How to use apigee with koala

facebook_config_initializer.rb

if ENV['APIGEE_FACEBOOK_API_ENDPOINT']
  Koala::Facebook.rest_server = ENV['APIGEE_FACEBOOK_API_ENDPOINT']
else
  # Get this value from Heroku.
  # Once you have enabled the addon, boot up the 'heroku console' and run the following:
  # puts ENV['APIGEE_FACEBOOK_API_ENDPOINT']
  Koala::Facebook.rest_server = "facebook-api-appXXXXXX.apigee.com"
end

module Facebook
  APP_ID = Settings.facebook.app_id
  SECRET = Settings.facebook.app_secret
end

Koala::Facebook::OAuth.class_eval do
  def initialize_with_default_settings(*args)
    case args.size
      when 0, 1
        raise "application id and/or secret are not specified in the config" unless Facebook::APP_ID && Facebook::SECRET
        initialize_without_default_settings(Facebook::APP_ID.to_s, Facebook::SECRET.to_s, args.first)
      when 2, 3
        initialize_without_default_settings(*args)
    end
  end

  alias_method_chain :initialize, :default_settings
end  

Gemfile

# facebook library for Ruby, supporting the Graph API (including the batch requests and photo uploads), the REST API, realtime updates, test users, and OAuth validation

gem 'koala', :git => 'git@github.com:jaigouk/koala.git'  

testing_koala.rake

require 'koala'

namespace :koala do

  desc "testing koala with apigee"

  task :dance => :environment do

    # step1. change graph server to apigee
    Koala::Facebook.rest_server= "facebook-api-appXXXXXX.apigee.com"
    puts "_______________"
    puts Koala::Facebook.rest_server

    # step2. oauth
    app_id = "my_id"
    app_secret = "secret"
    callback_url = "http://callback.com"
    oauth = Koala::Facebook::OAuth.new(app_id, app_secret, callback_url)
    oauth_access_token = oauth.get_app_access_token

    graph = Koala::Facebook::API.new(oauth_access_token)
    puts graph.search("koala")

  end
end