Action caching helpers

controller.rb

caches_action :index, :cache_path => Proc.new {
  cache_key_for_relation(current_user.received_deliveries)
}

def cache_key_for_relation(relation, order_clause)
    relation = relation.reorder(order_clause)
    count = relation.count

    if count > 0
      cache_key_for "#{relation.first.cache_key}-#{count}"
    else
      cache_key_for empty_key
    end
end

def cache_key_for(key_name)
   "#{action_name}/#{key_name}"
end