Added JSON support to user preferences

app/controllers/api/user_preferences_controller.rb

@@ -7,12 +7,17 @@ module Api
 
     around_action :api_call_handle_error
 
+    before_action :set_request_formats
+
     ##
     # return all the preferences as an XML document
     def index
       @user_preferences = current_user.preferences
 
-      render :formats => [:xml]
+      respond_to do |format|
+        format.xml
+        format.json
+      end
     end
 
     ##

app/views/api/user_preferences/_user_preference.json.jbuilder

@@ -0,0 +1,6 @@
+attrs = {
+  "k" => user_preference.k,
+  "v" => user_preference.v
+}
+
+json.preference(attrs)

app/views/api/user_preferences/index.json.jbuilder

@@ -0,0 +1 @@
+json.partial! @user_preferences