ewoodh2o/Gemfile

## app-controllers-facebook_tab_controller.rb
class FacebookTabController < ApplicationController

  ssl_allowed :show, :channel

  before_filter :load_auth, :except => [ :channel ]

  def show
    render is_fan? ? 'coupon' : 'like_gate'
  end

  ## Facebook Channel File
  ## Assists with cross-site XHR and IFRAME issues
  def channel
    headers['Pragma'] = 'public'
    headers['Cache-Control'] = "max-age=#{10*365*24*60*60}"
    headers['Expires'] = 10.years.from_now.utc.to_s(:rfc1123)
    render :text => "<script src=\"//connect.facebook.net/en_US/all.js\"></script>"
  end

  #################################################
  ## Facebook Helpers
  #################################################

  def facebook_tab_config
    @@_fb_tab_config ||= YAML.load(File.open(File.join(Rails.root, 'config', 'facebook_tab.yml')))
    if Rails.env.development?
      if request.host.include?('elliott')
        @@_fb_tab_config['dev-elliott'].symbolize_keys
      end
    else
      @@_fb_tab_config[Rails.env].symbolize_keys
    end
  end
  helper_method :facebook_tab_config

  def is_fan?
    return false unless @auth.present?
    @auth.data['page']['liked']
  end
  helper_method :is_fan?

  ##################################################
  ## FB Authorization Filter
  ##################################################

  private

    def load_auth
      return unless params[:signed_request].present?
      @auth = FbGraph::Auth.new(facebook_tab_config[:app_id], facebook_tab_config[:app_secret])
      @auth.from_signed_request(params[:signed_request])
    end

end

## app-views-facebook_tab-_marketing.html.erb
<!-- You can put your main landing page content here. -->

## app-views-facebook_tab-coupon.html.erb
<div id="coupon">
  <div id="deal">
    <div class="amount">10% Off</div>
    <div class="sub">Your next purchase</div>
    <div class="details">Coupon Code: <span class="code">fblike2012</span></div>
  </div>
  <a id="redeem" href="http://<%= facebook_tab_config[:domain] %>/?from=facebook_coupon" target="_top">Redeem</a>
</div>

<%= render :partial => 'marketing' %>

## app-views-facebook_tab-like_gate.html.erb
<div id="call-to-action">Like us to receive a free coupon!</div>

<%= render :partial => 'marketing' %>

## app-views-layouts-facebook_tab.html.erb
<!DOCTYPE html>
<html>
<head>
  <title>Your Like-Gate Coupon on Facebook</title>
  <%= stylesheet_link_tag 'facebook_tab' %>
</head>
<body>

  <%= yield %>

  <div id="fb-root"></div>
  <script>
    window.fbAsyncInit = function() {
      FB.init({
        appId      : '<%= facebook_tab_config[:app_id] %>', // App ID
        channelURL : '//<%= facebook_tab_config[:domain] %>/facebook-tab/channel.html', // Channel File
        status     : true, // check login status
        cookie     : true, // enable cookies to allow the server to access the session
        oauth      : true, // enable OAuth 2.0
        xfbml      : true  // parse XFBML
      });

      FB.Canvas.setAutoGrow();
    };

    // Load the SDK Asynchronously
    (function(d){
       var js, id = 'facebook-jssdk'; if (d.getElementById(id)) {return;}
       js = d.createElement('script'); js.id = id; js.async = true;
       js.src = "//connect.facebook.net/en_US/all.js";
       d.getElementsByTagName('head')[0].appendChild(js);
     }(document));
  </script>

</body>
</html>

## config-facebook_tab.yml
dev-elliott:
  app_id: '123456'
  app_secret: 'abcdef'
  domain: app.elliott.pipe.example.com

staging:
  app_id: '123456'
  app_secret: 'abcdef'
  domain: www.app.com

production:
  app_id: '123456'
  app_secret: 'abcdef'
  domain: www.app.com

## config-routes.rb
YourApplication::Application.routes.draw do

  match 'facebook-tab', :to => 'facebook_tab#show', :via => [ :get, :post ]
  match 'facebook-tab/channel', :to => 'facebook_tab#channel', :via => [ :get, :post ]

  # ... rest of your routes

end

## Gemfile
source 'http://rubygems.org'

gem 'rails', '3.0.10'

# ... include whatever you need, but the following is pertinent
gem 'fb_graph'
	class FacebookTabController < ApplicationController

	ssl_allowed :show, :channel

	before_filter :load_auth, :except => [ :channel ]

	def show
	render is_fan? ? 'coupon' : 'like_gate'
	end

	## Facebook Channel File
	## Assists with cross-site XHR and IFRAME issues
	def channel
	headers['Pragma'] = 'public'
	headers['Cache-Control'] = "max-age=#{10365246060}"
	headers['Expires'] = 10.years.from_now.utc.to_s(:rfc1123)
	render :text => "<script src=\"//connect.facebook.net/en_US/all.js\"></script>"
	end

	#################################################
	## Facebook Helpers
	#################################################

	def facebook_tab_config
	@@_fb_tab_config \|\|= YAML.load(File.open(File.join(Rails.root, 'config', 'facebook_tab.yml')))
	if Rails.env.development?
	if request.host.include?('elliott')
	@@_fb_tab_config['dev-elliott'].symbolize_keys
	end
	else
	@@_fb_tab_config[Rails.env].symbolize_keys
	end
	end
	helper_method :facebook_tab_config

	def is_fan?
	return false unless @auth.present?
	@auth.data['page']['liked']
	end
	helper_method :is_fan?

	##################################################
	## FB Authorization Filter
	##################################################

	private

	def load_auth
	return unless params[:signed_request].present?
	@auth = FbGraph::Auth.new(facebook_tab_config[:app_id], facebook_tab_config[:app_secret])
	@auth.from_signed_request(params[:signed_request])
	end

	end
	<div id="coupon">
	<div id="deal">
	<div class="amount">10% Off</div>
	<div class="sub">Your next purchase</div>
	<div class="details">Coupon Code: <span class="code">fblike2012</span></div>
	</div>
	<a id="redeem" href="http://<%= facebook_tab_config[:domain] %>/?from=facebook_coupon" target="_top">Redeem</a>
	</div>

	<%= render :partial => 'marketing' %>
	<div id="call-to-action">Like us to receive a free coupon!</div>

	<%= render :partial => 'marketing' %>
	<!DOCTYPE html>
	<html>
	<head>
	<title>Your Like-Gate Coupon on Facebook</title>
	<%= stylesheet_link_tag 'facebook_tab' %>
	</head>
	<body>

	<%= yield %>

	<div id="fb-root"></div>
	<script>
	window.fbAsyncInit = function() {
	FB.init({
	appId : '<%= facebook_tab_config[:app_id] %>', // App ID
	channelURL : '//<%= facebook_tab_config[:domain] %>/facebook-tab/channel.html', // Channel File
	status : true, // check login status
	cookie : true, // enable cookies to allow the server to access the session
	oauth : true, // enable OAuth 2.0
	xfbml : true // parse XFBML
	});

	FB.Canvas.setAutoGrow();
	};

	// Load the SDK Asynchronously
	(function(d){
	var js, id = 'facebook-jssdk'; if (d.getElementById(id)) {return;}
	js = d.createElement('script'); js.id = id; js.async = true;
	js.src = "//connect.facebook.net/en_US/all.js";
	d.getElementsByTagName('head')[0].appendChild(js);
	}(document));
	</script>

	</body>
	</html>
	dev-elliott:
	app_id: '123456'
	app_secret: 'abcdef'
	domain: app.elliott.pipe.example.com

	staging:
	app_id: '123456'
	app_secret: 'abcdef'
	domain: www.app.com

	production:
	app_id: '123456'
	app_secret: 'abcdef'
	domain: www.app.com
	YourApplication::Application.routes.draw do

	match 'facebook-tab', :to => 'facebook_tab#show', :via => [ :get, :post ]
	match 'facebook-tab/channel', :to => 'facebook_tab#channel', :via => [ :get, :post ]

	# ... rest of your routes

	end
	source 'http://rubygems.org'

	gem 'rails', '3.0.10'

	# ... include whatever you need, but the following is pertinent
	gem 'fb_graph'