expand_cache_key

# File activesupport/lib/active_support/cache.rb, line 77
      def expand_cache_key(key, namespace = nil)
        expanded_cache_key = namespace ? "#{namespace}/" : ""

        prefix = ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]
        if prefix
          expanded_cache_key << "#{prefix}/"
        end

        expanded_cache_key << retrieve_cache_key(key)
        expanded_cache_key
      end