--- /dev/null
+require 'fileutils'
+require 'uri'
+
+module ActionController #:nodoc:
+ module Caching
+ # 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 Action Pack. This is the fastest way to cache your content as opposed to going dynamically
+ # through the process of 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_page</tt> class method:
+ #
+ # class WeblogController < ActionController::Base
+ # caches_page :show, :new
+ # end
+ #
+ # This will generate cache files such as <tt>weblog/show/5.html</tt> and <tt>weblog/new.html</tt>,
+ # 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 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 <tt>Base.page_cache_directory = "/document/root"</tt>.
+ # For Rails, this directory has already been set to Rails.public_path (which is usually set to <tt>RAILS_ROOT + "/public"</tt>). Changing
+ # this setting can be useful to avoid naming conflicts with files in <tt>public/</tt>, but doing so will likely require configuring your
+ # web server to look in the new location for cached files.
+ #
+ # == Setting the cache extension
+ #
+ # Most Rails requests do not have an extension, such as <tt>/weblog/new</tt>. In these cases, the page caching mechanism will add one in
+ # order to make it easy for the cached files to be picked up properly by the web server. By default, this cache extension is <tt>.html</tt>.
+ # If you want something else, like <tt>.php</tt> or <tt>.shtml</tt>, just set Base.page_cache_extension. In cases where a request already has an
+ # extension, such as <tt>.xml</tt> or <tt>.rss</tt>, page caching will not add an extension. This allows it to work well with RESTful apps.
+ module Pages
+ def self.included(base) #:nodoc:
+ base.extend(ClassMethods)
+ base.class_eval do
+ @@page_cache_directory = defined?(Rails.public_path) ? Rails.public_path : ""
+ 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.
+ #
+ # Usage:
+ #
+ # # cache the index action
+ # caches_page :index
+ #
+ # # cache the index action except for JSON requests
+ # caches_page :index, :if => Proc.new { |c| !c.request.format.json? }
+ def caches_page(*actions)
+ return unless perform_caching
+ options = actions.extract_options!
+ after_filter({:only => actions}.merge(options)) { |c| c.cache_page }
+ 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
+ end
+end
\ No newline at end of file
projects / depot.git / blobdiff