require 'thread_safe' require 'action_view/dependency_tracker' module ActionView class Digestor cattr_reader(:cache) @@cache = ThreadSafe::Cache.new def self.digest(name, format, finder, options = {}) cache_key = ([name, format] + Array.wrap(options[:dependencies])).join('.') @@cache.fetch(cache_key) do @@cache[cache_key] ||= nil if options[:partial] # Prevent re-entry klass = options[:partial] || name.include?("/_") ? PartialDigestor : Digestor digest = klass.new(name, format, finder, options).digest @@cache[cache_key] = digest # Store the value end end attr_reader :name, :format, :finder, :options def initialize(name, format, finder, options={}) @name, @format, @finder, @options = name, format, finder, options end def digest Digest::MD5.hexdigest("#{source}-#{dependency_digest}").tap do |digest| logger.try :info, "Cache digest for #{name}.#{format}: #{digest}" end rescue ActionView::MissingTemplate logger.try :error, "Couldn't find template for digesting: #{name}.#{format}" '' end def dependencies DependencyTracker.find_dependencies(name, template) rescue ActionView::MissingTemplate [] # File doesn't exist, so no dependencies end def nested_dependencies dependencies.collect do |dependency| dependencies = PartialDigestor.new(dependency, format, finder).nested_dependencies dependencies.any? ? { dependency => dependencies } : dependency end end private def logger ActionView::Base.logger end def logical_name name.gsub(%r|/_|, "/") end def partial? false end def template @template ||= finder.find(logical_name, [], partial?, formats: [ format ]) end def source template.source end def dependency_digest template_digests = dependencies.collect do |template_name| Digestor.digest(template_name, format, finder, partial: true) end (template_digests + injected_dependencies).join("-") end def injected_dependencies Array.wrap(options[:dependencies]) end end class PartialDigestor < Digestor # :nodoc: def partial? true end end end