fix callback URL to not contain GET params

facebook.gemspec

@@ -8,6 +8,7 @@ Gem::Specification.new do |gem|
   gem.add_dependency 'oauth2', '>= 0.0.6'
   gem.add_dependency 'yajl-ruby', '~> 0.7.5'
   gem.add_dependency 'rack', '~> 1.1.0'
+  gem.add_dependency 'addressable', '~> 2.1.2'
   # gem.add_development_dependency 'rspec', '~> 1.2.9'
 
   gem.summary = "REST library + Rack middleware for the Facebook Graph API"

lib/facebook.rb

@@ -1,6 +1,7 @@
 require 'oauth2'
 require 'yajl'
 require 'rack/request'
+require 'addressable/uri'
 
 module Facebook
   class Client
@@ -33,13 +34,14 @@ def initialize(client, options = {})
 
     def call(env)
       request = Request.new(env)
-      callback_url = request.url
+      callback_url = Addressable::URI.parse(request.url)
+      callback_url.query = nil
 
       if code = request[:code]
         access_token = @client.get_access_token(code, callback_url)
         request.session[:facebook_access_token] = access_token.token
         request.session[:facebook_user] = Yajl::Parser.parse(access_token.get('/me'))
-        redirect_to_return_path
+        redirect_to_return_path(request)
       else
         redirect @client.authorize_url(:redirect_uri => callback_url)
       end