app.somename.local无法正常工作，但是本地主机是app：3000的代理。我想通过在浏览器中输入app来访问server_name

worker_processes 1;

events {
  worker_connections 1024;
}

http {
  upstream app {
    server app:3000;
  }

  server {
    server_name app.somename.local;  

    location / {
      proxy_pass http://app/;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header HOST $http_host;
    }
  }
}