code: func IsValidPortName(port string) []string {
  	var errs []string
  	if len(port) > 15 {
  		errs = append(errs, MaxLenError(15))
  	}
  	if !portNameCharsetRegex.MatchString(port) {
  		errs = append(errs, "must contain only alpha-numeric characters (a-z, 0-9), and hyphens (-)")
  	}
  	if !portNameOneLetterRegexp.MatchString(port) {
  		errs = append(errs, "must contain at least one letter or number (a-z, 0-9)")
  	}
  	if strings.Contains(port, "--") {
  		errs = append(errs, "must not contain consecutive hyphens")
  	}
  	if len(port) > 0 && (port[0] == '-' || port[len(port)-1] == '-') {
  		errs = append(errs, "must not begin or end with a hyphen")
  	}
  	return errs
  }
docs: // IsValidPortName check that the argument is valid syntax. It must be
  // non-empty and no more than 15 characters long. It may contain only [-a-z0-9]
  // and must contain at least one letter [a-z]. It must not start or end with a
  // hyphen, nor contain adjacent hyphens.
  //
  // Note: We only allow lower-case characters, even though RFC 6335 is case
  // insensitive.