matrix-spec-proposals/specification/modules/dm.rst

.. Copyright 2016 OpenMarket Ltd
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.. Licensed under the Apache License, Version 2.0 (the "License");
.. you may not use this file except in compliance with the License.
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..     http://www.apache.org/licenses/LICENSE-2.0
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Direct Messaging
================

.. _module:dm:

All communication over Matrix happens within a room. It is sometimes
desirable to offer users the concept of speaking directly to one
particular person. This module defines a way of marking certain rooms
as 'direct chats' with a given person. This does not restrict the chat
to being between exactly two people since this would preclude the
presence of automated 'bot' users or even a 'personal assistant' who is
able to answer direct messages on behalf of the user in their absence.

A room may not necessarily be considered 'direct' by all members of the
room, but a signalling mechanism exists to propagate the information of
whether a chat is 'direct' to an invitee.

Events
------

{{m_direct_event}}

Client behaviour
----------------
The invitee's client may use the ``is_direct`` flag in the `m.room.member`_
event to automatically mark the room as a direct message but this is not
required: it may for example, prompt the user, ignore the flag altogether. To
do this, it stores this event in account data using the
|/user/<user_id>/account_data/<type>|_ API.

The inviter's client should set the ``is_direct`` flag to |/createRoom|_
whenever the flow the user has followed is one where their
intention is to speak directly with another person, as opposed to bringing that
person in to a shared room. For example, clicking on, 'Start Chat' beside a
person's profile picture would imply the ``is_direct`` flag should be set.

Server behaviour
----------------
When the ``is_direct`` flag is given to |/createRoom|_, the home
server must set the ``is_direct`` flag in the invite member event for any users
invited in the |/createRoom|_ call.