Add URL to serializers (closes rails-api#61)

Thanks so much to @vanstee for the initial
implementation!

lib/action_controller/serialization.rb

@@ -49,6 +49,7 @@ def _render_option_json(json, options)
 
       if serializer
         options[:scope] = serialization_scope
+        options[:url_options] = url_options
         json = serializer.new(json, options.merge(default_serializer_options || {}))
       end
       super

lib/active_model/serializer.rb

@@ -380,6 +380,10 @@ def initialize(object, options={})
       @object, @options = object, options
     end
 
+    def url_options
+      @options[:url_options]
+    end
+
     # Returns a json representation of the serializable
     # object including the root.
     def as_json(options=nil)

lib/active_model_serializers.rb

@@ -10,6 +10,12 @@ class Railtie < Rails::Railtie
         Rails::Generators.configure!(app.config.generators)
         require "generators/resource_override"
       end
+
+      initializer "include_routes.active_model_serializer" do |app|
+        ActiveSupport.on_load(:active_model_serializers) do
+          include app.routes.url_helpers
+        end
+      end
     end
   end
 end

test/serialization_test.rb

@@ -54,6 +54,18 @@ def as_json(*)
     end
   end
 
+  class HypermediaSerializable
+    def active_model_serializer
+      HypermediaSerializer
+    end
+  end
+
+  class HypermediaSerializer < ActiveModel::Serializer
+    def as_json(*)
+      { :link => hypermedia_url }
+    end
+  end
+
   class TestController < ActionController::Base
     protect_from_forgery
 
@@ -124,6 +136,10 @@ def render_json_with_custom_serializer
       render :json => [], :serializer => CustomSerializer
     end
 
+    def render_json_with_links
+      render :json => HypermediaSerializable.new
+    end
+
   private
     def default_serializer_options
       if params[:check_defaults]
@@ -229,4 +245,9 @@ def test_render_json_with_custom_serializer
     get :render_json_with_custom_serializer
     assert_match '{"hello":true}', @response.body
   end
+
+  def test_render_json_with_links
+    get :render_json_with_links
+    assert_match '{"link":"http://www.nextangle.com/hypermedia"}', @response.body
+  end
 end

test/serializer_test.rb

@@ -132,6 +132,12 @@ def test_serializer_receives_scope
     }, hash)
   end
 
+  def test_serializer_receives_url_options
+    user = User.new
+    user_serializer = UserSerializer.new(user, :url_options => { :host => "test.local" })
+    assert_equal({ :host => "test.local" }, user_serializer.url_options)
+  end
+
   def test_pretty_accessors
     user = User.new
     user.superuser = true

test/test_helper.rb

@@ -20,11 +20,13 @@
 module TestHelper
   Routes = ActionDispatch::Routing::RouteSet.new
   Routes.draw do
+    resource :hypermedia
     match ':controller(/:action(/:id))'
     match ':controller(/:action)'
   end
 
   ActionController::Base.send :include, Routes.url_helpers
+  ActiveModel::Serializer.send :include, Routes.url_helpers
 end
 
 ActiveSupport::TestCase.class_eval do