node:http2: emit 'aborted' only while the writable side is open by robobun · Pull Request #45056 · oven-sh/bun

robobun · 2026-10-12T08:54:49Z

Problem

node:http2 emits 'aborted' on a stream whose writable side ended. Node emits it only "if the Http2Stream writable side has not been ended".
A 204 after a consumed POST body always fires it, as does end(body) before a peer reset. bun 1.3.13 does neither. No user reported it.
The aborted handlers (src/js/node/http2.ts:4072, :5078) tested old_state != 5 && old_state != 7: the state of the wire.

Fix

abortIfWritableOpen() holds node's closeStream() rule for both handlers, close() and _destroy(). It also covers what only node has ended: closed, pending trailers, pushed, HEAD.
Native runs the callbacks of dropped writes after it calls the aborted handler. A callback that calls end() then cannot hide the abort.
Verified: test/js/node/http2/node-http2-aborted.test.ts, 52 cases. Node v26.3.0 and v26.11.1 pass 52, main fails 32. Self-reviewed: 34 concerns raised, 30 addressed.

Background

H2FrameParser is the native session. It calls the aborted handler for a peer RST_STREAM(CANCEL), a closed server socket and an aborted request({signal}).
With only the handlers changed, 13 cases fail. node:http2: destroy streams before the native sweep in session teardown #42717, node:http2: free a request's slot when its stream closes on the wire, abort request({ signal }) from JS only #42763 and node:http2: fail a dropped write with ECANCELED, keep no write callback in native #44881 later remove the native part.

Downsides

write(body, () => end()) with the body in the socket buffer, then signal.abort() or a peer reset: no 'aborted'. Main and node v26.11.1 emit it.
Compat: a disconnect that cuts res.end(body) no longer sets req.aborted, as in node. res.writableFinished stays true (node: false). Only stream.rstCode shows the cut.
One helper call per stream close (5 bytecode instructions). Size: +1,224 bytes.

Notes

The clean exchange. A server reads a POST body to its end, then calls stream.respond({ ":status": 204 }). The events of the server stream:

node v26.3.0, v26.11.1   finish close            aborted === false   finished(stream): ok
main                     aborted finish close    aborted === true    finished(stream): ERR_STREAM_PREMATURE_CLOSE
this PR                  finish close            aborted === false   finished(stream): ok

respond(200, { endStream: true }) and a compat res.end() after writeHead(204) do the same. On main, 200 such exchanges emit 200 'aborted' events. Fastify 5.2.2 runs its onRequestAbort hook when req.aborted is true at 'close': 50 of 50 requests on main, 0 of 50 on node, on bun 1.3.13 and with this PR.

Node. closeStream() decides 'aborted' for every close path (core.js#L2019-L2031). It runs one time for a stream: onStreamClose (L602-L603), close() (L2424-L2425) and _destroy() (L2468-L2470) call it only for a stream that is not closed. _destroy() calls it before push(null). Node ends the writable side of a HEAD request's stream (L401-L405) and of a pushed stream on the client (L425) when it creates them. request() ends a request without a body before it submits the request (L1888-L1890). socketOnClose closes every stream before it destroys one (L3578-L3581).

What changes in src/js/node/http2.ts.

abortIfWritableOpen(stream) is the rule and the emit. The caller keeps end(), the closed flag and rstCode.
The two aborted handlers call it in place of the old_state test. close() and _destroy() call it in place of their own copies, and now before push(null), as node does. push(null) can run a 'data' or 'readable' listener that calls end().
request() calls req.end() for a request without a body in the three branches that reject it before a stream id exists: a :path with a space, content-length, no stream id left. The branch for an aborted signal already did.
close() on a pushed client stream destroys the stream, and _destroy() sends its one reset. The writable side of that stream cannot finish, so close() waited for a 'finish' that does not come. See the table below.

The checks of the helper.

Check	Reason	Removed by
`_writableState.ending`	Node's rule.
`Closed`	Node calls `closeStream()` one time. Bun closes a stream inside `respond()` when END_STREAM leaves on the HEADERS frame and the request is complete. `respond()` calls `end()` after that.
`WantTrailer`	Bun emits `'wantTrailers'` inside `end(chunk)`, before the writable side is marked as ending. Node emits it later.
pushed stream on the client	Node ends it at creation.	#43534
server stream of a HEAD request	Node ends it at creation.	no PR

After a Closed, WantTrailer or HEAD decision the caller still calls end(), so 'finish' and 'close' come as before. A pushed stream is not ended, as on main. No user reported the last three cases. They follow from node's source.

One test for each check. Each mutation of the built module fails these cases of the new file:

Mutation	Failing cases
`ending` check removed	18
`Closed` check removed	3
`WantTrailer` check removed	2
pushed-stream check removed	2
HEAD check removed	2
HEAD check without the server test	1
repeat guard removed	10
caller does not call `end()` after a `Closed`, `WantTrailer` or HEAD decision	3
`_destroy()` decides after `push(null)`	1
`close()` decides after `push(null)`	2
`close()` does not destroy a pushed stream	1
`close()` sends its own reset for a pushed stream (two RST_STREAM frames)	1
`request()` without `end()`, one branch at a time	1, 1, 1

Only the two handlers. With the ending and pushed-stream checks in the two handlers only, and the rest of the JS as on main, 13 of the 52 cases fail.

The native part. Stream::free_resources drops the queued DATA frames of a stream and calls the callback of each dropped write. On main, abort_stream and emit_abort_to_all_streams did that before they called the JS aborted handler. A callback that calls end() then ran first, and the handler saw an ended stream. write(body, () => end()) followed by a socket close reached the 'aborted' listener with ending === true. The old rule emitted anyway, because it did not read ending.

Now the two producers take the callbacks out of the queue, free the stream as before, call the handler, and run the callbacks last. emit_abort_to_all_streams runs them after the last stream, because a callback can end another stream. This is the order of node v26.3.0 and v26.11.1 for a socket close.
The stream's queued bytes, its slot and its JS context are released before the handler runs, as on main. A request() from an 'aborted' listener is accepted with 12 MiB queued on the aborted request (a test).
gdb on debug builds, for each aborted stream: the number of free_resources calls and of onAborted dispatches is equal to main in the three producers. The callback of a dropped write comes after the dispatch in 3 of 3 producers (main: 1 of 3).
With the JS change and main's native order, 4 cases fail: write(body, () => end()) on socket close and on signal abort, the two-stream case, and write(body, () => session.destroy()). In the last case main never closes the stream.
The guard is temporary. node:http2: destroy streams before the native sweep in session teardown #42717 removes emit_abort_to_all_streams and node:http2: free a request's slot when its stream closes on the wire, abort request({ signal }) from JS only #42763 removes abort_stream. node:http2: fail a dropped write with ECANCELED, keep no write callback in native #44881 keeps no write callback in native.
The server socket-close route stays native in this PR. With a sweep from JS (forEachStream(streamCancel), as the client has), rstCode reads 0 inside an 'aborted' listener (main and node: 8). node:http2: destroy streams before the native sweep in session teardown #42717 makes that change, and node:http2: store the code of close(code) before its listeners run #44848 stores the code first.

Rows. Release builds of main (6c1eb06) and of this PR on that commit. Node v26.3.0 and v26.11.1 agree on every 'aborted' row.

Probe	Rows where node emits no `'aborted'`	Wrong on main
Server and client matrix	16	14
The four reported rows	4	4
13 transports, core and compat API	36	36

The control rows (writable side open) still emit one time. bun 1.3.13 does not emit on RST_STREAM(CANCEL) or after a 204. It does on socket close and on signal abort.

Example, server stream.end(Buffer.alloc(1 << 20)), the raw client takes 65535 bytes and sends RST_STREAM(CANCEL):

node v26.3.0   close
main           aborted(ending=true) close
this PR        close

Not changed (same on main).

The error sweep. session.destroy() on a client, and a GOAWAY with an error code, drop the queued writes and decide 'aborted' one tick later. write(body, () => end()) then emits no 'aborted' (node emits). One todo test. The callback order of this PR does not help there (checked with a scratch build): the streamError handler decides in _destroy(), on the next tick, and the callbacks run before that tick. A callback that calls session.destroy() during a GOAWAY with an error code leaves the stream without 'close'. node:http2: destroy streams before the native sweep in session teardown #42717 destroys the streams before the sweep.
A write completes when the socket buffers it. See the first Downsides bullet. One todo test (the signal route. Node v26.3.0 does not read a peer reset while its write is pending, so the reset route has no test that both node versions run).
The compat res.writableFinished is true after a response that was cut. See the table below.
rstCode is 0 and not 8 for a server pushed stream when the socket closes (node:http2: destroy streams before the native sweep in session teardown #42717).
closed is false and rstCode is not set inside 'aborted' listeners of close() and _destroy() (node:http2: store the code of close(code) before its listeners run #44848).
A stream is destroyed inside respond() when END_STREAM leaves on the HEADERS frame of a complete request. Node destroys it later.
request() on a destroyed session returns a GET stream that is not ended, so it emits 'aborted'. Node ends it first. node:http2: validate request() headers and options before the session state #43536 moves that check below the endStream handling.
A signal abort on a stream that has not ended: finished() rejects with ERR_STREAM_PREMATURE_CLOSE, node with ABORT_ERR (node:http2: free a request's slot when its stream closes on the wire, abort request({ signal }) from JS only #42763).
A pushed stream on the client (node:http2: let a client close a pushed stream #43534) and the server stream of a HEAD request have writableEnded === false. Node: true.
node:http2: never send or accept DATA before the response HEADERS #43558, node:http2: keep the data that arrived before a peer's RST_STREAM(NO_ERROR) #43754 and node:http2: store the code of close(code) before its listeners run #44848 add or change a copy of the rule. They can call abortIfWritableOpen() after this PR. node:http2: let the server judge content-length on a bodiless request #44236 removes the content-length branch of request().

An ended response that a disconnect cuts. The raw client takes 65535 of 262140 bytes and closes the connection. For a response that the client reads in full, every runtime gives 'finish', writableFinished === true and rstCode 0.

	core `stream.end(body)`	compat `res.end(body)`
node v26.11.1	no `'aborted'`, `writableFinished` false, `rstCode` 8	`req.aborted` false, `res.writableFinished` false, `rstCode` 8
main	`'aborted'`, `writableFinished` false, `rstCode` 8	`req.aborted` true, `res.writableFinished` true, `rstCode` 8
this PR	no `'aborted'`, `writableFinished` false, `rstCode` 8	`req.aborted` false, `res.writableFinished` true, `rstCode` 8

Node v26.3.0 differs from v26.11.1 in one value: finished(stream) rejects with ERR_STREAM_PREMATURE_CLOSE (v26.11.1, main and this PR: it resolves).

A pushed stream that the client closes. A raw server promises stream 2 and starts its response. Events of the pushed stream and the RST_STREAM frames that the server gets:

call in `'stream'`	node v26.3.0, v26.11.1	main	this PR
`close(NGHTTP2_CANCEL)`	`close`. RST 8	`aborted`, `error` (`Invalid stream id`), no `close`. RST 8	`close`. RST 8
`close(NGHTTP2_REFUSED_STREAM)`	`error`, `close`. RST 7	`aborted`, `error` (`Invalid stream id`), no `close`. RST 7	`error`, `close`. RST 7
`close()`	`close`. RST 0	`aborted`, `error` (`Invalid stream id`), no `close`. No RST	`close`. No RST
`destroy()`	`close`. RST 0	`close`. No RST	`close`. No RST

The missing RST_STREAM(NO_ERROR) is the same as on main: native rstStream writes nothing for code 0 on an id that it does not know, and it does not know a pushed stream. For the same reason the session's count of open streams does not go down after these calls, so a later session.close() does not complete (main: the same, node: it completes). finished(pushed) rejects with ERR_STREAM_PREMATURE_CLOSE on main and here (node resolves), because the writable side is not ended at creation. #43534 registers the pushed stream natively and ends its writable side at creation. It then removes the pushed-stream check and this branch of close().

finished() and pipeline(). They reject when 'aborted' fires before the writable side finishes. Without the stray event the result follows the write.

After end(body) and signal.abort(), finished(req) rejects with ABORT_ERR, as in node (main: ERR_STREAM_PREMATURE_CLOSE). A test.
An ended stream that the peer resets with CANCEL, on a JS Duplex socket: Bun completes the dropped write, so the 12 rows (6 transports, finished() and pipeline()) go from ERR_STREAM_PREMATURE_CLOSE to success. Node v26.11.1 gives success on all 12, node v26.3.0 gives ERR_STREAM_PREMATURE_CLOSE.
The same on TCP and TLS sockets: the 14 rows keep ERR_STREAM_PREMATURE_CLOSE.

Clean path.

200 clean exchanges in each of 10 modes (GET, POST, 204, endStream, compat, HEAD, trailers, file, push), with main's http2.js and with this PR's on one debug binary: one helper call for each stream that is destroyed. process.nextTick, setImmediate, queueMicrotask and bind counts are equal to main in all 10.
Bytecode, release builds, 3 clean exchanges with BUN_JSC_dumpGeneratedBytecodes=1: 344 of 347 compiled functions are identical. _destroy 169 to 154 instructions. It runs 18 instructions to the branch on both sides, and the helper adds 5. abortIfWritableOpen is 36 instructions. request 943 to 958 (the three end() calls, not on the clean path). respond 370, end 86, _write 149, _final 215, not changed.
Bytes: size text of the release builds 89,151,860 to 89,153,055 (+1,195), of which http2.js +171 and native code +1,024. The last commit (pushed close()) adds 29 bytes to http2.js: the release bundler gives 168,942 for main and 169,142 for this PR.

Self-review. 34 concerns, 30 addressed. Not taken:

Sweep the server streams from JS on socket close. See "The native part".
Queue the close that respond() causes, to remove the Closed check. It adds a process.nextTick to every response with END_STREAM on its HEADERS frame, and Closed is node's own guard.
Pin finished() on a JS Duplex socket with a test. The two node versions differ there.
Todo tests for 'finish' after a dropped write. node:http2: fail a dropped write with ECANCELED, keep no write callback in native #44881 has those tests.

Earlier attempt. #33375 fixed the respond() case with a new status bit. The stale-PR cleanup closed it. This PR covers that case with the Closed check.

Test file. 52 cases. Node v26.3.0 and v26.11.1 pass 52. Main passes 18, fails 32, and 2 are todo. This PR passes 50, and 2 are todo. The tests use node:test and node:assert, so the same file runs under node: node --test test/js/node/http2/node-http2-aborted.test.ts. The todo cases run there.

Suites. Release builds of main and of this PR, 337 files: test/js/node/http2/ (12), the vendored *http2* tests in test/js/node/test/ (283), test/js/third_party/grpc-js/ (29), test/js/web/fetch/fetch-http2-* (3), 7 regression tests that use node:http2, AsyncLocalStorage.test.ts, socket-syscall-fault.test.ts and node-http2-ping-flood-staged.test.ts. The results are the same on both sides, except for the new file. grpc test-resolver and test-tonic fail on both sides (no DNS and no tonic server in the sandbox). Two test-client cases fail in 3 of 14 runs on both. Debug (ASAN) build of this PR: the new file and the 10 vendored tests that assert 'aborted' pass. test/js/node/http2/ gives no sanitizer report. In this container 15 of its slowest tests exceed the 5 s timeout on the debug binary. They pass with a longer timeout, except one reset-flood case that has a 10 s wait of its own.

[human-review] gate passed · iteration 0 · 3 files touched

fails on main (without fix)

ASAN without fix: 32 failed, 2 skipped
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" "test/js/node/http2/node-http2-aborted.test.ts"
bun test v1.4.4 (367d939d9)

test/js/node/http2/node-http2-aborted.test.ts:
(pass) ServerHttp2Stream 'aborted' > write(body), then RST_STREAM(CANCEL): emitted [1763.49ms]
264 |     test(`write(body), then ${how}: emitted`, async () => {
265 |       assert.deepStrictEqual(await leftAfterOneWindow(how, respondOpen), emitted);
266 |     });
267 | 
268 |     test(`end(body), then ${how}: not emitted`, async () => {
269 |       assert.deepStrictEqual(await leftAfterOneWindow(how, respondEnded), notEmitted);
                   ^
AssertionError: Expected values to be strictly deep-equal:
+ actual - expected

  {
+   aborted: true,
-   aborted: false,
    events: [
+     'aborted',
      'close'
    ]
  }

 generatedMessage: true,
     actual: {
  events: [Array ...],
  aborted: true,
},
   expected: {
  events: [Array ...],
  aborted: false,
},
   operator: "deepStrictEqual",
       diff: "simple",
       code: "ERR_ASSERTION"

      at /workspace/bun/test/js/node/http2/node-http2-aborted.test.ts
... (truncated)

release without fix: 32 failed, 2 skipped
bun test v1.4.3-canary.1 (367d939d9)

test/js/node/http2/node-http2-aborted.test.ts:
(pass) ServerHttp2Stream 'aborted' > write(body), then RST_STREAM(CANCEL): emitted [65.42ms]
264 |     test(`write(body), then ${how}: emitted`, async () => {
265 |       assert.deepStrictEqual(await leftAfterOneWindow(how, respondOpen), emitted);
266 |     });
267 | 
268 |     test(`end(body), then ${how}: not emitted`, async () => {
269 |       assert.deepStrictEqual(await leftAfterOneWindow(how, respondEnded), notEmitted);
                   ^
AssertionError: Expected values to be strictly deep-equal:
+ actual - expected

  {
+   aborted: true,
-   aborted: false,
    events: [
+     'aborted',
      'close'
    ]
  }

 generatedMessage: true,
     actual: {
  events: [Array ...],
  aborted: true,
},
   expected: {
  events: [Array ...],
  aborted: false,
},
   operator: "deepStrictEqual",
       diff: "simple",
       code: "ERR_ASSERTION"

      at /workspace/bun/test/js/node/http2/node-http2-aborted.test.ts:269:14
      at node:test:1445:26
      at executeTestNode (node:test:1448:63)
      at processTicksAndRejections (native:7:39)
(fail) ServerHttp2Stream 'aborted' > end(bod
... (truncated)

passes on PR (with fix)

ASAN with fix: 2 skipped
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" "test/js/node/http2/node-http2-aborted.test.ts"
bun test v1.4.4 (367d939d9)

test/js/node/http2/node-http2-aborted.test.ts:
(pass) ServerHttp2Stream 'aborted' > write(body), then RST_STREAM(CANCEL): emitted [1795.41ms]
(pass) ServerHttp2Stream 'aborted' > end(body), then RST_STREAM(CANCEL): not emitted [372.99ms]
(pass) ServerHttp2Stream 'aborted' > write(body), then GOAWAY(NO_ERROR) and FIN: emitted [223.96ms]
(pass) ServerHttp2Stream 'aborted' > end(body), then GOAWAY(NO_ERROR) and FIN: not emitted [222.50ms]
(pass) ServerHttp2Stream 'aborted' > write(body), then FIN: emitted [145.03ms]
(pass) ServerHttp2Stream 'aborted' > end(body), then FIN: not emitted [103.83ms]
(pass) ServerHttp2Stream 'aborted' > write(body), then RST_STREAM(CANCEL) over a Duplex: emitted [157.64ms]
(pass) ServerHttp2Stream 'aborted' > end(body), then RST_STREAM(CANCEL) over a Duplex: not emitted [77.20ms]
(pass) ServerHttp2Stream 'aborted' > write(body), then RST_STREAM(NO_ERROR): emitted [317.96ms]
(pass) ServerHttp2Stream 'aborted' > write(body) and end(), th
... (truncated)

release with fix: 2 skipped
$ bun scripts/build.ts --profile=release
[configured] bun-profile → bun (stripped)
  target       linux-x64-gnu
  build type   Release
  build dir    ./build/release
  revision     cc3e6d9ac8
  features     lto, baseline

23 deps, 146 codegen, 1176 objects in 1965ms

ninja: Entering directory `/workspace/bun/build/release'
[1/4] fetch lolhtml
[lolhtml] up to date
[2/4] fetch rust-argon2
[rust-argon2] up to date
[2/4] cargo plan → /workspace/bun/build/release/rust-target/plan.json
265 units: 193 lib, 16 proc-macro (host), 19 custom-build (host), 15 run custom-build, 17 lib (host), 4 run custom-build (host), 1 rlib
[3/4] reconfigure
[1/1530] mkdir codegen
[2/1530] mkdir stamps
[3/1530] gen bake.{client,server,error}.js
-> bake.client.js, bake.server.js, bake.error.js
[4/1530] install /workspace/bun
bun install v1.4.3-canary.1 (367d939d9)

Checked 22 installs across 44 packages (no changes) [1236.00ms]
[5/1530] install /workspace/bun/packages/bun-error
bun install v1.4.3-canary.1 (367d939d9)

Checked 1 install across 2 packages (no changes) [27.00ms]
[6/1530] rustc unicode_xid 
[7/1530] rustc unicode_ident 
[8/1530] gen string-map defines_table
[9/1530] rustc heck 
... (truncated)

diff hotspot

src/js/node/http2.ts                          |  60 +-
 src/runtime/api/bun/h2_frame_parser.rs        |  51 +-
 test/js/node/http2/node-http2-aborted.test.ts | 865 ++++++++++++++++++++++++++
 3 files changed, 930 insertions(+), 46 deletions(-)

gate history · 2 passed · 0 rejected · iteration 0

evidence per changed file

file                                           reads  edits  tests
src/js/node/http2.ts                              14      4    112
src/runtime/api/bun/h2_frame_parser.rs             7      0    114
test/js/node/http2/node-http2-aborted.test.ts      5      4    108

robobun · 2026-10-12T08:55:27Z

^{Updated 5:54 AM PT - Oct 14th, 2026}

✅ @robobun, your commit cc3e6d9ac89b028c46898022732f47dfbe11f1b2 passed in Build #125452! 🎉

🧪 To try this PR locally:

bunx bun-pr 45056

That installs a local version of the PR into your bun-45056 executable, so you can run:

bun-45056 --bun

coderabbitai · 2026-10-12T09:02:01Z

Walkthrough

HTTP/2 abort handling now uses a shared writable-state check and defers queued write callbacks until after abort dispatch. Selected rejected client requests end their returned streams. A new test suite checks abort events and flags across server, client, compatibility, and pushed streams.

Changes

HTTP/2 Abort Handling

Layer / File(s)	Summary
Parser abort dispatch and write callbacks `src/runtime/api/bun/h2_frame_parser.rs`	Abort paths collect queued write callbacks before stream cleanup, dispatch `onAborted` without the previous-state argument, and run the callbacks after dispatch.
Writable abort decisions `src/js/node/http2.ts`, `test/js/node/http2/node-http2-aborted.test.ts`	Stream close, destruction, and native abort callbacks use a shared check to decide whether to emit `aborted` and end the writable. Tests cover abort events and flags across server, compatibility, client, and pushed streams.
Ending rejected client requests `src/js/node/http2.ts`, `test/js/node/http2/node-http2-aborted.test.ts`	Selected rejected requests end when `endStream` is set. The forbidden-content-length rejection ends its returned request stream. Client tests cover abort scenarios, refused requests, and stream-ID exhaustion.

Suggested reviewers: jarred-sumner

Priority: ➖ Normal

Merge Risk: 🔵 Low · up to 98a7b

Applications relying on the writable finish event for pushed streams may miss it when a stream closes. The impact is narrow, but the lifecycle should be corrected before merge if compatibility is required.

Pre-merge checks: 4

Passed checks: 4 passed

Check name	Status	Explanation
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.
Title check		The title clearly and concisely describes the primary change: emitting the HTTP/2 'aborted' event only while the writable side is open.
Description check		The description is comprehensive and covers the problem, fix, scope, limitations, and verification results. It does not use the exact template headings, but it provides the required information, inclu…

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robobun · 2026-10-12T09:09:13Z

Status

How the problem was reproduced (release build of main at 6c1eb06, node v26.3.0 and v26.11.1 as the reference):

A node:http2 server reads a POST body to its end and calls stream.respond({ ":status": 204 }). Main emits 'aborted' on the server stream on 200 of 200 exchanges. Node emits none.
A server calls stream.end(body) with a body of four flow-control windows. A raw client takes one window, then sends RST_STREAM(CANCEL) or closes the socket. Main emits 'aborted'. Node emits none.
The new test file holds both cases and 50 more: bun bd test test/js/node/http2/node-http2-aborted.test.ts. Main fails 32 of the 52 cases. Node passes 52 with node --test on the same file.

PR: #45056

claude

Beyond the inline findings, two sibling 'aborted' sites were examined and ruled out: the local RST path in end_stream (h2_frame_parser.rs:2184) for a peer protocol error while an end()-calling write callback is queued, and a synchronous peer reset during end(chunk) over a JS Duplex socket — neither reproduced a divergence from node attributable to this change. dispatch_with_2_extra keeps other callers after the three onAborted sites moved to dispatch_with_extra, so no dead helper is left behind.

Extended reasoning...

The change reworks when node:http2 streams emit 'aborted' across src/js/node/http2.ts (new abortIfWritableOpen helper replacing three inlined blocks, plus request() early end() calls) and src/runtime/api/bun/h2_frame_parser.rs (dropped-write callbacks deferred until after the onAborted dispatch at three producers), with a new 834-line test file. It touches no auth, crypto, or injection surface. Six confirmed findings are posted inline, including pushed-stream close() no longer sending RST_STREAM and write(body, () => end()) losing 'aborted', so a human look is needed; this note only records the sibling sites that were checked and found unaffected.

Findings marked 🟡 are optional suggestions and need no follow-up push.

Additional findings (outside the current diff — GitHub can't attach inline comments there):

🟣 src/runtime/api/bun/h2_frame_parser.rs — Clients that call session.destroy() while a request body is flow-control queued and the write callback calls end() get no 'aborted' event on that stream, where node emits one. emit_error_to_all_streams at src/runtime/api/bun/h2_frame_parser.rs:6521 still runs free_resources, and with it the dropped write's callback, before the onStreamError dispatch at :6522, so _destroy sees ending === true. Fix: apply the same take_write_callbacks / run_write_callbacks reorder to this producer and to end_stream at :2184 so every path that drops queued writes decides 'aborted' before the callbacks run, not only the three onAborted sites.

Why this was flagged

A client writes a body larger than the peer's flow-control window with stream.write(body, () => stream.end()); send_data at src/runtime/api/bun/h2_frame_parser.rs:5290 queues the last frame with the callback. The app then calls session.destroy(). ClientHttp2Session.destroy at src/js/node/http2.ts:5918 calls parser.emitErrorToAllStreams; the loop at h2_frame_parser.rs:6521 calls free_resources, whose clean_queue (:1943) dispatches the callback, which calls end() and sets _writableState.ending. Only then does :6522 dispatch onStreamError, which destroys the stream and abortIfWritableOpen at http2.ts:2232 returns false. No 'aborted' is emitted; node emits 'aborted' because its callbacks run with an error after closeStream. The PR introduced take_write_callbacks and run_write_callbacks precisely for this ordering at :2149-2152 and :6478-6487 but left this sibling producer and end_stream (:2184) on the old order. The server path sweeps streams in JS first (http2.ts:4813) so only clients are hit, at the rate of any destroy() with a queued body.

Verification: Pre-existing; acknowledged in diff: the PR's own test file pins exactly this case as a todo at test/js/node/http2/node-http2-aborted.test.ts:640-647, and the note's bound is accurate. emit_error_to_all_streams (h2_frame_parser.rs:6516-6523) is untouched by the diff: it calls free_resources (:6521) before the onStreamError dispatch (:6522) with no take_write_callbacks/run_write_callbacks.

robobun · 2026-10-12T10:21:13Z

Reply to the review summary, for the finding outside the diff (emit_error_to_all_streams).

I tried that change on a scratch build. With take_write_callbacks and run_write_callbacks in emit_error_to_all_streams, the todo case write(body, () => end()), then session.destroy(): emitted still fails with { emitted: false, aborted: false }.

The streamError handlers do not decide. They queue emitStreamErrorNT with process.nextTick, and the rule runs in _destroy() on that tick.
emitErrorToAllStreams() is called from JS. The callbacks run when the native function returns, which is before that tick.
The case passes only when the two handlers also call abortIfWritableOpen() before they queue the tick. That moves 'aborted' one tick earlier for every stream error. Native request() can also call the handler before request() has ended a request without a body, so it needs a guard.

#42717 destroys the streams before the sweep, which fixes the order at its source. So this PR keeps the error sweep as it is, with the todo test and an entry under "Not changed" in the body. end_stream calls the same handlers.

One more change in 98a7b93, found while I checked the pushed-stream comments: the first commit sent two RST_STREAM frames for close(code) on a pushed stream. It sends one now, and a test counts the frames.

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Inline comments:
Review comments at @src/js/node/http2.ts:
- Line 2597: Update _final() to complete pushed streams without submitting an
empty DATA frame, and call end() after setting kPush on the pushed
ClientHttp2Stream so its writable side finishes before delivery. Preserve the
existing single-reset close path.

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src/js/node/http2.ts
test/js/node/http2/node-http2-aborted.test.ts

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abortIfWritableOpen() holds the 'aborted' rule of node's closeStream(). The two native aborted handlers, close() and _destroy() call it, before they end the readable side. It reads the writable state, not the state of the wire, and it knows the states where node has ended the writable side and Bun has not: a closed stream, a pending 'wantTrailers', a pushed stream on the client, the server stream of a HEAD request. request() ends a request without a body before it rejects it. close() on a pushed client stream destroys the stream. The native abort producers run the callbacks of dropped writes after the abort dispatch, so a callback that calls end() does not hide the abort.

close() on a pushed stream now leaves the reset to _destroy(). The stream has no native entry that removes a second reset, so close(code) followed by the destroy sent RST_STREAM two times. The test counts the RST_STREAM frames that a raw server gets.

robobun · 2026-10-18T05:58:53Z

A note on the order with #44881, which changes the same two handlers.

node:http2: fail a dropped write with ECANCELED, keep no write callback in native #44881 no longer changes when 'aborted' fires. Its earlier head had a second copy of the rule (!stream._writableState.ending in both aborted handlers). The current head (a06ea38) removed it, so this PR is the only owner of the rule.
The two PRs still conflict in src/js/node/http2.ts and src/runtime/api/bun/h2_frame_parser.rs. node:http2: fail a dropped write with ECANCELED, keep no write callback in native #44881 wraps the stream.emit("aborted") of both handlers in try / finally, and it takes the write callback out of native.
After node:http2: fail a dropped write with ECANCELED, keep no write callback in native #44881 native holds no write callback, so take_write_callbacks and run_write_callbacks have nothing to call. The PR that merges second drops them and keeps abortIfWritableOpen().

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robobun added 2 commits October 14, 2026 11:34

robobun force-pushed the robobun/d71e8e4d/http2-aborted-after-end branch from 98a7b93 to cc3e6d9 Compare October 14, 2026 12:22

This was referenced Oct 19, 2026

node:http2: do not start the readable when END_STREAM comes on a HEADERS frame #46121

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node:http2: close a client's open requests like node on session.destroy() #43591

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node:http2: drop DATA that arrives after close(code) ended the readable #46428

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Jarred-Sumner mentioned this pull request Oct 22, 2026

http: consolidate the open fetch, Bun.serve, node:http, node:http2 and HTTP/3 pull requests #46528

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node:http2: emit 'aborted' only while the writable side is open - #45056

node:http2: emit 'aborted' only while the writable side is open#45056
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