[robobun]

Problem

• After its response finished, a request whose body still arrives gets no socket 'timeout'. The server destroys the socket. Node v26.3.0 runs the req.setTimeout() callback.
• onNodeHTTPServerSocketTimeout (src/js/node/_http_server.ts:252) reads socket[kRequest]. detachSocket (:3904) clears it when the response finishes.
• A socket that a 'timeout' listener kept never times out again (:1628).

Fix

• The handler reads socket.parser.incoming, as Node's socketOnTimeout does. That slot lives until the request ends. kRequest is removed.
• Bun's own clause: a stream-destroyed request never turns complete. It is told only while a response is on the socket.
• A stand-in takes the slot of a socket timer that fired. Socket activity arms a new timer through it, as refresh() does in Node.
• Verified: test/js/node/http/node-http-server-timeouts.test.ts, 11 of 16 new tests fail on main. Self-reviewed: 11 concerns raised, 10 addressed. Not taken: Node's Expect close rule (node:http: close the connection after a final response to an unanswered Expect: 100-continue #45189).

Background

• socket.parser stands in for Node's HTTP parser. Its incoming is the request that the connection receives.
• One timer per socket serves server.timeout, req.setTimeout() and the keep-alive timeout. With no 'timeout' listener the server destroys the socket.
• Considered kRequest kept past the detach: two slots for one fact. A native callback that completes a stream-destroyed request held an unref'd server's event loop.

Downsides

• A req.setTimeout() callback runs again at the keep-alive timeout while the upload stalls, as in Node. A second answer throws ERR_HTTP_HEADERS_SENT. Main closed the socket.
• A stream-destroyed request still hears no 'timeout' after its response finished (8 of 75 probe cells).
• Each socket timer that fires allocates one 3-field object.

Notes

Repro. It runs under Node and Bun.

const http = require("node:http"), net = require("node:net");
const events = [];
const server = http.createServer({ keepAliveTimeout: 200, keepAliveTimeoutBuffer: 0 }, (req, res) => {
  req.on("timeout", () => events.push("req"));
  server.on("timeout", () => events.push("server"));
  req.on("error", () => {});
  req.resume();
  res.end("early"); // the response ends before the request body does
});
server.listen(0, "127.0.0.1", () => {
  const s = net.connect(server.address().port, "127.0.0.1", () =>
    s.write("POST / HTTP/1.1\r\nHost: x\r\nContent-Length: 10\r\n\r\nabc")); // 3 of 10 body bytes
  s.on("data", () => {});
  s.on("error", () => {});
  setTimeout(() => {
    console.log(JSON.stringify(events));
    process.exit(0);
  }, 1200);
});

Runtime	Output
Node v26.3.0	["req","server"]
Bun 1.4.3-canary.1, main a950fc5	["server"]
this PR	["req","server"]

With req.setTimeout(30000, cb) and no server listener, Node runs cb and keeps the socket. Main never runs cb and destroys the socket.

No user reported this. Probes against Node v26.3.0 found it, and #43561 listed this row as a difference that remained.

What Node does. socketOnTimeout reads this.parser?.incoming and tells it when !req.complete. clearIncoming keeps that slot until the request has ended. Bun maintains the same slot on a connection that the server accepts. The dispatcher sets it. The request's EOF clears it one tick later. A response that finishes clears it only for a request that has ended.

Probes against Node v26.3.0 (debug builds, main a950fc5, Linux x64). A cell is one scenario with one set of 'timeout' listeners (request, response and server, request only, or none). It is equal when the events and the side that closed the connection are equal.

Probe	main	this PR
25 scenarios, 75 cells	50	67, 0 worse than main
the same with two-read rows for stream-destroyed requests, 99 cells	66	83, 0 worse than main
11 call orders (listener added after 'finish', req.setTimeout() after 'finish', res.setTimeout(), socket.setTimeout(0), a second request, and so on)	3	11
a timeout that a listener kept, then more body bytes, 3 rows	1	3

The 17 cells that this PR fixes: a response that ends before the body (body read, unread, read with a 'data' listener, chunked, keepAliveTimeout: 0 with server.timeout, res.end() from setImmediate, req.setTimeout(ms, cb)), and a stalled POST that is answered early behind a pipelined GET.

What stays different from Node.

• A request that the stream destroyer destroyed (a failed stream.pipeline(), a for await break, Readable.toWeb(req).cancel()): 8 of the 75 cells, the same as on main. Node's parser sets complete on such a request when its body has arrived. In Bun IncomingMessage#_destroy lets go of the native body, so complete stays false and the server cannot tell a body that stalls from one that arrived. The clause req.destroyed && !this._httpMessage keeps main's rule for it. Without the clause such a request kept an idle keep-alive socket open after its whole body had arrived. That is why the first version of node:http: emit 'timeout' on the pipelined request that is still being received #43561 (cfc4149), which read parser.incoming, went back to kRequest. The existing test "a pipelined request that stream.pipeline() destroyed does not keep the idle keep-alive socket open" guards it. Three test.todo rows hold Node's result for the day complete is right. node:http: closeIdleConnections() reads req.complete, and a destroyed request sets it #44310 works on that.
• A final response to an unanswered Expect: 100-continue: Node sends Connection: close and closes. Bun keeps the connection (node:http: close the connection after a final response to an unanswered Expect: 100-continue #45189), so a request listener is now told at the keep-alive timeout, where main closed the socket.
• A connection that node:http parses in JS (server.emit('connection', socket), allowHTTP1) has no socket timer on main. node:http, node:http2: give emit('connection') and allowHTTP1 connections the server's timers and error path #46185 adds one and feeds this handler through socket[kRequest]. After this PR it has to set parser.incoming.

The timer. On main onSocketTimeoutTimerExpired treats a timer that fired in two ways, and both leave a socket that a listener kept without a timeout.

• A keep-alive timer leaves its slot, because the response-finish fast path trusts a timer that is in the slot. _unrefTimer() then finds nothing to refresh.
• A server.timeout or req.setTimeout() timer stays in the slot. If keepAliveTimeout + keepAliveTimeoutBuffer has the same duration, the fast path takes that dead timer for the keep-alive timer, and the idle connection never times out.

Node's refresh() arms a fired timer again. Now a stand-in with only refresh() takes the slot in both cases. Its refresh() arms a new timer with the socket's timeout, unless a request that came since changed that timeout. The fast path finds no _idleTimeout on the stand-in and arms a real timer. _unrefTimer() and socket.setTimeout() are the same code blocks as on main.

A callback that answers twice. req.setTimeout(300, cb), cb answers 408 with no check of res.headersSent, the upload stalls, and the keep-alive timeout is 500 ms.

Runtime	Result
Node v26.3.0	cb runs at 300 ms and at 800 ms. The second res.writeHead() throws ERR_HTTP_HEADERS_SENT. With no 'uncaughtException' listener the process exits with code 1.
main a950fc5	cb runs once. The server closes the socket at the keep-alive timeout.
this PR	as Node

A peer chooses when this runs: it stalls an upload behind a response. A callback that checks res.headersSent is not affected. Node has no guard here, and this PR adds none: a guard would hide the 'timeout' that the request listens for. With a keep-alive timeout of 300 ms too, Node and this PR give the same result. Main runs cb once and never closes the socket.

Measurements (Linux x64).

What	main	this PR	How
kRequest writes per 1,000 keep-alive requests	1,999	0	a setter on the slot, GET and POST
parser.incoming writes per 1,000 requests	2,000	2,000	the same
bytecode instructions, dispatcher onNodeHTTPRequest	759	755	BUN_JSC_dumpGeneratedBytecodes=1
bytecode instructions, detachSocket	31	22	the same
_unrefTimer, socket setTimeout, emitResponseFinish, onResponseFinishHandleSocket		same code blocks	the same
bytecode instructions, onSocketTimeoutTimerExpired (runs when a socket timer fires)	74	77	the same
bytecode instructions, rearmFiredSocketTimer (new, runs on the first activity after a timer fired)		25	the same
bytecode instructions, onNodeHTTPServerSocketTimeout (runs on a socket 'timeout')	42	50	the same
allocations		0 per request, 1 object with 3 fields per socket timer that fires	the diff
host functions, native code		0 added	the diff has no native file
builtin JS in the release binary (.bun_builtins)	2,712,077 bytes	2,711,747 bytes	bundle-modules.ts --debug=OFF on both trees

valgrind, perf, bloaty and strace are not on this machine and cannot be installed, so there is no instruction count.

Side effect. On main an open upgraded socket keeps its Upgrade request alive through socket[kRequest], because no response detaches there. A probe (upgrade, keep the socket, ten forced collections) finds the request alive on main and collected with this PR.

Self-review. The first cut of this branch also had a native handle.discardBody(cb). With it a stream-destroyed request completed at its last chunk, with no work per read. All 75 cells were equal to Node. The review found that it held the event loop. The case: an unref'd server, an upload that backpressure paused and the stream destroyer destroyed, and a client that closes. The server stayed up for the whole keep-alive timeout and used 2.8 CPU-seconds in 3 s. Main exits in 50 ms. It also completed a body that arrives in two reads, where Node stops reading. That half is not in this PR. Of the 11 concerns:

• 5 were about the native half and went away with it.
• 4 are addressed here. Tests for a callback that answers again and for a listener that throws. Tests for the conditions of the stand-in. The test for a server listener that keeps the socket. This description (repro, Node's source, no user report, node:http: emit 'timeout' on the pipelined request that is still being received #43561, node:http: close the connection after a final response to an unanswered Expect: 100-continue #45189).
• 1 is on main now: the test for a stream destroy plus res.end() in one tick came with Hardening follow-up: fix regressions from #46021 and more crashes #46270.
• 1 is not taken: Node's rule that closes the connection behind a final response to an unanswered Expect: 100-continue. node:http: close the connection after a final response to an unanswered Expect: 100-continue #45189 implements it.

Tests. 16 new tests and 3 todo rows in node-http-server-timeouts.test.ts. On main's src/ 11 fail. The other 5 guard rules that main already has. A complete request gets no 'timeout'. A new request ends the idle period. A stream-destroyed request is told while its response is pending (3 rows). One of the 11 is the case of two equal durations. Every expectation, the todo rows too, passes under Node v26.3.0 with a bun:test shim. The 16 tests and the existing pipeline() test passed 40 of 40 runs under load (8 at once on 4 cores).

Suites run with the debug build: test/js/node/http/ (39 files) and the 512 vendored test-http-* and test-https-* files. What fails here also fails, or times out at the same rate, with main's JS: tests that start several subprocesses and run into the 5 s limit, test-http-agent-keepalive.js (a 1 ms wait), test-http-client-timeout-option.js, test-https-timeout.js.

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Walkthrough

Changes

HTTP server timeout handling now reads the active request from the parser. Fired socket timers use a refreshable stand-in, with rearming conditional on the unchanged timeout value. Tests cover timeout events, timer ordering, listener errors, and destroyed streams.

HTTP server timeout handling

Layer / File(s)	Summary
Request timeout eligibility and events src/js/internal/http.ts, src/js/node/_http_server.ts, test/js/node/http/node-http-server-timeouts.test.ts	Removed the obsolete kRequest symbol and socket tracking. Socket timeout handling reads parser.incoming and excludes destroyed requests without attached responses. Tests cover stalled bodies, timeout events, listener errors, and destroyed streams.
Fired socket timer rearming src/js/node/_http_server.ts, test/js/node/http/node-http-server-timeouts.test.ts	A fired socket timer uses a refreshable stand-in. The socket timeout is reapplied only when its value is unchanged. Tests cover rearming and keep-alive timeout ordering.

Possibly related issues

• oven-sh/bun#43381: The change covers timeout-driven request-socket handling and close timing, but not the issue’s transport-error or write-cancellation cases.

Suggested reviewers: jarred-sumner

Priority: ➖ Normal

Merge Risk: 🔵 Low · up to 3bee7

A specific destroyed partial-body request lifecycle may miss its expected timeout notification; this is bounded follow-up risk rather than a merge blocker.

Pre-merge checks: 4

Check name	Status	Explanation
Title check		The title clearly identifies the primary change: reading parser.incoming in the socket timeout handler to match Node behavior.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.
Description check		The description provides detailed coverage of the change, motivation, limitations, and verification results. It does not use the template headings exactly, but it includes the required information und…

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[robobun]

^{Updated 10:05 PM PT - Oct 21st, 2026}

❌ @robobun, your commit 3bee773 has 2 failures in Build #130500 (All Failures):

• test/js/bun/http/serve-body-leak.test.ts - code 1: error: body-leak fixture exited (1) before sending its URL on 🍎 any aarch64
• test/js/node/test/parallel/test-tls-socket-default-options.js - crash reported on 🍎 27 aarch64

---

🧪   To try this PR locally:

bunx bun-pr 46403

That installs a local version of the PR into your bun-46403 executable, so you can run:

bun-46403 --bun

[claude]

Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.

Beyond the inline findings, I also checked the stand-in object the keep-alive path now leaves in socket[kSocketTimeoutTimer] against every consumer of that slot: clearTimeout(standIn) in _destroy/close/setTimeout(0) is a no-op (Timer.rs clear_timer returns early for a non-Timeout object), and socket.setTimeout(ms) / onResponseFinishHandleSocket read _idleTimeout, which is undefined on the stand-in, so they allocate a fresh Timeout rather than refreshing it. No kRequest references remain in the http1 server path (remaining hits are http2's and ws's own symbols).

Extended reasoning...

The change swaps the socket 'timeout' handler's request lookup from a private slot to parser.incoming, removes kRequest, and adds a refresh-only stand-in so a keep-alive timer that a listener survived can be re-armed by later socket activity; no security-sensitive surface. Two findings were posted inline, so this note only records the slot-consumer and stale-reference checks that were ruled out.

[robobun]

Status: ready for review.

How to reproduce the bug:

1. Save the script from the Notes of this PR as early-end.js. Its listener ends the response when the client has sent 3 of 10 body bytes. The body then stalls.
2. Run it with Node v26.3.0. It prints ["req","server"].
3. Run it with Bun 1.4.3-canary.1, or with main a950fc5. It prints ["server"].
4. Run it with this branch. It prints ["req","server"].

Test: bun bd test test/js/node/http/node-http-server-timeouts.test.ts. With main's src/, 11 of the 16 new tests fail. With this branch all of them pass.

PR: #46403

[coderabbitai]

Actionable comments posted: 1

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Inline comments:
Review comments at @src/js/node/_http_server.ts:
- Line 1632: Update rearmFiredSocketTimer to destructure or otherwise cache
msecs once before the conditional, then use that local value for both the
comparison and socket.setTimeout call while preserving the existing socket
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[claude]

I re-reviewed the PR after the second commit (4db1b02) and found no new bugs; since this reworks the per-socket timer lifecycle in the node:http server hot path, a human look at the timer state machine would still be worthwhile.

What was reviewed:

• The stand-in now installed unconditionally in onSocketTimeoutTimerExpired (src/js/node/_http_server.ts:1624), traced through every kSocketTimeoutTimer consumer: the setTimeout() refresh fast path and the response-finish fast path both miss it (no _idleTimeout), _unrefTimer() re-arms through rearmFiredSocketTimer only while socket.timeout is unchanged, and clearTimeout() on the plain object is a no-op in src/runtime/timer/Timer.rs (clear_timer falls through for non-Timeout objects).
• The parser.incoming lifecycle the new 'timeout' handler relies on is unchanged by this PR (set at dispatch :804, cleared at request EOF a tick after 'end' and at response finish only when readableEnded), so the handler sees the same slot Node's socketOnTimeout reads; no remaining kRequest references in the server path.
• The _onTimeout() write-in-progress branch (:1966) that re-arms via _unrefTimer() now works in keep-alive mode too, where main left the slot empty.
• The new test for a server.timeout equal to the keep-alive total covers the non-keep-alive fire path; the .todo.each rows carry the observed-failure comment.

Extended reasoning...

The diff touches src/js/node/_http_server.ts (socket 'timeout' handler now reads parser.incoming; a fired socket timer is replaced in its slot by a refresh-only stand-in in both timer modes), removes the kRequest symbol from src/js/internal/http.ts, and adds 16 tests to test/js/node/http/node-http-server-timeouts.test.ts. No security-sensitive surface is involved; the risk is lifecycle correctness of a shared per-connection timer slot that four code paths read with different assumptions. The second commit addresses the pre-existing non-keep-alive gap flagged in the prior run and ships a test for it. I traced each slot consumer and the parser.incoming set/clear sites and found them consistent, but the interaction of keep-alive budget granting, stand-in re-arming and listener-driven setTimeout(0) is intricate enough that it should not merge on an automated approval alone; no CODEOWNERS entry covers these files and no third-party objections are outstanding.

Still open from earlier reviews (1):

• Unresolved: 1 minor or pre-existing.

[claude]

I re-reviewed the latest push and found no bugs; the stand-in now covers both the keep-alive and server.timeout branches, which closes the earlier gap in the server.timeout path. Because this reworks the per-socket timer state machine and the request-side 'timeout' rule in node:http, a human look at the timing semantics is still worthwhile.

What was reviewed:

• The stand-in in socket[kSocketTimeoutTimer]: it has no _idleTimeout, so onResponseFinishHandleSocket and setTimeout() always arm a real timer instead of refreshing it; clearTimeout(standIn) in #onClose, _destroy and setTimeout(0) is a no-op in clear_timer (src/runtime/timer/Timer.rs) for non-Timeout objects.
• _unrefTimer() and _onTimeout()'s pending-write re-arm now reach rearmFiredSocketTimer, which only re-arms when socket.timeout still equals the fired interval, so a request that replaced the timeout (server.timeout 0 or a new value) is not overridden.
• kRequest removal: no remaining readers in src/js (ws.ts and http2.ts define their own symbols); parser.incoming clearing at EOF, response finish (readableEnded) and socket close is unchanged, so retention of a destroyed request on an idle socket is the same as on main.
• Tests: new cases await observable events, release server/client in finally, and the subprocess case drains stdout/stderr/exited together; the test.todo rows carry the observed divergence.

Extended reasoning...

The change touches src/js/node/_http_server.ts (socket 'timeout' handler now reads parser.incoming, a refresh-only stand-in replaces a fired socket timer in both timer modes), removes the kRequest symbol from src/js/internal/http.ts, and adds about 490 lines of tests to test/js/node/http/node-http-server-timeouts.test.ts. No auth, crypto or injection surface; the only security-relevant aspect is the documented Node-parity behavior where a stalled upload can re-run a req.setTimeout callback after headers were sent, which was raised in a prior run and is now covered by a test. The latest commits addressed the prior inline finding about the server.timeout branch leaving a dead timer in the slot. Deferring rather than approving because the per-socket timer state machine has several interacting fast paths (keep-alive refresh, idle-start budget, request arrival) and the subtle divergence clause for stream-destroyed requests merits a maintainer's judgment; no CODEOWNERS entry covers these files and no CHANGES_REQUESTED review is outstanding.