FriendlyId Ruby on Rails gem – update (refresh) slug after each record change

If you want to have slugs that are refreshed (updated) each time you change corresponding field in your ActiveRecord models, put this at the end of your initializers/friendly_id.rb file:

module FriendlyId
  module Slugged
    def should_generate_new_friendly_id?
      return true if send(friendly_id_config.slug_column).nil? && !send(friendly_id_config.base).nil?

      change = :"#{friendly_id_config.base}_changed?"
      return true if respond_to?(change) && send(change)

      false
    end
  end
end

This will update slug each time related column (friendly_id_config.base) has changed. Keep in mind, that this method won't work if you use non-column slug method as a base for friendly ids, since it uses ActiveRecord::Dirty interface.