Nginx proxy pass to localhost:3000 for development

nginx.conf

worker_processes  1;

error_log  /usr/local/var/log/nginx.error.log;

events {
    worker_connections  1024;
}

http {
    include            mime.types;
    default_type       application/octet-stream;
    sendfile           on;
    keepalive_timeout  65;

    upstream dev {
      server 127.0.0.1:3000;
    }
    
    server {
      listen       80;
      
      # You could put a server_name directive here (or multiple) if
      # you have not setup wildcard DNS for *.dev domains
      # See http://jessedearing.com/nodes/9-setting-up-wildcard-subdomains-on-os-x-10-6

      # If we choose a root, then we can't switch things around easily
      # Using /dev/null means that static assets are served through
      # Rails instead, which for development is okay
      root         /dev/null;

      index        index.html index.htm;
 
      try_files  $uri/index.html $uri.html $uri @dev;
 
      location @dev {
        proxy_set_header  X-Real-IP        $remote_addr;
        proxy_set_header  X-Forwarded-For  $proxy_add_x_forwarded_for;
        proxy_set_header  Host             $http_host;
        proxy_redirect    off;
        proxy_pass        http://dev;
      }
      error_page   500 502 503 504  /50x.html;
    }            
}