--- /dev/null
+require 'set'
+
+module ActionController #:nodoc:
+ module Caching
+ # 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 :index, :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.
+ #
+ # And you can also use :if (or :unless) to pass a Proc that specifies when the action should be cached.
+ #
+ # Finally, if you are using memcached, you can also pass :expires_in.
+ #
+ # class ListsController < ApplicationController
+ # before_filter :authenticate, :except => :public
+ # caches_page :public
+ # caches_action :index, :if => Proc.new { |c| !c.request.format.json? } # cache if is not a JSON request
+ # caches_action :show, :cache_path => { :project => 1 }, :expires_in => 1.hour
+ # caches_action :feed, :cache_path => Proc.new { |controller|
+ # controller.params[:user_id] ?
+ # controller.send(:user_list_url, controller.params[:user_id], controller.params[:id]) :
+ # controller.send(:list_url, controller.params[:id]) }
+ # end
+ #
+ # If you pass :layout => false, it will only cache your action content. It is useful when your layout has dynamic information.
+ #
+ module Actions
+ def self.included(base) #:nodoc:
+ base.extend(ClassMethods)
+ base.class_eval do
+ attr_accessor :rendered_action_cache, :action_cache_path
+ end
+ end
+
+ module ClassMethods
+ # Declares that +actions+ should be cached.
+ # See ActionController::Caching::Actions for details.
+ def caches_action(*actions)
+ return unless cache_configured?
+ options = actions.extract_options!
+ filter_options = { :only => actions, :if => options.delete(:if), :unless => options.delete(:unless) }
+
+ cache_filter = ActionCacheFilter.new(:layout => options.delete(:layout), :cache_path => options.delete(:cache_path), :store_options => options)
+ around_filter(cache_filter, filter_options)
+ end
+ end
+
+ protected
+ def expire_action(options = {})
+ return unless cache_configured?
+
+ if options[:action].is_a?(Array)
+ options[:action].dup.each do |action|
+ expire_fragment(ActionCachePath.path_for(self, options.merge({ :action => action }), false))
+ end
+ else
+ expire_fragment(ActionCachePath.path_for(self, options, false))
+ end
+ end
+
+ class ActionCacheFilter #:nodoc:
+ def initialize(options, &block)
+ @options = options
+ end
+
+ def before(controller)
+ cache_path = ActionCachePath.new(controller, path_options_for(controller, @options.slice(:cache_path)))
+ if cache = controller.read_fragment(cache_path.path, @options[:store_options])
+ controller.rendered_action_cache = true
+ set_content_type!(controller, cache_path.extension)
+ options = { :text => cache }
+ options.merge!(:layout => true) if cache_layout?
+ controller.__send__(:render, options)
+ false
+ else
+ controller.action_cache_path = cache_path
+ end
+ end
+
+ def after(controller)
+ return if controller.rendered_action_cache || !caching_allowed(controller)
+ action_content = cache_layout? ? content_for_layout(controller) : controller.response.body
+ controller.write_fragment(controller.action_cache_path.path, action_content, @options[:store_options])
+ 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
+
+ def cache_layout?
+ @options[:layout] == false
+ end
+
+ def content_for_layout(controller)
+ controller.response.layout && controller.response.template.instance_variable_get('@cached_content_for_layout')
+ end
+ end
+
+ class ActionCachePath
+ attr_reader :path, :extension
+
+ class << self
+ def path_for(controller, options, infer_extension=true)
+ new(controller, options, infer_extension).path
+ end
+ end
+
+ # When true, infer_extension will look up the cache path extension from the request's path & format.
+ # This is desirable when reading and writing the cache, but not when expiring the cache - expire_action should expire the same files regardless of the request format.
+ def initialize(controller, options = {}, infer_extension=true)
+ if infer_extension and options.is_a? Hash
+ request_extension = extract_extension(controller.request)
+ options = options.reverse_merge(:format => request_extension)
+ end
+ path = controller.url_for(options).split('://').last
+ normalize!(path)
+ if infer_extension
+ @extension = request_extension
+ add_extension!(path, @extension)
+ end
+ @path = URI.unescape(path)
+ end
+
+ private
+ def normalize!(path)
+ path << 'index' if path[-1] == ?/
+ end
+
+ def add_extension!(path, extension)
+ path << ".#{extension}" if extension and !path.ends_with?(extension)
+ end
+
+ def extract_extension(request)
+ # Don't want just what comes after the last '.' to accommodate multi part extensions
+ # such as tar.gz.
+ extension = request.path[/^[^.]+\.(.+)$/, 1]
+
+ # If there's no extension in the path, check request.format
+ if extension.nil?
+ extension = request.cache_format
+ end
+ extension
+ end
+ end
+ end
+ end
+end
projects / depot.git / blobdiff