1 files changed, 38 insertions, 2 deletions
diff --git a/guides/source/caching_with_rails.textile b/guides/source/caching_with_rails.textile
index 0e811a2527..34a100cd3a 100644
--- a/guides/source/caching_with_rails.textile
+++ b/guides/source/caching_with_rails.textile
@@ -92,7 +92,7 @@ INFO: Page caching runs in an after filter. Thus, invalid requests won't generat
 
 h4. Action Caching
 
-One of the issues with Page Caching is that you cannot use it for pages that require to restrict access somehow. This is where Action Caching comes in. Action Caching works like Page Caching except for the fact that the incoming web request does go from the webserver to the Rails stack and Action Pack so that before filters can be run on it before the cache is served. This allows authentication and other restriction to be run while still serving the result of the output from a cached copy.
+Page Caching cannot be used for actions that have before filters - for example, pages that require authentication. This is where Action Caching comes in. Action Caching works like Page Caching except the incoming web request hits the Rails stack so that before filters can be run on it before the cache is served. This allows authentication and other restrictions to be run while still serving the result of the output from a cached copy.
 
 Clearing the cache works in a similar way to Page Caching, except you use +expire_action+ instead of +expire_page+.
 
@@ -157,7 +157,7 @@ and you can expire it using the +expire_fragment+ method, like so:
 expire_fragment(:controller => 'products', :action => 'recent', :action_suffix => 'all_products')
 </ruby>
 
-If you don't want the cache block to bind to the action that called it, You can also use globally keyed fragments by calling the +cache+ method with a key, like so:
+If you don't want the cache block to bind to the action that called it, you can also use globally keyed fragments by calling the +cache+ method with a key:
 
 <ruby>
 <% cache('all_available_products') do %>
@@ -229,6 +229,42 @@ class ProductsController < ActionController
 end
 </ruby>
 
+Sometimes it is necessary to disambiguate the controller when you call +expire_action+, such as when there are two identically named controllers in separate namespaces:
+
+<ruby>
+class ProductsController < ActionController
+  caches_action :index
+
+  def index
+    @products = Product.all
+  end
+end
+
+module Admin
+  class ProductsController < ActionController
+    cache_sweeper :product_sweeper
+
+    def new
+      @product = Product.new
+    end
+
+    def create
+      @product = Product.create(params[:product])
+    end
+  end
+end
+
+class ProductSweeper < ActionController::Caching::Sweeper
+  observe Product
+
+  def after_create(product)
+    expire_action(:controller => '/products', :action => 'index')
+  end
+end
+</ruby>
+
+Note the use of '/products' here rather than 'products'. If you wanted to expire an action cache for the +Admin::ProductsController+, you would use 'admin/products' instead.
+
 h4. SQL Caching
 
 Query caching is a Rails feature that caches the result set returned by each query so that if Rails encounters the same query again for that request, it will use the cached result set as opposed to running the query against the database again.