diff options
Diffstat (limited to 'actionpack/lib/action_view/helpers/asset_tag_helper.rb')
| -rw-r--r-- | actionpack/lib/action_view/helpers/asset_tag_helper.rb | 71 |
1 files changed, 68 insertions, 3 deletions
diff --git a/actionpack/lib/action_view/helpers/asset_tag_helper.rb b/actionpack/lib/action_view/helpers/asset_tag_helper.rb index 02ad41719b..e4ec17467e 100644 --- a/actionpack/lib/action_view/helpers/asset_tag_helper.rb +++ b/actionpack/lib/action_view/helpers/asset_tag_helper.rb @@ -108,7 +108,7 @@ module ActionView # "http://asset%d.example.com", "https://asset1.example.com" # ) # - # === Using asset timestamps + # === Customizing the asset path # # By default, Rails appends asset's timestamps to all asset paths. This allows # you to set a cache-expiration date for the asset far into the future, but @@ -133,6 +133,65 @@ module ActionView # will request the same assets over and over again even thought they didn't # change. You can use something like Live HTTP Headers for Firefox to verify # that the cache is indeed working. + # + # This strategy works well enough for most server setups and requires the + # least configuration, but if you deploy several application servers at + # different times - say to handle a temporary spike in load - then the + # asset time stamps will be out of sync. In a setup like this you may want + # to set the way that asset paths are generated yourself. + # + # Altering the asset paths that Rails generates can be done in two ways. + # The easiest is to define the RAILS_ASSET_ID environment variable. The + # contents of this variable will always be used in preference to + # calculated timestamps. A more complex but flexible way is to set + # <tt>ActionController::Base.config.asset_path</tt> to a proc + # that takes the unmodified asset path and returns the path needed for + # your asset caching to work. Typically you'd do something like this in + # <tt>config/environments/production.rb</tt>: + # + # # Normally you'd calculate RELEASE_NUMBER at startup. + # RELEASE_NUMBER = 12345 + # config.action_controller.asset_path_template = proc { |asset_path| + # "/release-#{RELEASE_NUMBER}#{asset_path}" + # } + # + # This example would cause the following behaviour on all servers no + # matter when they were deployed: + # + # image_tag("rails.png") + # # => <img alt="Rails" src="/release-12345/images/rails.png" /> + # stylesheet_link_tag("application") + # # => <link href="/release-12345/stylesheets/application.css?1232285206" media="screen" rel="stylesheet" type="text/css" /> + # + # Changing the asset_path does require that your web servers have + # knowledge of the asset template paths that you rewrite to so it's not + # suitable for out-of-the-box use. To use the example given above you + # could use something like this in your Apache VirtualHost configuration: + # + # <LocationMatch "^/release-\d+/(images|javascripts|stylesheets)/.*$"> + # # Some browsers still send conditional-GET requests if there's a + # # Last-Modified header or an ETag header even if they haven't + # # reached the expiry date sent in the Expires header. + # Header unset Last-Modified + # Header unset ETag + # FileETag None + # + # # Assets requested using a cache-busting filename should be served + # # only once and then cached for a really long time. The HTTP/1.1 + # # spec frowns on hugely-long expiration times though and suggests + # # that assets which never expire be served with an expiration date + # # 1 year from access. + # ExpiresActive On + # ExpiresDefault "access plus 1 year" + # </LocationMatch> + # + # # We use cached-busting location names with the far-future expires + # # headers to ensure that if a file does change it can force a new + # # request. The actual asset filenames are still the same though so we + # # need to rewrite the location from the cache-busting location to the + # # real asset location so that we can serve it. + # RewriteEngine On + # RewriteRule ^/release-\d+/(images|javascripts|stylesheets)/(.*)$ /$1/$2 [L] module AssetTagHelper JAVASCRIPT_DEFAULT_SOURCES = ['prototype', 'effects', 'dragdrop', 'controls', 'rails'].freeze unless const_defined?(:JAVASCRIPT_DEFAULT_SOURCES) @@ -646,7 +705,7 @@ module ActionView source += ".#{ext}" if rewrite_extension?(source, dir, ext) source = "/#{dir}/#{source}" unless source[0] == ?/ - source = rewrite_asset_path(source) + source = rewrite_asset_path(source, config.asset_path) has_request = controller.respond_to?(:request) if has_request && include_host && source !~ %r{^#{controller.config.relative_url_root}/} @@ -710,7 +769,13 @@ module ActionView # Break out the asset path rewrite in case plugins wish to put the asset id # someplace other than the query string. - def rewrite_asset_path(source) + def rewrite_asset_path(source, path = nil) + if path && path.respond_to?(:call) + return path.call(source) + elsif path && path.is_a?(String) + return path % [source] + end + asset_id = rails_asset_id(source) if asset_id.blank? source |