ugly hack for caching out merged assets for heroku deploy

deploy.rake

require 'jsmin'
require 'aws/s3'
require 'yui/compressor'

task :deploy => ['deploy:console']

namespace :deploy do
  task :console => :environment do
    if Rails.env != 'production'
      puts "We need to be running in production environment, ie 'rake RAILS_ENV=production deploy'"
      exit 0
    end
    puts "\n\033[0;31mMake sure you don't have any staged Git commits before deploying\033[0m"
    avilable_environments = `git remote`
    puts "\nPlease select environment for deploy (should be one of #{avilable_environments.split("\n").join(', ')})"
    print ": "
    environment = STDIN.gets.chomp
    if !avilable_environments.include?(environment)
      puts "Unknown environment"
      exit 0
    end
    
    puts 'Caching assets ..'
    Rake::Task['deploy:cache_assets'].invoke
    Rake::Task['deploy:commit_cached_assets'].invoke
    
    puts 'Deploying site to Heroku ...'
    puts `git push -f #{environment} master`
    
    Rake::Task['deploy:notify_campfire'].invoke
  end
  
  task :migrations => [:push, :off, :migrate, :restart, :on, :tag]
  task :rollback => [:off, :push_previous, :restart, :on]
  
  task :cache_assets => :environment do
    AssetCacheWriter.cache_javascript_and_stylesheets
  end
  
  task :commit_cached_assets => :environment do
    `git add public/stylesheets/merged/application.css`
    `git add public/javascripts/merged/application.js`
    `git add public/stylesheets/merged/small_screen.css`
    `git commit -m 'Updated static cache of CSS and JS for deploy'`
  end
  
  task :migrate do
    puts 'Running database migrations ...'
    puts `heroku rake db:migrate`
  end
  
  task :off do
    puts 'Putting the app into maintenance mode ...'
    puts `heroku maintenance:on`
  end
  
  task :on do
    puts 'Taking the app out of maintenance mode ...'
    puts `heroku maintenance:off`
  end
  
  desc 'notifies campfire room of deploy'
  task :notify_campfire do
    begin
      require 'tinder'

      rails_env = fetch(:rails_env, "production")
      local_user = ENV['USER'] || ENV['USERNAME']

      msg = "[*****] deployed by #{local_user} at #{Time.now}"
      puts "Notifying Campfire with '#{msg}'"

      campfire = Tinder::Campfire.new 'XXXXXX', :token => '************'

      room = campfire.find_room_by_name('*******')
      room.speak(msg)
    rescue
      puts "Notifying Campfire failed: #{$!}"
    end
  end
  
end

class AssetCacheWriter
  
  def initialize(file_name)
    @cached_file_name = file_name
    @path = File.join(Rails.root.to_s,'public',@cached_file_name)
    @extname = File.extname(@cached_file_name)
  end
  
  def mime_type
    {
      '.js' => 'text/javascript',
      '.css' => 'text/css'
    }[@extname]
  end
  
  def javascript?
    mime_type == 'text/javascript'
  end
  
  def minify
    if javascript?
      compressor = YUI::JavaScriptCompressor.new(:munge => true)
    else
      compressor = YUI::CssCompressor.new
    end
    File.open(@path, 'r') {|file| @minified_js = compressor.compress(file) }
    File.open(@path, 'w') {|file| file.puts @minified_js }
  end
  
  class << self
    def trigger_cache
      `rm public/stylesheets/merged/application.css` if File.exists?('public/stylesheets/merged/application.css')
      `rm public/javascripts/merged/application.js` if File.exists?('public/javascripts/merged/application.js')
      `rm public/stylesheets/merged/small_screen.css` if File.exists?('public/stylesheets/merged/small_screen.css')
      app = ActionDispatch::Integration::Session.new(MyApp::Application)
      app.get '/'
    #  app.follow_redirect!
    end
    
    def cache_javascript_and_stylesheets
      AssetCacheWriter.trigger_cache
      ['javascripts/merged/application.js', 'stylesheets/merged/application.css', 'stylesheets/merged/small_screen.css'].each do |cached_file|
        puts cached_file
        if File.exists?('public/'+cached_file)
          cacher = AssetCacheWriter.new(cached_file)
          cacher.minify
        end
      end
    end    
  end
end