WebSocket: "close" is not emitted on error

[kettanaito]

Bug Description

When a WebSocket connection is closed due to an error, the close event doesn't get emitted.

Reproducible By

Run this in Node.js REPL (assumes undici is installed):

const { WebSocket } = require('undici')

let ws = new WebSocket('wss://example.com/non-existing-url')
ws.onerror = () => console.log('ERROR!')
ws.onclose = () => console.log('CLOSE!')

Expected Behavior

The WebSocket instance must dispatch two events in the following order:

ERROR!
CLOSE!

Actual behavior

It doesn't. Only the error event gets dispatched. The close event never gets dispatched, which I believe to be incorrect.

ERROR!

Logs & Screenshots

I can also verify that the browser implementation of WebSocket behaves correctly:

Environment

I believe the environment is irrelevant here.

• undici 6.6.2

Additional context

• WHATWG WebSocket standard: Closing connections
• WebSocket error event on MDN:

The error event is fired when a connection with a WebSocket has been closed due to an error (some data couldn't be sent for example).

[Uzlopak]

@KhafraDev

[kettanaito]

I'm also open to contributing a fix to this if we conclude that it's indeed an issue! Would appreciate guidance with tests during the code review.

[Uzlopak]

@kettanaito

Imho it was already fixed by @KhafraDev via #3628 and #3651 .

Just not backported?!

[kettanaito]

Oh, that sounds nice! I'm trying that on Node.js v18, I believe. I'd love to have a backport to that version.

[KhafraDev]

backporting to v6 will be difficult because websocket has had significant rewrites

[kettanaito]

@KhafraDev, understandable. Is v22 the minimal to use to get this fix then? (Undici v7)

[fawazahmed0]

@KhafraDev There is also issue with readyState in undici@main package

let ws = new WebSocket('wss://example.com/non-existing-url')
ws.onerror = () => console.log('ERROR!')
ws.onclose = () => console.log('CLOSE!')
setTimeout(()=>console.log(ws.readyState),7000)

Undici@main Output:

ERROR!
CLOSE!
0

Firefox Output:

ERROR!
CLOSE!
3

Safari Output:

ERROR!
CLOSE!
3

chrome Output:

ERROR!
3

[KhafraDev]

@fawazahmed0 I have opened a PR with a fix, thanks.