specify protocol for url helpers in action mailer

config/initializers/mailer_config.rb

@@ -4,7 +4,8 @@
 
 require File.join(Rails.root, 'lib/messagebus/mailer')
 Diaspora::Application.configure do
-  config.action_mailer.default_url_options = {:host => AppConfig[:pod_uri].authority }
+  config.action_mailer.default_url_options = {:protocol => AppConfig[:pod_uri].scheme,
+                                              :host => AppConfig[:pod_uri].authority }
 
   unless Rails.env == 'test' || AppConfig[:mailer_on] != true
     if AppConfig[:mailer_method] == 'messagebus'