nginx.conf

upstream puma {
  server unix:///home/ubuntu/apps/MyApp/shared/tmp/sockets/MyApp-puma.sock;
}

server {
  listen 80 default_server deferred;

  if ($http_user_agent ~* (banned|banned1|banned2)) {
    return 403;
  }

  if ($http_user_agent == "-") {
    return 403;
  }
  
  # server_name example.com;

  root /home/ubuntu/apps/MyApp/current/public;
  access_log /home/ubuntu/apps/MyApp/current/log/nginx.access.log;
  error_log /home/ubuntu/apps/MyApp/current/log/nginx.error.log info;

  location ^~ /public/ {
    autoindex on;
    alias /home/ubuntu/apps/MyApp/current/public/;
    gzip_static on;
    expires max;
    add_header Cache-Control public;
  }

  try_files $uri/index.html $uri @puma;
  location @puma {
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header Host $http_host;
    proxy_redirect off;

    proxy_pass http://puma;
  }

  error_page 500 502 503 504 /500.html;
  client_max_body_size 10M;
  keepalive_timeout 10;
}

wget.sh

$ wget http://example.com/path -O /dev/null --user-agent="banned" 
http://example.com/path
Connecting to example.com:80... connected.
HTTP request sent, awaiting response... 200 OK