HTTP and websocket on the same port and domain behind reverse proxy

Question

I wanted to try Node-Red and have installed it on my Ubuntu server. This server runs an apache reverse proxy but I can't get it to work right. If I create a virtualhost for the HTTP connection I can access my Node-Red interface just fine, but it doesn't show me any activity such as online MQTT servers or debug messages. After some googling I found out this is because it also uses websockets and those have to be passed through as well.

And here is the puzzle I didnt manage to solve: I can pass through either HTTP or websockets, but not at the same time. If I pass through HTTP, load the Node-Red webinterface, and then change the reverse proxy settings to WS passthrough, I get full functionality. However I'm not able to reload or reconnect to the Node-Red page because HTTP passthrough was removed.

How do I add both on the same domain and port? or is this not possible at all? Here is some of my apache2 configuration:

<VirtualHost *:80>
ServerName nr.domain.com
Redirect permanent / https://nr.domain.com/
RewriteEngine on
RewriteCond %{SERVER_NAME} =nr.domain.com
RewriteRule ^https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
</VirtualHost>

<VirtualHost *:443>
ServerName nr.domain.com
SSLEngine On
<Location />
ProxyPass http://localhost:1880/
ProxyPassReverse http://localhost:1880/
</Location>

Include /etc/letsencrypt/options-ssl-apache.conf
SSLCertificateFile /etc/letsencrypt/live/nr.domain.com/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/nr.domain.com/privkey.pem
</VirtualHost>

If I add a location with ProxyPass ws:// and so on, the live info and debugger work, but the webinterface is no longer accessible. How do I modify my apache config file in a way that both work?

Answer 1

It looks like you also need to proxy web socket connections as well based on this previous answer.

Try something like this for your configuration.

<VirtualHost *:80>
  ServerName nr.domain.com
  Redirect permanent / https://nr.domain.com/
  RewriteEngine on
  RewriteCond %{SERVER_NAME} =nr.domain.com
  RewriteRule ^https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
</VirtualHost>

<VirtualHost *:443>
  ServerName nr.domain.com
  SSLEngine On
  <Location />
    ProxyPass http://localhost:1880/
    ProxyPassReverse http://localhost:1880/
  </Location>

  # New web socket proxy
  <Location /comms>       
    ProxyPass ws://localhost:1880/comms
    ProxyPassReverse ws://localhost:1880/comms
  </Location>

  Include /etc/letsencrypt/options-ssl-apache.conf
  SSLCertificateFile /etc/letsencrypt/live/nr.domain.com/fullchain.pem
  SSLCertificateKeyFile /etc/letsencrypt/live/nr.domain.com/privkey.pem
</VirtualHost>

Answer 2

To enable both HTTP and WebSocket traffic for Node-Red through your Apache reverse proxy, you need to make some modifications to your Apache configuration. Here's what you can try:

1. Enable WebSocket proxying by adding the following lines to the VirtualHost section for Node-Red:

    <Location /ws>
      ProxyPass ws://localhost:1880/ws
      ProxyPassReverse ws://localhost:1880/ws
    </Location>

This tells Apache to proxy all WebSocket traffic to Node-Red.

2. Modify the existing ProxyPass and ProxyPassReverse directives to exclude the WebSocket endpoint. Add the following line after the tag from the previous step:

    ProxyPassMatch "^/(?!ws)(.*)" "http://localhost:1880/$1"

This tells Apache to proxy all HTTP traffic to Node-Red except for the WebSocket endpoint.

The modified VirtualHost section should look like this:

<VirtualHost *:443>
  ServerName nr.domain.com
  SSLEngine On

  <Location /ws>
    ProxyPass ws://localhost:1880/ws
    ProxyPassReverse ws://localhost:1880/ws
  </Location>

  <Location />
    ProxyPassMatch "^/(?!ws)(.*)" "http://localhost:1880/$1"
    ProxyPassReverse http://localhost:1880/
  </Location>

  Include /etc/letsencrypt/options-ssl-apache.conf
  SSLCertificateFile /etc/letsencrypt/live/nr.domain.com/fullchain.pem
  SSLCertificateKeyFile /etc/letsencrypt/live/nr.domain.com/privkey.pem
</VirtualHost>

Restart Apache for the changes to take effect:

sudo systemctl restart apache2

With these changes, both HTTP and WebSocket traffic should be proxied correctly to Node-Red through your Apache reverse proxy.