rb

require "rack/cache"

module Cache
  class Railtie < Rails::Railtie
    railtie_name :rails_cache

    initializer "rails_cache.insert_rack_cache" do |app|
      app.config.middleware.use Rack::Cache,
        :metastore   => "file:#{Rails.root + "cache/rack/meta"}",
        :entitystore => "file:#{Rails.root + "cache/rack/body"}",
        :verbose     => true
    end
  end
end

env.rb

RAILS_GEM_VERSION = '2.3.5' unless defined? RAILS_GEM_VERSION
require File.join(File.dirname(__FILE__), 'boot')

Rails::Initializer.run do |config|
  config.gem "rails-cache", :lib => "rails/cache"
end

Gemfile

gem "rails-cache", :require => "rails/cache", :path => "../rails-cache"

Rakefile

require "rake"

begin
  require "jeweler"
  Jeweler::Tasks.new do |gem|
    gem.name = "rails-cache"
    gem.summary = "Add Rack::Cache to your Rails app"
    gem.email = "nicolas.merouze@gmail.com"
    gem.homepage = "http://github.com/nmerouze/rails-cache"
    gem.authors = ["Nicolas Mérouze"]
    gem.files = Dir["*", "{lib}/**/*"]
    gem.add_dependency("rack-cache", "~> 0.5.2")
  end
  
  Jeweler::GemcutterTasks.new
rescue LoadError
  puts "Jeweler (or a dependency) not available. Install it with: sudo gem install jeweler"
end