proposal: add req.signal (AbortSignal) for automatic client disconnect detection #62481
Description
What is the problem this feature will solve?
Currently, when we handle HTTP requests with async operations (such as DB queries or fetch calls), there isn't a straightforward way to cancel pending work if a client disconnects. The common workaround is to manually wire up req.on('close') or check req.destroyed:
server.on('request', async (req, res) => {
const ac = new AbortController();
req.on('close', () => ac.abort());
const data = await fetch('https://slow-api.com', { signal: ac.signal });
res.end(JSON.stringify(data));
});This is boilerplate that every server framework ends up reimplementing.
Design considerations
Lazy initialization AbortController only created when req.signal is accessed (zero overhead for code that doesn't use it)
Socket close = abort no conditional logic, signal aborts whenever the socket closes
_destroy integration req.destroy() also triggers abort
configurable: true allows framework override
HTTP/2 parity Http2ServerRequest should eventually get the same property (follow-up)
Prior art
Web Fetch API: Request.signal
Deno: request.signal on Deno.serve() handler
@nodejs/http @nodejs/http2
What is the feature you are proposing to solve the problem?
add a lazy signal getter to IncomingMessage that returns an AbortSignal which aborts when the underlying socket closes:
server.on('request', async (req, res) => {
const data = await fetch('https://slow-api.com', { signal: req.signal });
res.end(JSON.stringify(data));
});What alternatives have you considered?
No response
Activity
mcollina commentedon Mar 28, 2026
Go for it and open a PR.
Renegade334 commentedon Mar 29, 2026
Does this reduce to the general case of "we should have a
node:eventsutility to make an AbortSignal from an EventEmitter"? Sounds pretty similar to the notion of creating a Promise from an EE (ie.events.once()).mertcanaltin commentedon Mar 29, 2026
I think
req.signalshould still be a dedicated property though,it needs to align with the web platform (
Request.signalin Fetch API, Deno),and it has to handle both socket
closeandreq.destroy()together, which a generic utility wouldn't cover on its own.that said, a general
events.signalFrom()could be a great companion in a separate proposal, they're not mutually exclusive.damianremington274-blip commentedon Mar 29, 2026
http: add req.signal to IncomingMessage
http: add req.signal to IncomingMessage
http: add req.signal to IncomingMessage