Apache WebSocket only works on Reverse Proxy if included port number

Question

I have an AngularJS with Spring REST MVC backend application. I'm trying to set up reverse proxy for the application, with the help of the proxy server admin. He got almost everything to work except for the websocket. The weird thing is if I added the port number to the reverse proxy URL, then websocket works too. For example:

https://proxy.example.com/myApp doesn't work with websocket. However, https://proxy.example.com:8443/myApp works with websocket.

I'm at a lost here. We've try many different things. Could you see what is missing in the configuration?

<VirtualHost *:443>
    ServerName proxy.example.com
    ServerAlias testServer
 
    SSLEngine on
    SSLProxyEngine on
    SSLCertificateFile /etc/ssl/certs/example.com_07012022.cer
    SSLCertificateKeyFile /etc/ssl/certs/example.com_07012022.pem
 
    ProxyPass / https://proxy.example.com:8443/
    ProxyPassReverse / https://proxy.example.com:8443/
 
    RewriteEngine on
    RewriteCond %{HTTP:Upgrade} websocket [NC]
    RewriteCond %{HTTP:Connection} upgrade [NC]
    RewriteRule .* "wss://proxy.example.com:8443/$1" [P,L]
</VirtualHost>

The ProxyPass and ProxyPassReverse doesn't look right, but I couldn't even hit the homepage with the following config:

ProxyPass / https://localhost:8443/
ProxyPassReverse / https://localhost:8443/

Thanks. Appreciate the help.

question from:https://stackoverflow.com/questions/65852939/apache-websocket-only-works-on-reverse-proxy-if-included-port-number

Answer 1

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