ruby-on-rails – 忽略Rails 3.2 asset_host设置

# Code is not reloaded between requests
  config.cache_classes = true
  config.assets.enabled = true

  # Full error reports are disabled and caching is turned on
  config.consider_all_requests_local       = false
  config.action_controller.perform_caching = true

  # Disable Rails's static asset server (Apache or nginx will already do this)
  config.serve_static_assets = true
  config.static_cache_control = "public,max-age=31536000"

  # Compress JavaScripts and CSS
  config.assets.compress = true
  config.assets.js_compressor  = :uglifier
  #config.assets.css_compressor = :yui

  # Don't fallback to assets pipeline if a precompiled asset is missed
  config.assets.compile = true

  # Generate digests for assets URLs
  config.assets.digest = true

  # See everything in the log (default is :info)
  config.log_level = :warn
  config.log_tags = [:remote_ip,lambda { |req| Time.now }]

  # Enable serving of images,stylesheets,and JavaScripts from an asset server
  ActionController::Base.asset_host = Proc.new { |source|
    unless source.starts_with?('/stylesheets' || '/javascripts')
      "//dddd.cloudfront.net/"
    end
   }

但是,当我使用image_tag时,它仍然返回我的’/ assets ..’相对url而不是绝对url到资产主机.

irb(main):034:0> helper.image_tag('noimage.gif')
=> "<img alt="Noimage" src="/assets/noimage.gif" />"
irb(main):035:0> helper.image_path('noimage.gif')

我似乎无法想象可能会遗漏的东西.我甚至尝试过简单的config.asset_host设置,但仍然无法识别设置.