nodecg.conf

<VirtualHost *:80>

  ServerName nodecg.example.com

  Redirect permanent / https://nodecg.example.com/
</VirtualHost>

<VirtualHost *:443>
  ServerName nodecg.example.com
  ServerAdmin hosting@example.com

  SSLEngine on
  SSLCertificateFile      /path/to/ssl/cert.crt
  SSLCertificateKeyFile   /path/to/ssl/cert.key

  # Any other stuff for Lets Encrypt etc. as needed

  RewriteEngine on

  RewriteCond %{QUERY_STRING} transport=polling       [NC]
  RewriteRule /(.*)           http://127.0.0.1:9200/$1 [P]

  RewriteCond ${HTTP:Upgrade} websocket [NC]
  RewriteRule .* "ws:/127.0.0.1:9200/$1" [P,L]
  
  ProxyPass / http://127.0.0.1:9200/
</VirtualHost>