docs: public static Deferred<String> metricNameAsync(final TSDB tsdb, 
        final byte[] row) {
      if (row == null || row.length < 1) {
        throw new IllegalArgumentException("Row key cannot be null or empty");
      }
      if (row.length < Const.SALT_WIDTH() + tsdb.metrics.width()) {
        throw new IllegalArgumentException("Row key is too short"); 
      }
      final byte[] id = Arrays.copyOfRange(
          row, Const.SALT_WIDTH(), tsdb.metrics.width() + Const.SALT_WIDTH());
      return tsdb.metrics.getNameAsync(id);
    }