I have attempted several configs to get websockets to properly proxy with apache, however I am still running into this error.
failed: Error during WebSocket handshake: Unexpected response code: 400
Below is the current applicable part of the apache config.
RewriteRule ^/jupyter$ /jupyter/ [R]
RewriteCond %{HTTP:Upgrade} =websocket [NC]
RewriteRule ^/jupyter/(services/[^/]*)|(user/[^/]*)/(api/kernels/[^/]+/channels|terminals/websocket)/? wss://localhost:8000/$1 [P,L]