PeerTube cannot follow PeerTube instances using an Internationalized Domain Name (IDN)

[pietsch]

Describe the current behavior

I want my instance to follow the PeerTube instance tube.bawü.social. When I click the Follow button and paste this hostname into the text area, I get the error message Hosts or handles are invalid. tube.bawü.social is not valid., and the submit button is greyed out.

As you can see, there is an ü umlaut in its domain name. This is called an Internationalized Domain Name (IDN).

Workaround: Currently, to follow an instance that uses an IDN, users have to find out the corresponding Punycode or ACE string (in this case: tube.xn--baw-joa.social) and enter that instead.

Recommendation: This conversion should be done by PeerTube. There are Ruby libraries for this task.

Steps to reproduce

1. Go to /admin/follows/following-list on your PeerTube instance.
2. Click the Follow button.
3. Enter a PeerTube hostname containing an IDN, e.g. tube.bawü.social.

Describe the expected behavior

I should now be able to submit this form by clicking the other Follow button below.

IDNs should be accepted and automatically converted if necessary.

Additional information

• PeerTube instance: digitalcourage.video

  • URL: https://digitalcourage.video/
  • Version: 4.2.2
  • NodeJS version: v14.20.0
  • Ffmpeg version: 4.1.9-0+deb10u1

• Browser name, version and platforms on which you could reproduce the bug: Firefox 102.0.1 on Debian GNU/Linux

[Axeltherabbit]

I have also noticed looking at the source code that no host validation is done if a handle is provided, so peertube@tube.bawü.social is "fine" but obviously fails when it sends the request