Integrate AMo JSON serializer into AR

1 files changed, 69 insertions, 4 deletions

diff --git a/activemodel/lib/active_model/serializers/json.rb b/activemodel/lib/active_model/serializers/json.rb
index 0636e8c330..adf200597d 100644
--- a/activemodel/lib/active_model/serializers/json.rb
+++ b/activemodel/lib/active_model/serializers/json.rb
@@ -16,10 +16,9 @@ module ActiveModel
       class Serializer < ActiveModel::Serializer
         def serializable_hash
           model = super
-          if @serializable.include_root_in_json
-            model = { @serializable.class.model_name.element => model }
-          end
-          model
+          @serializable.include_root_in_json ?
+            { @serializable.class.model_name.element => model } :
+            model
         end
 
         def serialize
@@ -27,6 +26,72 @@ module ActiveModel
         end
       end
 
+      # Returns a JSON string representing the model. Some configuration is
+      # available through +options+.
+      #
+      # The option <tt>ActiveRecord::Base.include_root_in_json</tt> controls the
+      # top-level behavior of to_json. In a new Rails application, it is set to 
+      # <tt>true</tt> in initializers/new_rails_defaults.rb. When it is <tt>true</tt>,
+      # to_json will emit a single root node named after the object's type. For example:
+      #
+      #   konata = User.find(1)
+      #   ActiveRecord::Base.include_root_in_json = true
+      #   konata.to_json
+      #   # => { "user": {"id": 1, "name": "Konata Izumi", "age": 16,
+      #                   "created_at": "2006/08/01", "awesome": true} }
+      #
+      #   ActiveRecord::Base.include_root_in_json = false
+      #   konata.to_json
+      #   # => {"id": 1, "name": "Konata Izumi", "age": 16,
+      #         "created_at": "2006/08/01", "awesome": true}
+      #
+      # The remainder of the examples in this section assume include_root_in_json is set to
+      # <tt>false</tt>.
+      #
+      # Without any +options+, the returned JSON string will include all
+      # the model's attributes. For example:
+      #
+      #   konata = User.find(1)
+      #   konata.to_json
+      #   # => {"id": 1, "name": "Konata Izumi", "age": 16,
+      #         "created_at": "2006/08/01", "awesome": true}
+      #
+      # The <tt>:only</tt> and <tt>:except</tt> options can be used to limit the attributes
+      # included, and work similar to the +attributes+ method. For example:
+      #
+      #   konata.to_json(:only => [ :id, :name ])
+      #   # => {"id": 1, "name": "Konata Izumi"}
+      #
+      #   konata.to_json(:except => [ :id, :created_at, :age ])
+      #   # => {"name": "Konata Izumi", "awesome": true}
+      #
+      # To include any methods on the model, use <tt>:methods</tt>.
+      #
+      #   konata.to_json(:methods => :permalink)
+      #   # => {"id": 1, "name": "Konata Izumi", "age": 16,
+      #         "created_at": "2006/08/01", "awesome": true,
+      #         "permalink": "1-konata-izumi"}
+      #
+      # To include associations, use <tt>:include</tt>.
+      #
+      #   konata.to_json(:include => :posts)
+      #   # => {"id": 1, "name": "Konata Izumi", "age": 16,
+      #         "created_at": "2006/08/01", "awesome": true,
+      #         "posts": [{"id": 1, "author_id": 1, "title": "Welcome to the weblog"},
+      #                   {"id": 2, author_id: 1, "title": "So I was thinking"}]}
+      #
+      # 2nd level and higher order associations work as well:
+      #
+      #   konata.to_json(:include => { :posts => {
+      #                                  :include => { :comments => {
+      #                                                :only => :body } },
+      #                                  :only => :title } })
+      #   # => {"id": 1, "name": "Konata Izumi", "age": 16,
+      #         "created_at": "2006/08/01", "awesome": true,
+      #         "posts": [{"comments": [{"body": "1st post!"}, {"body": "Second!"}],
+      #                    "title": "Welcome to the weblog"},
+      #                   {"comments": [{"body": "Don't think too hard"}],
+      #                    "title": "So I was thinking"}]}
       def encode_json(encoder)
         Serializer.new(self, encoder.options).to_s
       end