1819-remove-presence-lists.md

Remove references to presence lists

Presence lists allow a given user the ability to subscribe to other users and be alerted to their current presence status.

While spec'd, no established client has implemented support and the only server side implementation raises privacy concerns.

The proposal is to simply remove references to presence lists with a view to revisiting the same ideas in the future.

This MSC addresses #1810

Proposal

Presence lists seem like a good fit for 'MSC1769: Extensible profiles as rooms' proposal, meaning that the current design will most likely be superseded.

Additionally, no major client has implemented the behaviour to date and the only server implementation of presence lists (Synapse) auto-accepts invites leading to privacy concerns in the wild.

With this in mind the most pragmatic solution is to remove presence lists ahead of the r0 release.

Specifically:-

CS API: Remove

• POST /_matrix/client/r0/presence/list/{userId}
• GET /_matrix/client/r0/presence/list/{userId}

SS API: Remove

• m.presence_invite
• m.presence_accept
• m.presence_deny

Tradeoffs

Ideally this proposal would also come with an alternative design for this functionality. Out of pragmatism the proposal only covers removal of what is there today.

Conclusions

This is a common sense attempt to remove unused portions of the spec ahead of an r0 release. It does not suggest that the ability to subscribe to the presence of others is undesirable and assumes that this behaviour will return again in some form.