xml_renderer.rb

# test

require File.dirname(__FILE__) + '/../test_helper'

class XMLRendererTest < ActiveSupport::TestCase
  context "A class with XMLRenderer mixed in" do
    setup do
      class ::DummyClass
        include XMLRenderer
      end
      @dummy = DummyClass.new
    end

    should "respond to to_show_xml" do
      assert_respond_to @dummy, :to_show_xml
    end

    should "respond to views_show_xml" do
      assert_respond_to @dummy, :views_show_xml
    end

    should "respond to default_url_options on the class" do
      assert_respond_to DummyClass, :default_url_options
    end

    should "contain the host from APP_URL_PREFIX in the default url options" do
      assert_equal URI.parse(APP_URL_PREFIX).host, DummyClass.default_url_options[:host]
    end

    should "have ERB::Util as an ancestor" do
      assert DummyClass.ancestors.include?( ERB::Util )
    end

    should "have ActionController::UrlWriter as an ancestor" do
      assert DummyClass.ancestors.include?( ActionController::UrlWriter )
    end

    should "have ActionView::Helpers::UrlHelper as an ancestor" do
      assert DummyClass.ancestors.include?( ActionView::Helpers::UrlHelper )
    end

    should "return the expected file path when sent #views_show_xml" do
      assert_equal File.expand_path(File.join(RAILS_ROOT, "app", "views", "dummy_classes", "show.xml.builder")),
                   @dummy.views_show_xml
    end

    should "load the right file and eval it when sent #to_show_xml" do
      xml_mock = mock
      xml_mock.expects(:test_method)
      @dummy.expects(:views_show_xml).returns("views_show_xml")
      IO.expects(:read).with("views_show_xml").returns("xml.test_method")
      Builder::XmlMarkup.expects(:new).with(:target => "").returns(xml_mock)

      @dummy.to_show_xml
    end
    
  end
  
end

# lib

module XMLRenderer

  include ERB::Util
  include ActionView::Helpers::UrlHelper
  include ActionController::UrlWriter

  def self.included(base)
    base.extend(ClassMethods)
  end

  module ClassMethods
    def default_url_options
      { :host => URI.parse(APP_URL_PREFIX).host }
    end
  end

  def to_show_xml
    output = ""
    xml = Builder::XmlMarkup.new(:target => output)
    @page = self
    eval(IO.read( views_show_xml ))
    output
  end

  def views_show_xml
    File.expand_path( File.join( RAILS_ROOT,
                                 "app",
                                 "views",
                                 self.class.name.underscore.pluralize,
                                 "show.xml.builder" ))
  end
  
end