# File lib/fog/aws/signaturev4.rb, line 42
      def canonical_query_string(query)
        canonical_query_string = []
        for key in (query || {}).keys.sort_by {|k| k.to_s}
          component = "#{Fog::AWS.escape(key.to_s)}=#{Fog::AWS.escape(query[key].to_s)}"
          canonical_query_string << component
        end
        canonical_query_string.join("&")
      end