res.writableFinished o res.writableEnded never become true when using finished

[bjohansebas]

Version

22.14.0 and probably previous versions

Platform

Linux bjohansebas 6.14.2-arch1-1 #1 SMP PREEMPT_DYNAMIC Thu, 10 Apr 2025 18:43:59 +0000 x86_64 GNU/Linux

Subsystem

http, stream

What steps will reproduce the bug?

When using finished, res.writableEnded, or res.writableFinished, it never becomes true

const http = require('http')
const net = require('net')
const finished = require('stream').finished
const assert = require('assert')

var server = http.createServer(function (req, res) {
  finished(res, function (err) {
    assert.ok(err)
    assert.ok(res.writableFinished)
    assert.ok(res.writableEnded)
    server.close(function () {})
  })
  
  socket.on('error', function () {})
  socket.write('W')
})

let socket

server.listen(function () {
  socket = net.connect(this.address().port, function () {
    writeRequest(this, true)
  })
})

function writeRequest (socket, chunked) {
  socket.write('GET / HTTP/1.1\r\n')
  socket.write('Host: localhost\r\n')
  socket.write('Connection: keep-alive\r\n')

  if (chunked) {
    socket.write('Transfer-Encoding: chunked\r\n')
  }

  socket.write('\r\n')
}

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

Always

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

should return true

What do you see instead?

false

Additional information

This is part of the tests for on-finished (https://github.com/jshttp/on-finished/blob/f8b5f4097d28df79e466d1ffdf58ccb27d769156/test/test.js#L368-L387)

I might be using the wrong properties to determine when the request has finished, so i understand this might not be a bug

[bjohansebas]

cc: @nodejs/streams @nodejs/http

[climba03003]

You are inspecting the response, but you are actually reaching error (Premature close) in your example.
So, the response is never ended properly and write any data.

res.writableEnded will becomes true when response.end is called.
res.writableFinished will becomes true when all the data is flush to the socket.
Both condition is not fulfill in your example.

[bjohansebas]

Okay, I understand. So this issue is more like a feature request. onFinished does the following check: socket && !socket.writable, which is an important validation to determine if writing can continue, and is important for body-parser and other Express middlewares. It may be that 'finished' isn’t the right term and something else is needed, but I’d say it would be good to implement it in the core and leave on-finished aside.