@GetMapping("/properties")
    public String properties() {
        Properties properties = new Properties();
        try {
            InputStreamReader inputStreamReader = new InputStreamReader(Objects.requireNonNull(this.getClass().getClassLoader().getResourceAsStream("application.properties")), StandardCharsets.UTF_8);
            properties.load(inputStreamReader);
            return properties.getProperty("app.id");
        } catch (IOException e1) {
            e1.printStackTrace();
        }
        return "";
    }