http: `HEAD` request consumes response body

[LiviaMedeiros]

Version

v22.10.0

Platform

Linux tumba 6.12.6-gentoo-yuran #1 SMP Sat Dec 21 16:28:04 +08 2024 x86_64 Intel(R) Core(TM)2 Quad CPU Q8200 @ 2.33GHz GenuineIntel GNU/Linux

Subsystem

http

What steps will reproduce the bug?

// srv.mjs
import { createServer } from 'node:http';
import { Readable } from 'node:stream';
const stream = Readable.from(['Hello ', 'World', '\n']);
stream.on('end', () => console.log('Body consumed'));
const server = createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  stream.pipe(res);
});
server.listen(9999, '127.0.0.9');

$ node srv.mjs

$ curl -I http://127.0.0.9:9999/
$ curl -v http://127.0.0.9:9999/

How often does it reproduce? Is there a required condition?

Always.

What is the expected behavior? Why is that the expected behavior?

No console output on server side after:

$ curl -I http://127.0.0.9:9999
HTTP/1.1 200 OK
Content-Type: text/plain
Date: Wed, 22 Jan 2025 12:34:56 GMT
Connection: keep-alive
Keep-Alive: timeout=5

Body consumed output on server side after:

$ curl http://127.0.0.9:9999
Hello World

What do you see instead?

Body consumed on server terminal after sending HEAD request.
Nothing on client terminal after sending subsequent GET request.

Additional information

With a patch from #56681, the body is correctly recognized as stream, resulting in Transfer-Encoding: chunked header in first response. However, the body is still slurped, and subsequent requests have zero length.

[xt-riot]

You are declaring the stream at the script start. It's only declared once, and once consumed it doesn't restart. According to node:

The 'end' event is emitted when there is no more data to be consumed from the stream.

Therefore, the subsequent request has no more data to read/pipe.

import { createServer } from 'node:http';
import { Readable } from 'node:stream';

const server = createServer((req, res) => {
  const stream = Readable.from(['Hello ', 'World', '\n']);
  stream.on('end', () => console.log('Body consumed'));
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  stream.pipe(res);
});
server.listen(9999, '127.0.0.9');

would fix that