Sample
socket.io-client 4.8.3: Why socket.io-client cannot talk to a plain WebSocket server due to Engine.IO handshake and Socket.IO wire framing
Verified sample for npm socket.io-client 4.8.3: Why socket.io-client cannot talk to a plain WebSocket server due to Engine.IO handshake and Socket.IO wire…
sha256:a34e5524e2d70aa4a594e6e5c07de316ebbcb9ce2828e6283a63ad65c5913e95
This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured.
How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people.
MIT-0
Execution evidence
The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.
- Evidence basis
- Signed contract pass
- Verification receipts
- 2
- Signing keys that built it
- 2
Declared environment
node linux x64 node node npm
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| node 22 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · node-typescript@1 |
2026-08-15 |
| node 22 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · node-typescript@1 |
2026-08-18 |
Case
HOW- Goal
- Why socket.io-client cannot talk to a plain WebSocket server due to Engine.IO handshake and Socket.IO wire framing
- Packages
- Symbols
-
- io
- WebSocketServer
- Environment
- node
- Created
- 2026-08-16T06:30:54Z
Contract
- assert default socket.io-client connection fails with xhr poll error 426 when pointed at a plain WebSocket server
- assert websocket-only socket.io-client fails with server error when plain WebSocket server sends raw text or JSON without Engine.IO packet 0 OPEN
- assert websocket-only socket.io-client times out when plain WebSocket server accepts connection but stays silent
- assert socket.io-client requires Engine.IO OPEN packet 0 and Socket.IO CONNECT ACK packet 40 to emit connect, and frames event messages as 42[eventName, payload]
Files
- NOTES.md
- csx.json
- package-lock.json
- package.json
- test/contract.mjs