discourse/app/jobs/regular/notify_moved_posts.rb

module Jobs

  class NotifyMovedPosts < Jobs::Base

    def execute(args)
      raise Discourse::InvalidParameters.new(:post_ids) if args[:post_ids].blank?
      raise Discourse::InvalidParameters.new(:moved_by_id) if args[:moved_by_id].blank?

      # Make sure we don't notify the same user twice (in case multiple posts were moved at once.)
      users_notified = Set.new
      posts = Post.where(id: args[:post_ids]).where('user_id <> ?', args[:moved_by_id]).includes(:user, :topic)
      if posts.present?
        moved_by = User.find_by(id: args[:moved_by_id])

        posts.each do |p|
          unless users_notified.include?(p.user_id)
            p.user.notifications.create(notification_type: Notification.types[:moved_post],
                                        topic_id: p.topic_id,
                                        post_number: p.post_number,
                                        data: { topic_title: p.topic.title,
                                                display_username: moved_by.username }.to_json)
            users_notified << p.user_id
          end
        end
      end

    end

  end

end