MUC: allow emitting muc#roominfo_webchat_url disco#info form extension field

[horazont]

The muc#roominfo_webchat_url disco#info extension form field allows to publish a URL to a webchat which allows to join the room anonymously. It would be good if ejabberd supported emitting this URL.

I’ll leave the implementation details up to you. Options which come to mind:

1. A domain-wide URL template (configured by the admin) where ejabberd substitutes placeholders like {jid} when generating the reply form (similar to how Prosody implements this).
2. A MUC configuration form option for users to fill in manually.
3. A combination of (1) and (2), where (1) is the default if the user has not set the option explicitly.

It might be desirable to have an room-level opt-out for this.

Additional context

• The search engine https://search.jabber.network will add the link to the result page if it is present in the room info
• Prosody supports this in the mod_muc_webchat_url extension
• There is a pull request against XEP-0045 to standardise the muc#roominfo_webchat_url field.
• Example: the MUC xsf@muc.xmpp.org advertises the form field.

[badlop]

I wonder how much interest is there nowadays in this feature

[horazont]

@badlop Look at the number of rooms with a "Join using browser" button on https://search.jabber.network . That button uses the muc#roominfo_webchat_url disco#info form field.