proxy_set_header Host              $host;
proxy_set_header X-Forwarded-Host  $host;
proxy_set_header X-Forwarded-For   $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Real-IP         $remote_addr;
proxy_set_header X-WAF-URL-FLAG    $scheme://$host:$server_port;