auth/jwt.go
func Token(r *http.Request) string {
	if token, ok := r.Context().Value(TokenKey).(string); ok {
		return token
	}

	return ""
}
func Token(r *http.Request) string {
	if token, ok := r.Context().Value(TokenKey).(string); ok {
		return token
	}

	return ""
}
// Token returns the token string stored in the request context, or an empty
// string.