Terminal WebSocket fails with HTTP 400 — evo-nexus-dashboard image is missing websocket-client

[arksigma]

Summary

The published evoapicloud/evo-nexus-dashboard:latest image ships its Python venv (/workspace/.venv) without the websocket-client package. This silently disables the /terminal/ws proxy, so the in-browser terminal WebSocket never connects — the upgrade request returns HTTP 400 from Werkzeug.

Environment

• Image: evoapicloud/evo-nexus-dashboard:latest
• Deployment: docker-compose.hub.yml (unmodified), ports 8080 + 32352 mapped
• Host: Linux, Docker Compose

Symptoms

The dashboard loads fine, but the terminal never connects. Access log shows the WS upgrade repeatedly rejected:

"GET /terminal/api/health HTTP/1.1" 200 -
"GET /terminal/ws HTTP/1.1" 400 -

Diagnosis

The frontend connects same-origin: ws://<host>:8080/terminal/ws, which the Flask dashboard is meant to proxy to the Node terminal-server on :32352.

• Direct handshake to the terminal-server → 101 Switching Protocols (server itself is healthy):

  curl -i -N -H 'Connection: Upgrade' -H 'Upgrade: websocket' \
       -H 'Sec-WebSocket-Version: 13' -H 'Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==' \
       http://localhost:32352/terminal/ws
  # HTTP/1.1 101 Switching Protocols
  

• Same handshake through the dashboard proxy → 400 from Werkzeug:

  curl ... http://localhost:8080/terminal/ws
  # HTTP/1.1 400 BAD REQUEST
  # Server: Werkzeug/3.1.8 Python/3.12.13
  

Container logs reveal the cause — register_websocket_proxy disables itself because websocket-client is absent:

terminal_proxy.register_websocket_proxy: websocket-client not installed;
WebSocket proxy disabled. Add `websocket-client` to dependencies.

Confirmed missing from the venv the app actually runs under (start-dashboard.sh → uv run python .../app.py):

$ docker exec evonexus-dashboard /workspace/.venv/bin/python3 -c "import websocket"
ModuleNotFoundError: No module named 'websocket'

With websocket-client disabled, the WS upgrade falls through to the plain-HTTP proxy route, and Werkzeug rejects the Upgrade request with 400.

Fix

Add websocket-client to the dashboard's dependencies so it's installed into /workspace/.venv at image build time. (flask-sock is already present; only websocket-client is missing.) The code's own warning message already points to this.

Verification

Reinstalling the package into the running venv and restarting resolves it completely — /terminal/ws then returns 101 Switching Protocols and the browser terminal connects:

docker exec evonexus-dashboard sh -c 'cd /workspace && uv pip install websocket-client'
docker restart evonexus-dashboard