From 5371106d530e64cfb221492714fb7cef32fa45c3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hubert=20=C5=81=C4=99picki?= <hubert.lepicki@amberbit.com>
Date: Thu, 8 May 2014 08:05:45 +0200
Subject: Allow custom asset host to be passed in asset_url

---
 actionview/lib/action_view/helpers/asset_url_helper.rb |  3 ++-
 actionview/test/template/asset_tag_helper_test.rb      | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/actionview/lib/action_view/helpers/asset_url_helper.rb b/actionview/lib/action_view/helpers/asset_url_helper.rb
index 41997a85b3..86a84c1356 100644
--- a/actionview/lib/action_view/helpers/asset_url_helper.rb
+++ b/actionview/lib/action_view/helpers/asset_url_helper.rb
@@ -191,7 +191,8 @@ module ActionView
       # (proc or otherwise).
       def compute_asset_host(source = "", options = {})
         request = self.request if respond_to?(:request)
-        host = config.asset_host if defined? config.asset_host
+        host = options[:host]
+        host ||= config.asset_host if defined? config.asset_host
         host ||= request.base_url if request && options[:protocol] == :request
 
         if host.respond_to?(:call)
diff --git a/actionview/test/template/asset_tag_helper_test.rb b/actionview/test/template/asset_tag_helper_test.rb
index 18e4277d7a..343681b5a9 100644
--- a/actionview/test/template/asset_tag_helper_test.rb
+++ b/actionview/test/template/asset_tag_helper_test.rb
@@ -596,6 +596,10 @@ class AssetTagHelperNonVhostTest < ActionView::TestCase
     assert_equal "gopher://www.example.com", compute_asset_host("foo", :protocol => :request)
   end
 
+  def test_should_return_custom_host_if_passed_in_options
+    assert_equal "http://custom.example.com", compute_asset_host("foo", :host => "http://custom.example.com")
+  end
+
   def test_should_ignore_relative_root_path_on_complete_url
     assert_dom_equal(%(http://www.example.com/images/xml.png), image_path("http://www.example.com/images/xml.png"))
   end
@@ -759,4 +763,15 @@ class AssetUrlHelperEmptyModuleTest < ActionView::TestCase
     assert @module.config.asset_host
     assert_equal "http://www.example.com/foo", @module.asset_url("foo")
   end
+
+  def test_asset_url_with_custom_asset_host
+    @module.instance_eval do
+      def config
+        Struct.new(:asset_host).new("http://www.example.com")
+      end
+    end
+
+    assert @module.config.asset_host
+    assert_equal "http://custom.example.com/foo", @module.asset_url("foo", :host => "http://custom.example.com")
+  end
 end
-- 
cgit v1.2.3


From db9a5c5a1f8e2a1590f0ac9436587d58a67a629e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hubert=20=C5=81=C4=99picki?= <hubert.lepicki@amberbit.com>
Date: Thu, 8 May 2014 13:35:31 +0200
Subject: Improve documentation for asset_url

Updated CHANGELOG.md with entry about :host in asset_url
---
 actionview/CHANGELOG.md                                | 4 ++++
 actionview/lib/action_view/helpers/asset_url_helper.rb | 9 ++++++++-
 guides/source/asset_pipeline.md                        | 8 ++++++++
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/actionview/CHANGELOG.md b/actionview/CHANGELOG.md
index a6f6ac78db..36028122d1 100644
--- a/actionview/CHANGELOG.md
+++ b/actionview/CHANGELOG.md
@@ -87,5 +87,9 @@
 
     *Piotr Chmolowski, Łukasz Strzałkowski*
 
+*   Allow custom `:host` option to be passed to `asset_url` helper that
+    overwrites `config.action_controller.asset_host` for particular asset.
+
+    *Hubert Łępicki*
 
 Please check [4-1-stable](https://github.com/rails/rails/blob/4-1-stable/actionview/CHANGELOG.md) for previous changes.
diff --git a/actionview/lib/action_view/helpers/asset_url_helper.rb b/actionview/lib/action_view/helpers/asset_url_helper.rb
index 86a84c1356..ae684af87b 100644
--- a/actionview/lib/action_view/helpers/asset_url_helper.rb
+++ b/actionview/lib/action_view/helpers/asset_url_helper.rb
@@ -147,7 +147,14 @@ module ActionView
 
       # Computes the full URL to an asset in the public directory. This
       # will use +asset_path+ internally, so most of their behaviors
-      # will be the same.
+      # will be the same. If :host options is set, it overwrites global
+      # +config.action_controller.asset_host+ setting.
+      #
+      # All other options provided are forwarded to +asset_path+ call.
+      #
+      #   asset_url "application.js"                                 # => http://example.com/application.js
+      #   asset_url "application.js", host: "http://cdn.example.com" # => http://cdn.example.com/javascripts/application.js
+      #
       def asset_url(source, options = {})
         path_to_asset(source, options.merge(:protocol => :request))
       end
diff --git a/guides/source/asset_pipeline.md b/guides/source/asset_pipeline.md
index 52fc9726d9..950cfdca29 100644
--- a/guides/source/asset_pipeline.md
+++ b/guides/source/asset_pipeline.md
@@ -913,6 +913,14 @@ that it plays nicely with the pipeline. You may find quirks related to your
 specific set up, you may not. The defaults nginx uses, for example, should give
 you no problems when used as an HTTP cache.
 
+If you want to serve only some assets from your CDN, you can use custom
+`:host` option of  `asset_url` helper, which overwrites value set in
+`config.action_controller.asset_host`.
+
+```ruby
+asset_url 'image.png', :host => 'http://cdn.example.com'
+```
+
 Customizing the Pipeline
 ------------------------
 
-- 
cgit v1.2.3