server: read the method id uWS resolved, not the method name by robobun · Pull Request #45399 · oven-sh/bun

robobun · 2026-10-15T20:23:06Z

Problem

A route handler asks uWS for the method name and looks it up in METHOD_MAP. 12 readers handle a failed lookup. 10 of them substitute GET, POST or OPTIONS (RequestContext.rs:1426, DevServer.rs:1774).
With Bun.serve: answer 501 to an unknown method and 404 to a router miss, not a closed socket #45396 and Bun.serve http3: 501 or 400 before the router for a request line the HTTP/2 listener refuses #45357 no handler runs for a name that is not in the map, so the arms cannot run.

Fix

Request::method() returns a Method. The shim asks uWS for the id of the method (uws_req_get_method_id).
The 12 arms go, and the Option<Method> parameters with them. So do Method::find(), RouteMethod::specific() and the string fallback in NodeHTTP.cpp.
An id that is no Method fails a debug assertion. A release build reads it as GET, as before.
Self-reviewed: 33 concerns raised, 32 addressed (Bun.serve: answer 501 to an unknown method and 404 to a router miss, not a closed socket #45396).

Behaviour change: none

Tests that cover this code: test/js/bun/http/bun-serve-routes.test.ts (each of the 36 methods must arrive as req.method), test/js/node/http/node-http.test.ts, test/js/bun/http/serve-http2.test.ts, test/js/bun/http/serve-http3.test.ts, test/js/bun/http/bun-serve-file.test.ts.

Background

methodIdFromWire() (uws: resolve a request method to its id inline #44510) maps a method name to the discriminant of Method.
Each transport answers a method with no id before a handler: 501 on HTTP/1.1 (Bun.serve: answer 501 to an unknown method and 404 to a router miss, not a closed socket #45396), HTTP/2 (Bun.serve http2: reject the request bytes the HTTP/1 parser rejects #40676) and HTTP/3 (Bun.serve http3: 501 or 400 before the router for a request line the HTTP/2 listener refuses #45357), 400 from the node:http parser.
Considered an unchecked conversion of the id. Method::from_repr costs one compare.

Downsides

Draft until Bun.serve http3: 501 or 400 before the router for a request line the HTTP/2 listener refuses #45357 lands. Without its HTTP/3 check an unknown :method reaches a handler: a debug build fails the assertion, and PatCh arrives as GET, not PATCH.
Per request: the shim resolves the id (17 instructions for GET), and Method::which (22 for GET) goes. Release binary: 8,704 bytes smaller.

Notes

The 12 arms: RequestContext.rs:1426, StaticRoute.rs:292, FileRoute.rs:233, DirectoryRoute.rs:107 and DevServer.rs:2129 (GET). DevServer.rs:1774 and :2099 (POST). mod.rs:758, server_body.rs:2904 and NodeHTTPResponse.rs:2751 (OPTIONS, for the body length). mod.rs:1315 passed undefined to C++, which then made a string from the name (NodeHTTP.cpp:96). HTMLBundle.rs:276 answered 405.
Four functions lose their method parameter and read it from the request: prepare_js_request_context, prepare_js_request_context_for, prepare_and_save_js_request_context and upgrade_web_socket_user_route. RequestContext::create and create_in take a Method.
RouteMethod::specific() gave the method of a route to its handler. It was always the method of the request: the HEAD that Bun derives from a GET route is registered as a HEAD route.
Why no handler runs for a request without an id: the Bun.serve HTTP/1.1 dispatch answers 501 first (Bun.serve: answer 501 to an unknown method and 404 to a router miss, not a closed socket #45396), HTTP/2 does since Bun.serve http2: reject the request bytes the HTTP/1 parser rejects #40676, HTTP/3 does with Bun.serve http3: 501 or 400 before the router for a request line the HTTP/2 listener refuses #45357, and the parser of the node:http instantiation answers 400 (Bun.serve: answer 501 to an unknown method and 404 to a router miss, not a closed socket #45396 made that check part of the instantiation).
This PR is a draft until Bun.serve http3: 501 or 400 before the router for a request line the HTTP/2 listener refuses #45357 lands. On HTTP/3 main lowercases the method for the lookup, so PatCh arrives as PATCH and BREW as GET. With this PR and no HTTP/3 check both arrive as GET in a release build, and a debug build fails the assertion.
Before it leaves draft this branch needs a rebase: bake: move the code into folders by job (no behavior change) #45489 moved DevServer.rs into dev_server/, and three of the removed arms are there.
Open question before this PR leaves draft: the first ask of Custom HTTP methods via Bun.serve() #6556, a method outside the 36 that reaches fetch. fetch, Request, server.fetch: stop sending GET for a method outside the method table #44718 (open) lets a Request carry any method token. This PR and uws: key HttpRouter by method id #45400 remove the method name from the path between uWS and Rust, so a request with no method id has no name to deliver. If maintainers want such a request delivered, the name must stay readable for it. That needs a maintainer decision.
A release build reads an id that is no Method as GET. That is what each of the 10 arms did. uws: key HttpRouter by method id #45400 makes the router refuse such an id, and then Request::method() asserts it in release builds too.
Instructions per request. In uWS (standalone driver over the real HttpParser.h and HttpRouter.h, clang -O3, qemu-x86_64 -one-insn-per-tb -d exec,nochain), node:http: keep the method of a dispatched request as sent in 'clientError' rawPacket #45398 then this PR: GET 2395, 2412. POST 2697, 2710. The 17 and 13 more are methodIdFromWire() in the shim. In Rust, Method::which goes: 31 instructions per call for GET and 30 for POST in a loop whose empty body costs 9 and 5 (cargo build --release of an example that calls it, same counter). The slice that the old shim returned goes too and is not counted.
Instructions per request end to end: not measured. perf is not available in the build container (perf_event_paranoid is 4), and valgrind is not installed.
sizeof: no struct changes.
Release binary (llvm-size): text 80,701,779 -> 80,693,075 bytes (node:http: keep the method of a dispatched request as sent in 'clientError' rawPacket #45398, then this PR, on base f4d755a; measured before the two id getters moved into this PR). data and bss do not change.
Suites (debug build with ASAN). On this PR: bun-serve-routes (86 tests), node-http-pipeline-callbacks, node-http, serve-http2, serve-http2-protocol, serve-http3, bun-serve-static, bun-serve-file, serve-directory-routes, bun-serve-html. On uws: key HttpRouter by method id #45400, which has this change: also node-http-displaced-response, request-smuggling, three test-http-*-client-error Node tests, and serve.test.ts.

robobun · 2026-10-15T20:27:24Z

Status

This PR changes no behaviour once #45357 is in. It is a draft until then. #45396 has the reproduction of the bug that this stack fixes.

The stack: #44510, #45396, #45397, #45398, #45399 (draft), #45400 (draft).

Request::method() returns the Method for the id that the parser stored on the request. A handler runs only for a request that has one, so the 12 lookups that substituted GET, POST or OPTIONS for a name they did not know go, with the Option<Method> parameters that carried a second copy of the method.

github-actions Bot added the claude label Oct 15, 2026

robobun force-pushed the robobun/5627effc/node-http-rawpacket-method branch from c2b76a4 to de273e4 Compare October 15, 2026 20:32

robobun force-pushed the robobun/5627effc/serve-method-id-rust branch from 45d2e2c to 9e5913c Compare October 15, 2026 20:32

robobun force-pushed the robobun/5627effc/node-http-rawpacket-method branch from de273e4 to 8b4be0f Compare October 15, 2026 21:45

robobun force-pushed the robobun/5627effc/serve-method-id-rust branch from 9e5913c to ed1a9e9 Compare October 15, 2026 21:57

robobun force-pushed the robobun/5627effc/node-http-rawpacket-method branch 3 times, most recently from 84f2a1d to c5d8886 Compare October 17, 2026 10:06

robobun force-pushed the robobun/5627effc/serve-method-id-rust branch from ed1a9e9 to 41e84b1 Compare October 17, 2026 10:06

robobun force-pushed the robobun/5627effc/serve-method-id-rust branch from 41e84b1 to 6005a00 Compare October 17, 2026 11:03

robobun force-pushed the robobun/5627effc/node-http-rawpacket-method branch from c5d8886 to 5c34108 Compare October 17, 2026 11:03

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

Open

Navigation Menu

Repository navigation

server: read the method id uWS resolved, not the method name - #45399

server: read the method id uWS resolved, not the method name#45399
robobun wants to merge 1 commit into
robobun/5627effc/node-http-rawpacket-methodfrom
robobun/5627effc/serve-method-id-rust

robobun commented Oct 15, 2026 •

edited

Loading

Uh oh!

robobun commented Oct 15, 2026

Uh oh!

This branch has not been deployed

Reviewers

Uh oh!

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

Conversation

robobun commented Oct 15, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Problem

Fix

Background

Downsides

Uh oh!

robobun commented Oct 15, 2026

Uh oh!

This branch has not been deployed

Reviewers

Uh oh!

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

robobun commented Oct 15, 2026 •

edited

Loading