/websockify endpoint fails when web server is served with a path prefix

[Nedved-liao]

Describe the bug
This problem can be solved by modifying app/ui.js in novnc, but the modification does not take effect in kasmVNC

more detail:
novnc/noVNC#1737

How to solve this problem

[mmcclaskey]

No code needs to be modified, use a reverse proxy. KasmVNC is used with Kasm Workspaces and in that configuration the KasmVNC session is has a long prefix, for example,

wss://192.168.25.2/desktop/6603159b-49b2-45e1-8c3f-f080c19081db/vnc/websockify

The GUID in the path a session ID that corresponds to a container. NGINX proxies the session to the correct container and alters the location when proxied to KasmVNC. When the request gets to KasmVNC it is at the correct URI.

You should be able to do something similar.