fix: already in use port #10638

[Scttpr]

Description

This PR is solving issue 10638.

After a short investigation, recent NodeJS versions will not detect running processes on 0.0.0.0:<desired_port> if the provided host is localhost but it will if hostname resolves to 127.0.0.1.

This PR is just changing the default secure hostname from localhost to 127.0.0.1 without changing anything about custom name resolved by #8647.

Additional context

---

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the Commit Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it. -> It passes anyway but I updated unit tests

[sapphi-red]

Thanks for the PR.

But I'm afraid this will change the behavior when

• DNS resolves localhost to ::1
• and either
  • using Node.js 17+ and not setting dns.setDefaultResultOrder('ipv4first')
  • using Node.js 17< and setting dns.setDefaultResultOrder('verbatim')

. In that situation, Vite will now listen to 127.0.0.1 instead of ::1. This is a breaking change.

Also I don't think behaving differently from Node.js's default is a good thing. And this is the problem we had in Vite 2.

I think we can just check whether 0.0.0.0:port is occupied rather than changing the default host to listen.

[Scttpr]

Thanks for the PR.

But I'm afraid this will change the behavior when

* DNS resolves `localhost` to `::1`

* and either
  
  * using Node.js 17+ and not setting `dns.setDefaultResultOrder('ipv4first')`
  * using Node.js 17< and setting `dns.setDefaultResultOrder('verbatim')`

. In that situation, Vite will now listen to 127.0.0.1 instead of ::1. This is a breaking change.

Also I don't think behaving differently from Node.js's default is a good thing. And this is the problem we had in Vite 2.

I think we can just check whether 0.0.0.0:port is occupied rather than changing the default host to listen.

Agreed, if I get it right, the last commit is a proposal I'm not very proud of but it works :/ What do you think ?

[thomasballinger]

(thanks for doing this work!)

I'm worried actually opening on 0.0.0.0 might trip firewalls, if an OS were set up to allow listening on localhost but not external ports. But I haven't seen this.

[sapphi-red]

I think we should listen to 0.0.0.0 first and then listen to the specified host to avoid other process to listen to that port between switching the host.

Also I guess we need to check 0.0.0.0 for hosts other than localhost too.

[vlmlee]

Hi sapphi-red, I have a fix for your suggestion here: Scttpr#3 I am unsure how I should move forward with this

[Scttpr]

There was an update but I have checked, it is possible to have an ipv6 and an ipv4 process running on the same port. Node looks to respect this behavior thus I'm not sure this check is needed finally.