Moved the caching stores from ActionController::Caching::Fragments::* to ActiveSupport::Cache::*. If you're explicitly referring to a store, like ActionController::Caching::Fragments::MemoryStore, you need to update that reference with ActiveSupport::Cache::MemoryStore [DHH] Deprecated ActionController::Base.fragment_cache_store for ActionController::Base.cache_store [DHH] All fragment cache keys are now by default prefixed with the 'views/' namespace [DHH] Added ActiveRecord::Base.cache_key to make it easier to cache Active Records in combination with the new ActiveSupport::Cache::* libraries [DHH] Added ActiveSupport::Gzip.decompress/compress(source) as an easy wrapper for Zlib [Tobias Luetke] Included MemCache-Client to make the improved ActiveSupport::Cache::MemCacheStore work out of the box [Bob Cottrell, Eric Hodel] Added config.cache_store to environment options to control the default cache store (default is FileStore if tmp/cache is present, otherwise MemoryStore is used) [DHH]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8546 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 40 insertions, 678 deletions

diff --git a/actionpack/lib/action_controller/caching.rb b/actionpack/lib/action_controller/caching.rb
index 024f633d7c..7929886781 100644
--- a/actionpack/lib/action_controller/caching.rb
+++ b/actionpack/lib/action_controller/caching.rb
@@ -2,6 +2,13 @@ require 'fileutils'
 require 'uri'
 require 'set'
 
+require 'action_controller/caching/pages'
+require 'action_controller/caching/actions'
+require 'action_controller/caching/sql_cache'
+require 'action_controller/caching/sweeping'
+require 'action_controller/caching/fragments'
+
+
 module ActionController #:nodoc:
   # Caching is a cheap way of speeding up slow applications by keeping the result of calculations, renderings, and database calls
   # around for subsequent requests. Action Controller affords you three approaches in varying levels of granularity: Page, Action, Fragment.
@@ -9,701 +16,56 @@ module ActionController #:nodoc:
   # You can read more about each approach and the sweeping assistance by clicking the modules below.
   #
   # Note: To turn off all caching and sweeping, set Base.perform_caching = false.
+  #
+  #
+  # == Caching stores
+  #
+  # All the caching stores from ActiveSupport::Cache is available to be used as backends for Action Controller caching.
+  #
+  # Configuration examples (MemoryStore is the default):
+  #
+  #   ActionController::Base.cache_store = :memory_store
+  #   ActionController::Base.cache_store = :file_store, "/path/to/cache/directory"
+  #   ActionController::Base.cache_store = :drb_store, "druby://localhost:9192"
+  #   ActionController::Base.cache_store = :mem_cache_store, "localhost"
+  #   ActionController::Base.cache_store = MyOwnStore.new("parameter")
   module Caching
     def self.included(base) #:nodoc:
       base.class_eval do
-        include Pages, Actions, Fragments
+        @@cache_store = nil
+        cattr_reader :cache_store
 
-        if defined? ActiveRecord
-          include Sweeping, SqlCache
+        # Defines the storage option for cached fragments
+        def self.cache_store=(store_option)
+          @@cache_store = ActiveSupport::Cache.lookup_store(store_option)
         end
 
+        include Pages, Actions, Fragments
+        include Sweeping, SqlCache if defined?(ActiveRecord)
+
         @@perform_caching = true
         cattr_accessor :perform_caching
-      end
-    end
-
-    # Page caching is an approach to caching where the entire action output of is stored as a HTML file that the web server
-    # can serve without going through the Action Pack. This can be as much as 100 times faster than going through the process of dynamically
-    # generating the content. Unfortunately, this incredible speed-up is only available to stateless pages where all visitors
-    # are treated the same. Content management systems -- including weblogs and wikis -- have many pages that are a great fit
-    # for this approach, but account-based systems where people log in and manipulate their own data are often less likely candidates.
-    #
-    # Specifying which actions to cache is done through the <tt>caches</tt> class method:
-    #
-    #   class WeblogController < ActionController::Base
-    #     caches_page :show, :new
-    #   end
-    #
-    # This will generate cache files such as weblog/show/5 and weblog/new, which match the URLs used to trigger the dynamic
-    # generation. This is how the web server is able pick up a cache file when it exists and otherwise let the request pass on to
-    # the Action Pack to generate it.
-    #
-    # Expiration of the cache is handled by deleting the cached file, which results in a lazy regeneration approach where the cache
-    # is not restored before another hit is made against it. The API for doing so mimics the options from url_for and friends:
-    #
-    #   class WeblogController < ActionController::Base
-    #     def update
-    #       List.update(params[:list][:id], params[:list])
-    #       expire_page :action => "show", :id => params[:list][:id]
-    #       redirect_to :action => "show", :id => params[:list][:id]
-    #     end
-    #   end
-    #
-    # Additionally, you can expire caches using Sweepers that act on changes in the model to determine when a cache is supposed to be
-    # expired.
-    #
-    # == Setting the cache directory
-    #
-    # The cache directory should be the document root for the web server and is set using Base.page_cache_directory = "/document/root".
-    # For Rails, this directory has already been set to RAILS_ROOT + "/public".
-    #
-    # == Setting the cache extension
-    #
-    # By default, the cache extension is .html, which makes it easy for the cached files to be picked up by the web server. If you want
-    # something else, like .php or .shtml, just set Base.page_cache_extension.
-    module Pages
-      def self.included(base) #:nodoc:
-        base.extend(ClassMethods)
-        base.class_eval do
-          @@page_cache_directory = defined?(RAILS_ROOT) ? "#{RAILS_ROOT}/public" : ""
-          cattr_accessor :page_cache_directory
-
-          @@page_cache_extension = '.html'
-          cattr_accessor :page_cache_extension
-        end
-      end
-
-      module ClassMethods
-        # Expires the page that was cached with the +path+ as a key. Example:
-        #   expire_page "/lists/show"
-        def expire_page(path)
-          return unless perform_caching
-
-          benchmark "Expired page: #{page_cache_file(path)}" do
-            File.delete(page_cache_path(path)) if File.exist?(page_cache_path(path))
-          end
-        end
-
-        # Manually cache the +content+ in the key determined by +path+. Example:
-        #   cache_page "I'm the cached content", "/lists/show"
-        def cache_page(content, path)
-          return unless perform_caching
-
-          benchmark "Cached page: #{page_cache_file(path)}" do
-            FileUtils.makedirs(File.dirname(page_cache_path(path)))
-            File.open(page_cache_path(path), "wb+") { |f| f.write(content) }
-          end
-        end
 
-        # Caches the +actions+ using the page-caching approach that'll store the cache in a path within the page_cache_directory that
-        # matches the triggering url.
-        def caches_page(*actions)
-          return unless perform_caching
-          actions = actions.map(&:to_s)
-          after_filter { |c| c.cache_page if actions.include?(c.action_name) }
+        def self.cache_configured?
+          perform_caching && cache_store
         end
-
-        private
-          def page_cache_file(path)
-            name = (path.empty? || path == "/") ? "/index" : URI.unescape(path.chomp('/'))
-            name << page_cache_extension unless (name.split('/').last || name).include? '.'
-            return name
-          end
-
-          def page_cache_path(path)
-            page_cache_directory + page_cache_file(path)
-          end
       end
-
-      # Expires the page that was cached with the +options+ as a key. Example:
-      #   expire_page :controller => "lists", :action => "show"
-      def expire_page(options = {})
-        return unless perform_caching
-
-        if options.is_a?(Hash)
-          if options[:action].is_a?(Array)
-            options[:action].dup.each do |action|
-              self.class.expire_page(url_for(options.merge(:only_path => true, :skip_relative_url_root => true, :action => action)))
-            end
-          else
-            self.class.expire_page(url_for(options.merge(:only_path => true, :skip_relative_url_root => true)))
-          end
-        else
-          self.class.expire_page(options)
-        end
-      end
-
-      # Manually cache the +content+ in the key determined by +options+. If no content is provided, the contents of response.body is used
-      # If no options are provided, the requested url is used. Example:
-      #   cache_page "I'm the cached content", :controller => "lists", :action => "show"
-      def cache_page(content = nil, options = nil)
-        return unless perform_caching && caching_allowed
-
-        path = case options
-          when Hash
-            url_for(options.merge(:only_path => true, :skip_relative_url_root => true, :format => params[:format]))
-          when String
-            options
-          else
-            request.path
-        end
-
-        self.class.cache_page(content || response.body, path)
-      end
-
-      private
-        def caching_allowed
-          request.get? && response.headers['Status'].to_i == 200
-        end
     end
 
-    # Action caching is similar to page caching by the fact that the entire output of the response is cached, but unlike page caching,
-    # every request still goes through the Action Pack. The key benefit of this is that filters are run before the cache is served, which
-    # allows for authentication and other restrictions on whether someone is allowed to see the cache. Example:
-    #
-    #   class ListsController < ApplicationController
-    #     before_filter :authenticate, :except => :public
-    #     caches_page   :public
-    #     caches_action :show, :feed
-    #   end
-    #
-    # In this example, the public action doesn't require authentication, so it's possible to use the faster page caching method. But both the
-    # show and feed action are to be shielded behind the authenticate filter, so we need to implement those as action caches.
-    #
-    # Action caching internally uses the fragment caching and an around filter to do the job. The fragment cache is named according to both
-    # the current host and the path. So a page that is accessed at http://david.somewhere.com/lists/show/1 will result in a fragment named
-    # "david.somewhere.com/lists/show/1". This allows the cacher to differentiate between "david.somewhere.com/lists/" and
-    # "jamis.somewhere.com/lists/" -- which is a helpful way of assisting the subdomain-as-account-key pattern.
-    #
-    # Different representations of the same resource, e.g. <tt>http://david.somewhere.com/lists</tt> and <tt>http://david.somewhere.com/lists.xml</tt>
-    # are treated like separate requests and so are cached separately. Keep in mind when expiring an action cache that <tt>:action => 'lists'</tt> is not the same
-    # as <tt>:action => 'list', :format => :xml</tt>.
-    #
-    # You can set modify the default action cache path by passing a :cache_path option.  This will be passed directly to ActionCachePath.path_for.  This is handy
-    # for actions with multiple possible routes that should be cached differently.  If a block is given, it is called with the current controller instance.
-    #
-    #   class ListsController < ApplicationController
-    #     before_filter :authenticate, :except => :public
-    #     caches_page   :public
-    #     caches_action :show, :cache_path => { :project => 1 }
-    #     caches_action :show, :cache_path => Proc.new { |controller| 
-    #       controller.params[:user_id] ? 
-    #         controller.send(:user_list_url, c.params[:user_id], c.params[:id]) :
-    #         controller.send(:list_url, c.params[:id]) }
-    #   end
-    module Actions
-      def self.included(base) #:nodoc:
-        base.extend(ClassMethods)
-          base.class_eval do
-            attr_accessor :rendered_action_cache, :action_cache_path
-            alias_method_chain :protected_instance_variables, :action_caching
-          end
-      end
-
-      module ClassMethods
-        # Declares that +actions+ should be cached.
-        # See ActionController::Caching::Actions for details.
-        def caches_action(*actions)
-          return unless perform_caching
-          around_filter(ActionCacheFilter.new(*actions))
-        end
-      end
-
-      def protected_instance_variables_with_action_caching
-        protected_instance_variables_without_action_caching + %w(@action_cache_path)
-      end
-
-      def expire_action(options = {})
-        return unless perform_caching
-        if options[:action].is_a?(Array)
-          options[:action].dup.each do |action|
-            expire_fragment(ActionCachePath.path_for(self, options.merge({ :action => action })))
-          end
+    protected
+      # Convenience accessor
+      def cache(key, options = nil, &block)
+        if cache_configured?
+          cache_store.fetch(ActiveSupport::Cache.expand_cache_key(key, :controller), options, &block)
         else
-          expire_fragment(ActionCachePath.path_for(self, options))
+          yield
         end
       end
 
-      class ActionCacheFilter #:nodoc:
-        def initialize(*actions, &block)
-          @options = actions.extract_options!
-          @actions = Set.new actions
-        end
-
-        def before(controller)
-          return unless @actions.include?(controller.action_name.intern)
-          cache_path = ActionCachePath.new(controller, path_options_for(controller, @options))
-          if cache = controller.read_fragment(cache_path.path)
-            controller.rendered_action_cache = true
-            set_content_type!(controller, cache_path.extension)
-            controller.send!(:render_for_text, cache)
-            false
-          else
-            controller.action_cache_path = cache_path
-          end
-        end
-
-        def after(controller)
-          return if !@actions.include?(controller.action_name.intern) || controller.rendered_action_cache || !caching_allowed(controller)
-          controller.write_fragment(controller.action_cache_path.path, controller.response.body)
-        end
 
-        private
-          def set_content_type!(controller, extension)
-            controller.response.content_type = Mime::Type.lookup_by_extension(extension).to_s if extension
-          end
-
-          def path_options_for(controller, options)
-            ((path_options = options[:cache_path]).respond_to?(:call) ? path_options.call(controller) : path_options) || {}
-          end
-
-          def caching_allowed(controller)
-            controller.request.get? && controller.response.headers['Status'].to_i == 200
-          end
-      end
-      
-      class ActionCachePath
-        attr_reader :path, :extension
-        
-        class << self
-          def path_for(controller, options)
-            new(controller, options).path
-          end
-        end
-        
-        def initialize(controller, options = {})
-          @extension = extract_extension(controller.request.path)
-          path = controller.url_for(options).split('://').last
-          normalize!(path)
-          add_extension!(path, @extension)
-          @path = URI.unescape(path)
-        end
-        
-        private
-          def normalize!(path)
-            path << 'index' if path[-1] == ?/
-          end
-        
-          def add_extension!(path, extension)
-            path << ".#{extension}" if extension
-          end
-          
-          def extract_extension(file_path)
-            # Don't want just what comes after the last '.' to accommodate multi part extensions
-            # such as tar.gz.
-            file_path[/^[^.]+\.(.+)$/, 1]
-          end
+    private    
+      def cache_configured?
+        self.class.cache_configured?
       end
-    end
-
-    # Fragment caching is used for caching various blocks within templates without caching the entire action as a whole. This is useful when
-    # certain elements of an action change frequently or depend on complicated state while other parts rarely change or can be shared amongst multiple
-    # parties. The caching is doing using the cache helper available in the Action View. A template with caching might look something like:
-    #
-    #   <b>Hello <%= @name %></b>
-    #   <% cache do %>
-    #     All the topics in the system:
-    #     <%= render :partial => "topic", :collection => Topic.find(:all) %>
-    #   <% end %>
-    #
-    # This cache will bind to the name of the action that called it, so if this code was part of the view for the topics/list action, you would 
-    # be able to invalidate it using <tt>expire_fragment(:controller => "topics", :action => "list")</tt>. 
-    # 
-    # This default behavior is of limited use if you need to cache multiple fragments per action or if the action itself is cached using 
-    # <tt>caches_action</tt>, so we also have the option to qualify the name of the cached fragment with something like:
-    #
-    #   <% cache(:action => "list", :action_suffix => "all_topics") do %>
-    #
-    # That would result in a name such as "/topics/list/all_topics", avoiding conflicts with the action cache and with any fragments that use a 
-    # different suffix. Note that the URL doesn't have to really exist or be callable - the url_for system is just used to generate unique 
-    # cache names that we can refer to when we need to expire the cache. 
-    # 
-    # The expiration call for this example is:
-    # 
-    #   expire_fragment(:controller => "topics", :action => "list", :action_suffix => "all_topics")
-    #
-    # == Fragment stores
-    #
-    # By default, cached fragments are stored in memory. The available store options are:
-    #
-    # * FileStore: Keeps the fragments on disk in the +cache_path+, which works well for all types of environments and allows all 
-    #   processes running from the same application directory to access the cached content.
-    # * MemoryStore: Keeps the fragments in memory, which is fine for WEBrick and for FCGI (if you don't care that each FCGI process holds its
-    #   own fragment store). It's not suitable for CGI as the process is thrown away at the end of each request. It can potentially also take
-    #   up a lot of memory since each process keeps all the caches in memory.
-    # * DRbStore: Keeps the fragments in the memory of a separate, shared DRb process. This works for all environments and only keeps one cache
-    #   around for all processes, but requires that you run and manage a separate DRb process.
-    # * MemCacheStore: Works like DRbStore, but uses Danga's MemCache instead.
-    #   Requires the ruby-memcache library:  gem install ruby-memcache.
-    #
-    # Configuration examples (MemoryStore is the default):
-    #
-    #   ActionController::Base.fragment_cache_store = :memory_store
-    #   ActionController::Base.fragment_cache_store = :file_store, "/path/to/cache/directory"
-    #   ActionController::Base.fragment_cache_store = :drb_store, "druby://localhost:9192"
-    #   ActionController::Base.fragment_cache_store = :mem_cache_store, "localhost"
-    #   ActionController::Base.fragment_cache_store = MyOwnStore.new("parameter")
-    module Fragments
-      def self.included(base) #:nodoc:
-        base.class_eval do
-          @@fragment_cache_store = MemoryStore.new
-          cattr_reader :fragment_cache_store
-
-          # Defines the storage option for cached fragments
-          def self.fragment_cache_store=(store_option)
-            store, *parameters = *([ store_option ].flatten)
-            @@fragment_cache_store = if store.is_a?(Symbol)
-              store_class_name = (store == :drb_store ? "DRbStore" : store.to_s.camelize)
-              store_class = ActionController::Caching::Fragments.const_get(store_class_name)
-              store_class.new(*parameters)
-            else
-              store
-            end
-          end
-        end
-      end
-
-      # Given a name (as described in <tt>expire_fragment</tt>), returns a key suitable for use in reading, 
-      # writing, or expiring a cached fragment. If the name is a hash, the generated name is the return
-      # value of url_for on that hash (without the protocol).
-      def fragment_cache_key(name)
-        name.is_a?(Hash) ? url_for(name).split("://").last : name
-      end
-
-      def fragment_for(block, name = {}, options = nil) #:nodoc:
-        unless perform_caching then block.call; return end
-
-        buffer = yield
-
-        if cache = read_fragment(name, options)
-          buffer.concat(cache)
-        else
-          pos = buffer.length
-          block.call
-          write_fragment(name, buffer[pos..-1], options)
-        end
-      end
-
-      # Called by CacheHelper#cache
-      def cache_rxml_fragment(block, name = {}, options = nil) #:nodoc:
-        fragment_for(block, name, options) do
-          eval('xml.target!', block.binding)
-        end
-      end
-      
-      # Called by CacheHelper#cache
-      def cache_rjs_fragment(block, name = {}, options = nil) #:nodoc:
-        fragment_for(block, name, options) do
-          begin
-            debug_mode, ActionView::Base.debug_rjs = ActionView::Base.debug_rjs, false
-            eval('page.to_s', block.binding)
-          ensure
-            ActionView::Base.debug_rjs = debug_mode
-          end
-        end
-      end
-      
-      # Called by CacheHelper#cache
-      def cache_erb_fragment(block, name = {}, options = nil) #:nodoc:
-        fragment_for(block, name, options) do
-          eval(ActionView::Base.erb_variable, block.binding)
-        end
-      end
-
-
-      # Writes <tt>content</tt> to the location signified by <tt>name</tt> (see <tt>expire_fragment</tt> for acceptable formats)
-      def write_fragment(name, content, options = nil)
-        return unless perform_caching
-
-        key = fragment_cache_key(name)
-        self.class.benchmark "Cached fragment: #{key}" do
-          fragment_cache_store.write(key, content, options)
-        end
-        content
-      end
-
-      # Reads a cached fragment from the location signified by <tt>name</tt> (see <tt>expire_fragment</tt> for acceptable formats)
-      def read_fragment(name, options = nil)
-        return unless perform_caching
-
-        key = fragment_cache_key(name)
-        self.class.benchmark "Fragment read: #{key}" do
-          fragment_cache_store.read(key, options)
-        end
-      end
-
-      # Name can take one of three forms:
-      # * String: This would normally take the form of a path like "pages/45/notes"
-      # * Hash: Is treated as an implicit call to url_for, like { :controller => "pages", :action => "notes", :id => 45 }
-      # * Regexp: Will destroy all the matched fragments, example:
-      #     %r{pages/\d*/notes}
-      #   Ensure you do not specify start and finish in the regex (^$) because
-      #   the actual filename matched looks like ./cache/filename/path.cache
-      #   Regexp expiration is only supported on caches that can iterate over
-      #   all keys (unlike memcached).
-      def expire_fragment(name, options = nil)
-        return unless perform_caching
-
-        key = fragment_cache_key(name)
-
-        if key.is_a?(Regexp)
-          self.class.benchmark "Expired fragments matching: #{key.source}" do
-            fragment_cache_store.delete_matched(key, options)
-          end
-        else
-          self.class.benchmark "Expired fragment: #{key}" do
-            fragment_cache_store.delete(key, options)
-          end
-        end
-      end
-
-
-      class UnthreadedMemoryStore #:nodoc:
-        def initialize #:nodoc:
-          @data = {}
-        end
-
-        def read(name, options=nil) #:nodoc:
-          @data[name]
-        end
-
-        def write(name, value, options=nil) #:nodoc:
-          @data[name] = value
-        end
-
-        def delete(name, options=nil) #:nodoc:
-          @data.delete(name)
-        end
-
-        def delete_matched(matcher, options=nil) #:nodoc:
-          @data.delete_if { |k,v| k =~ matcher }
-        end
-      end
-
-      module ThreadSafety #:nodoc:
-        def read(name, options=nil) #:nodoc:
-          @mutex.synchronize { super }
-        end
-
-        def write(name, value, options=nil) #:nodoc:
-          @mutex.synchronize { super }
-        end
-
-        def delete(name, options=nil) #:nodoc:
-          @mutex.synchronize { super }
-        end
-
-        def delete_matched(matcher, options=nil) #:nodoc:
-          @mutex.synchronize { super }
-        end
-      end
-
-      class MemoryStore < UnthreadedMemoryStore #:nodoc:
-        def initialize #:nodoc:
-          super
-          if ActionController::Base.allow_concurrency
-            @mutex = Mutex.new
-            MemoryStore.module_eval { include ThreadSafety }
-          end
-        end
-      end
-
-      class DRbStore < MemoryStore #:nodoc:
-        attr_reader :address
-
-        def initialize(address = 'druby://localhost:9192')
-          super()
-          @address = address
-          @data = DRbObject.new(nil, address)
-        end
-      end
-
-    begin
-      require_library_or_gem 'memcache'
-      class MemCacheStore < MemoryStore #:nodoc:
-        attr_reader :addresses
-
-        def initialize(*addresses)
-          super()
-          addresses = addresses.flatten
-          addresses = ["localhost"] if addresses.empty?
-          @addresses = addresses
-          @data = MemCache.new(*addresses)
-        end
-      end
-    rescue LoadError
-      # MemCache wasn't available so neither can the store be
-    end
-
-      class UnthreadedFileStore #:nodoc:
-        attr_reader :cache_path
-
-        def initialize(cache_path)
-          @cache_path = cache_path
-        end
-
-        def write(name, value, options = nil) #:nodoc:
-          ensure_cache_path(File.dirname(real_file_path(name)))
-          File.open(real_file_path(name), "wb+") { |f| f.write(value) }
-        rescue => e
-          Base.logger.error "Couldn't create cache directory: #{name} (#{e.message})" if Base.logger
-        end
-
-        def read(name, options = nil) #:nodoc:
-          File.open(real_file_path(name), 'rb') { |f| f.read } rescue nil
-        end
-
-        def delete(name, options) #:nodoc:
-          File.delete(real_file_path(name))
-        rescue SystemCallError => e
-          # If there's no cache, then there's nothing to complain about
-        end
-
-        def delete_matched(matcher, options) #:nodoc:
-          search_dir(@cache_path) do |f|
-            if f =~ matcher
-              begin
-                File.delete(f)
-              rescue SystemCallError => e
-                # If there's no cache, then there's nothing to complain about
-              end
-            end
-          end
-        end
-
-        private
-          def real_file_path(name)
-            '%s/%s.cache' % [@cache_path, name.gsub('?', '.').gsub(':', '.')]
-          end
-
-          def ensure_cache_path(path)
-            FileUtils.makedirs(path) unless File.exist?(path)
-          end
-
-          def search_dir(dir, &callback)
-            Dir.foreach(dir) do |d|
-              next if d == "." || d == ".."
-              name = File.join(dir, d)
-              if File.directory?(name)
-                search_dir(name, &callback)
-              else
-                callback.call name
-              end
-            end
-          end
-        end
-
-        class FileStore < UnthreadedFileStore #:nodoc:
-          def initialize(cache_path)
-            super(cache_path)
-            if ActionController::Base.allow_concurrency
-              @mutex = Mutex.new
-              FileStore.module_eval { include ThreadSafety }
-            end
-          end
-        end
-    end
-
-    # Sweepers are the terminators of the caching world and responsible for expiring caches when model objects change.
-    # They do this by being half-observers, half-filters and implementing callbacks for both roles. A Sweeper example:
-    #
-    #   class ListSweeper < ActionController::Caching::Sweeper
-    #     observe List, Item
-    #
-    #     def after_save(record)
-    #       list = record.is_a?(List) ? record : record.list
-    #       expire_page(:controller => "lists", :action => %w( show public feed ), :id => list.id)
-    #       expire_action(:controller => "lists", :action => "all")
-    #       list.shares.each { |share| expire_page(:controller => "lists", :action => "show", :id => share.url_key) }
-    #     end
-    #   end
-    #
-    # The sweeper is assigned in the controllers that wish to have its job performed using the <tt>cache_sweeper</tt> class method:
-    #
-    #   class ListsController < ApplicationController
-    #     caches_action :index, :show, :public, :feed
-    #     cache_sweeper :list_sweeper, :only => [ :edit, :destroy, :share ]
-    #   end
-    #
-    # In the example above, four actions are cached and three actions are responsible for expiring those caches.
-    module Sweeping
-      def self.included(base) #:nodoc:
-        base.extend(ClassMethods)
-      end
-
-      module ClassMethods #:nodoc:
-        def cache_sweeper(*sweepers)
-          return unless perform_caching
-          configuration = sweepers.extract_options!
-          sweepers.each do |sweeper|
-            ActiveRecord::Base.observers << sweeper if defined?(ActiveRecord) and defined?(ActiveRecord::Base)
-            sweeper_instance = Object.const_get(Inflector.classify(sweeper)).instance
-
-            if sweeper_instance.is_a?(Sweeper)
-              around_filter(sweeper_instance, :only => configuration[:only])
-            else
-              after_filter(sweeper_instance, :only => configuration[:only])
-            end
-          end
-        end
-      end
-    end
-
-    if defined?(ActiveRecord) and defined?(ActiveRecord::Observer)
-      class Sweeper < ActiveRecord::Observer #:nodoc:
-        attr_accessor :controller
-
-        def before(controller)
-          self.controller = controller
-          callback(:before)
-        end
-
-        def after(controller)
-          callback(:after)
-          # Clean up, so that the controller can be collected after this request
-          self.controller = nil
-        end
-
-        protected
-          # gets the action cache path for the given options.
-          def action_path_for(options)
-            ActionController::Caching::Actions::ActionCachePath.path_for(controller, options)
-          end
-
-          # Retrieve instance variables set in the controller.
-          def assigns(key)
-            controller.instance_variable_get("@#{key}")
-          end
-
-        private
-          def callback(timing)
-            controller_callback_method_name = "#{timing}_#{controller.controller_name.underscore}"
-            action_callback_method_name     = "#{controller_callback_method_name}_#{controller.action_name}"
-
-            send!(controller_callback_method_name) if respond_to?(controller_callback_method_name, true)
-            send!(action_callback_method_name)     if respond_to?(action_callback_method_name, true)
-          end
-
-          def method_missing(method, *arguments)
-            return if @controller.nil?
-            @controller.send!(method, *arguments)
-          end
-      end
-    end
-
-    module SqlCache
-      def self.included(base) #:nodoc:
-        if defined?(ActiveRecord) && ActiveRecord::Base.respond_to?(:cache)
-          base.alias_method_chain :perform_action, :caching
-        end
-      end
-
-      def perform_action_with_caching
-        ActiveRecord::Base.cache do
-          perform_action_without_caching
-        end
-      end
-    end
   end
-end
+end
\ No newline at end of file