auth/token.go
func ParseToken(header string) (string, error) {
	s := strings.Split(header, " ")
	var value string
	if len(s) < 3 {
		value = s[len(s)-1]
	}
	if value != "" {
		return value, nil
	}
	return value, ErrInvalidToken
}
func ParseToken(header string) (string, error) {
	s := strings.Split(header, " ")
	var value string
	if len(s) < 3 {
		value = s[len(s)-1]
	}
	if value != "" {
		return value, nil
	}
	return value, ErrInvalidToken
}
// ParseToken extracts token from a header:
// 'type token' or 'token'