Making a dynamic collection representer

gistfile1.rb

module Api
  module V1

    module CollectionRepresenter
      include Roar::JSON::HAL

      # include Roar::Representer::Feature::Hypermedia

      #pagination
      def total_pages
        nil
      end


      def total_records
        count
      end

      #property :page_number, getter: lambda { |args| args[:page_number] <-- that's the parameters you pass in }

      def tcount
        count
      end

      def xlass
        represented.class.to_s.split(':')[0].constantize
      end

      def child_representer
        base_class=represented.class.to_s.split(':')[0]
        rep_class = 'Api::V1::' + base_class + 'Representer'
        rep_class #.constantize
      end

      def collection_name
        represented.class.to_s.underscore.split('/')[0].pluralize
      end

      property :tcount
      property :child_representer

      property :total_pages
      property :per_page, getter: lambda { |args| args[:per_page] }
      property :page_number, :as => 'page', getter: lambda { |args| args[:page] }
      property :total_records, getter: lambda { |args| args[:total] }

      options = {
          class: :xlass,
          extend: QuestionRepresenter,
          # HELP
          # I want to call a method child_representer to dynamically find the right collection item representer
          # this does not work and fails with no such method or error
          #
          embedded: true,
          #decorator_scope: true,
          as: "osdi:questions"
      }

      collection :all, options


      link :self do

        cname =represented.class.to_s.underscore.split('/')[0].pluralize
        send("api_v1_#{cname}_path",
              only_path: false)
      end


    end
  end
end