update plugins to allow listing via API

app/models/plugin.rb

@@ -18,6 +18,44 @@ class Plugin < ActiveRecord::Base
   has_many :windows, -> { where window_type: 'plugin' }, :foreign_key => :content_id, :source => :window
   before_destroy { |record| record.windows.each { |window| window.delete } }
 
+  # pagination variables
+  cattr_reader :per_page
+  @@per_page = 15
+
+  # paginated hash for json and xml output
+  # plugins input must be paginated
+  def self.paginated_hash(plugins)
+    {
+      pagination:
+      {
+        current_page: plugins.current_page,
+        per_page: plugins.per_page,
+        total_entries: plugins.total_entries,
+      },
+      plugins: plugins.as_json(Plugin.public_options)
+    }
+  end
+
+  # for to_json or to_xml, return only the public attributes
+  def self.public_options
+    {
+      :root => false,
+      :only => [:id, :name, :created_at, :public_flag],
+      :methods => [:username, :url]
+    }
+  end
+
+  # login name of the user who created the plugin
+  def username; self.user.try(:login); end
+
+  # url for the plugin
+  def url
+    domain = 'https://thingspeak.com'
+    domain = 'http://staging.thingspeak.com' if Rails.env.staging?
+    domain = 'http://127.0.0.1:3000' if Rails.env.development?
+    return "#{domain}/plugins/#{self.id}"
+  end
+
   def destroy_window
     window_id = Window.where(content_id: self.id, window_type: 'plugin').first.id
     Window.delete(window_id)