class Item class Proxy include FragmentLocalization attr_reader :id attr_writer :item, :owned, :wanted delegate :description, :name, :nc?, :thumbnail_url, to: :item def initialize(id) @id = id @known_outputs = {method: {}, partial: {}} end def as_json(options={}) cache_method(:as_json, include_hanger_status: false).tap do |json| json[:owned] = owned? json[:wanted] = wanted? end end def cached?(type, name) # TODO: is there a way to cache nil? Right now we treat is as a miss. # We eagerly read the cache rather than just check if the value exists, # which will usually cut down on cache requests. @known_outputs[type][name] ||= Rails.cache.read(fragment_key(type, name)) !@known_outputs[type][name].nil? end def owned? @owned end def to_partial_path # HACK: could break without warning! Item._to_partial_path end def wanted? @wanted end private def cache_method(method_name, *args, &block) # Two layers of cache: a local copy, in case the method is called again, # and then the Rails cache, before we hit the actual method call. @known_outputs[method_name] ||= begin key = fragment_key(:method, method_name) Rails.cache.fetch(key) { item.send(method_name, *args) } end end def item @item ||= Item.find(@id) end def fragment_key(type, name) prefix = type == :partial ? 'views/' : '' base = localize_fragment_key("items/#{@id}##{name}", I18n.locale) prefix + base end end end