https://nginxstore.com/blog/api-gateway/nginx-app-protect-waf%eb%a1%9c-%ec%a7%80%ec%97%b0%ec%8b%9c%ea%b0%84-%ec%b6%94%ea%b0%80-%ec%97%86%eb%8a%94-api-gateway-%eb%b3%b4%ed%98%b8/