code: func validateKiteKey(k *protocol.Kite) error {
  	fields := k.Query().Fields()
  
  	// Validate fields.
  	for k, v := range fields {
  		if v == "" {
  			return fmt.Errorf("Empty Kite field: %s", k)
  		}
  		if strings.ContainsRune(v, '/') {
  			return fmt.Errorf("Field \"%s\" must not contain '/'", k)
  		}
  	}
  
  	return nil
  }
docs: // validateKiteKey returns a string representing the kite uniquely
  // that is suitable to use as a key for etcd.