2 replies

ESP32 Gateway Connection Issue - "invalid-handshake" Error

Problem: ESP32 connects to gateway WebSocket, receives
connect.challenge
connect.challenge
, but when sending
connect
connect
request, gateway closes with
invalid-handshake
invalid-handshake
.

Setup:
- ESP32 (Xteink X4) using arduino-WebSocket-Client
- Gateway v2026.1.23-1 via Tailscale Funnel
- Token auth (
gateway.auth.mode=token
gateway.auth.mode=token
)
- Protocol 3

Connect Request:
{"type":"req","method":"connect","id":1,"params":{"minProtocol":3,"maxProtocol":3,"client":{"id":"gateway-client","displayName":"Grimacegotchi","version":"1.0.0","platform":"esp32","mode":"backend"},"auth":{"token":"ba96d1045b4aa165af99c21d4e5931dab60d1925bf0a792203c5d8f1e2d1bf5e"}}}
{"type":"req","method":"connect","id":1,"params":{"minProtocol":3,"maxProtocol":3,"client":{"id":"gateway-client","displayName":"Grimacegotchi","version":"1.0.0","platform":"esp32","mode":"backend"},"auth":{"token":"ba96d1045b4aa165af99c21d4e5931dab60d1925bf0a792203c5d8f1e2d1bf5e"}}}

What Works:
- WebSocket handshake succeeds
- Gateway sends challenge event
- ESP32 receives challenge and sends connect request
- Gateway receives request (visible in logs)

What Fails:
- Gateway closes connection immediately after receiving connect request
- Error:
cause=invalid-handshake handshake=failed lastFrameType=req lastFrameMethod=connect
cause=invalid-handshake handshake=failed lastFrameType=req lastFrameMethod=connect

- No response sent to ESP32, just closes

Gateway Logs:
[ws] invalid handshake conn=... ua=arduino-WebSocket-Client [ws] → close code=1000 cause=invalid-handshake handshake=failed lastFrameType=req lastFrameMethod=connect
[ws] invalid handshake conn=... ua=arduino-WebSocket-Client [ws] → close code=1000 cause=invalid-handshake handshake=failed lastFrameType=req lastFrameMethod=connect

Tried:
- Changed
id
id
from UUID string to integer
- Verified JSON structure matches schema
- Confirmed
client.id="gateway-client"
client.id="gateway-client"
and
mode="backend"
mode="backend"

- Verified token matches config
- Added delays/loop calls
- Enabled verbose logging

Questions:**
1. Is connect request format correct for token auth?
2. Does token auth require challenge nonce in connect request?
3. Any additional headers/fields needed for ESP32?
4. What does "invalid-handshake" mean here?

Token auth works for web UI. Gateway config shows tokens match. Any insights appreciated!