nginx.conf

location … {
  if ($http_x_real_ip != ''){
    set $clientip $http_x_real_ip;
    break;
  }  
  if ($http_x_real_ip = ''){
    set $clientip $remote_addr;
    break;
  }
  proxy_set_header X-Real-IP $clientip;
}

location ^~ /api/stomp {
  proxy_pass http://tomcat:8080;
  proxy_http_version 1.1;
  proxy_set_header Upgrade "websocket";
  proxy_set_header Connection "upgrade";
  proxy_set_header Host $host;
}