From dbf3666964b8f2a536476cd598492cb3f7aaab47 Mon Sep 17 00:00:00 2001
From: Ary Djmal <arydjmal@gmail.com>
Date: Mon, 11 Oct 2010 15:14:25 -0400
Subject: [PATCH] Added support to action-cache json requests wrapped in a callback (jsonp)

---
 .../lib/action_controller/caching/actions.rb       |    7 ++++++
 actionpack/test/controller/caching_test.rb         |   22 +++++++++++++++++++-
 2 files changed, 28 insertions(+), 1 deletions(-)

diff --git a/actionpack/lib/action_controller/caching/actions.rb b/actionpack/lib/action_controller/caching/actions.rb
index d69d96b..a926e6d 100644
--- a/actionpack/lib/action_controller/caching/actions.rb
+++ b/actionpack/lib/action_controller/caching/actions.rb
@@ -133,11 +133,18 @@ module ActionController #:nodoc:
             body = controller._save_fragment(cache_path.path, @store_options)
           end
 
+          body = reset_json_callback(body, controller.params[:callback]) if controller.request.format.json?
           body = controller.render_to_string(:text => body, :layout => true) unless @cache_layout
 
           controller.response_body = body
           controller.content_type = Mime[cache_path.extension || :html]
         end
+
+      private
+        def reset_json_callback(body, callback)
+          body = body.sub(/^\w+\((.*)\)$/, '\1')
+          callback.present? ? "#{callback}(#{body})" : body
+        end
       end
 
       class ActionCachePath
diff --git a/actionpack/test/controller/caching_test.rb b/actionpack/test/controller/caching_test.rb
index 914ae56..da0d350 100644
--- a/actionpack/test/controller/caching_test.rb
+++ b/actionpack/test/controller/caching_test.rb
@@ -163,7 +163,7 @@ class ActionCachingTestController < CachingController
   caches_action :index, :redirected, :forbidden, :if => Proc.new { |c| !c.request.format.json? }, :expires_in => 1.hour
   caches_action :show, :cache_path => 'http://test.host/custom/show'
   caches_action :edit, :cache_path => Proc.new { |c| c.params[:id] ? "http://test.host/#{c.params[:id]};edit" : "http://test.host/edit" }
-  caches_action :with_layout
+  caches_action :with_json_callback, :with_layout
   caches_action :layout_false, :layout => false
   caches_action :record_not_found, :four_oh_four, :simple_runtime_error
 
@@ -183,6 +183,11 @@ class ActionCachingTestController < CachingController
     response.status = "403 Forbidden"
   end
 
+  def with_json_callback
+    @cache_this = MockTime.now.to_f.to_s
+    render :json => @cache_this, :callback => params[:callback]
+  end
+
   def with_layout
     @cache_this = MockTime.now.to_f.to_s
     @title = nil
@@ -362,6 +367,21 @@ class ActionCacheTest < ActionController::TestCase
     assert fragment_exist?('test.host/1;edit')
   end
 
+  def test_action_cache_with_json_callback
+    @request.env['HTTP_ACCEPT'] = 'application/json'
+    get :with_json_callback, :callback => 'jsonp123456789'
+    cached_time = content_to_cache
+    assert_equal "jsonp123456789(#{cached_time})", @response.body
+    assert fragment_exist?('hostname.com/action_caching_test/with_json_callback')
+
+    get :with_json_callback, :callback => 'jsonp987654321'
+    assert_equal "jsonp987654321(#{cached_time})", @response.body
+    assert_equal "jsonp123456789(#{cached_time})", read_fragment('hostname.com/action_caching_test/with_json_callback')
+
+    get :with_json_callback
+    assert_equal cached_time, @response.body
+  end
+
   def test_cache_expiration
     get :index
     assert_response :success
-- 
1.7.1