checking for relayable in the dispatcher and the receiver

lib/diaspora/relayable.rb

@@ -13,6 +13,10 @@ module Diaspora
         xml_attr :author_signature
       end
     end
+    
+    def relayable
+      true
+    end
 
     def parent_guid
       self.parent.guid

lib/postzord/dispatch.rb

@@ -22,7 +22,7 @@ class Postzord::Dispatch
     unless @subscribers == nil
       remote_people, local_people = @subscribers.partition{ |person| person.owner_id.nil? }
 
-      if @object.is_a?(Comment) && @sender.owns?(@object.post)
+      if @object.respond_to?(:relayable) && @sender.owns?(@object.parent)
         user_ids = [*local_people].map{|x| x.owner_id }
         local_users = User.where(:id => user_ids)
         self.notify_users(local_users)

lib/postzord/receiver.rb

@@ -49,9 +49,9 @@ module Postzord
     end
 
     def xml_author
-      if @object.is_a?(Comment)
+      if @object.respond_to?(:relayable)
         #if A and B are friends, and A sends B a comment from C, we delegate the validation to the owner of the post being commented on
-        xml_author = @user.owns?(@object.post) ? @object.diaspora_handle : @object.post.author.diaspora_handle
+        xml_author = @user.owns?(@object.parent) ? @object.diaspora_handle : @object.parent.author.diaspora_handle
         @author = Webfinger.new(@object.diaspora_handle).fetch
       else
         xml_author = @object.diaspora_handle
@@ -71,7 +71,7 @@ module Postzord
       end
 
       # abort if we haven't received the post to a comment
-      if @object.is_a?(Comment) && @object.post.nil?
+      if @object.respond_to?(:relayable) && @object.parent.nil?
         Rails.logger.info("event=receive status=abort reason='received a comment but no corresponding post' recipient=#{@user_person.diaspora_handle} sender=#{@sender.diaspora_handle} payload_type=#{@object.class})")
         return false
       end