Spec currently_active time and idle timeout behaviour

specification/modules/presence.rst

@@ -20,7 +20,7 @@ membership of a room.
 A presence list is a list of user IDs whose presence the user wants to follow.
 To be added to this list, the user being added must be invited by the list owner
 who must accept the invitation.
- 
+
 User's presence state is represented by the ``presence`` key, which is an enum
 of one of the following:
 
@@ -30,8 +30,6 @@ of one of the following:
   idle.
 - ``offline`` : The user is not connected to an event stream or is
   explicitly suppressing their profile information from being sent.
-- ``free_for_chat`` : The user is generally willing to receive messages
-  moreso than default.
 
 Events
 ------
@@ -46,67 +44,44 @@ listed below.
 
 {{presence_http_api}}
 
-Idle timeout
-~~~~~~~~~~~~
-
-Clients SHOULD implement an "idle timeout". This is a timer which fires after
-a period of inactivity on the client. The definition of inactivity varies
-depending on the client. For example, web implementations may determine
-inactivity to be not moving the mouse for a certain period of time. When this
-timer fires it should set the presence state to ``unavailable``. When the user
-becomes active again (e.g. by moving the mouse) the client should set the
-presence state to ``online``. A timeout value between 1 and 5 minutes is
-recommended. 
-
 Server behaviour
 ----------------
 
 Each user's homeserver stores a "presence list" per user. Once a user accepts
 a presence list, both user's HSes must track the subscription.
 
-Propagating profile information
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Because the profile display name and avatar information are likely to be used in
-many places of a client's display, changes to these fields SHOULD cause an
-automatic propagation event to occur, informing likely-interested parties of the
-new values. One of these change mechanisms SHOULD be via ``m.presence`` events.
-These events should set ``displayname`` and ``avatar_url`` to the new values
-along with the presence-specific keys. This SHOULD be done automatically by the
-homeserver when a user successfully changes their display name or avatar URL.
-
-.. admonition:: Rationale
-
-  The intention for sending this information in ``m.presence`` is so that any
-  "user list" can display the *current* name/presence for a user ID outside the
-  scope of a room e.g. for a user page. This is bundled into a single event for
-  several reasons. The user's display name can change per room. This
-  event provides the "canonical" name for the user. In addition, the name is
-  bundled into a single event for the ease of client implementations. If this
-  was not done, the client would need to search all rooms for their own
-  membership event to pull out the display name.
-
-
 Last active ago
 ~~~~~~~~~~~~~~~
-The server maintains a timestamp of the last time it saw a
+The server maintains a timestamp of the last time it saw a pro-active event from
-pro-active event from the user. A pro-active event may be sending a message to a
+the user. A pro-active event may be sending a message to a room or changing
-room or changing presence state to a higher level of availability. Levels of
+presence state to ``online``. This timestamp is presented via a key called
-availability are defined from low to high as follows:
+``last_active_ago`` which gives the relative number of milliseconds since the
+pro-active event.
+
+To reduce the number of presence updates sent to clients the server may include
+a ``currently_active`` boolean field when the presence state is ``online``. When
+true, the server will not send further updates to the last active time until an
+update is sent to the client with either a) ``currently_active`` set to false or
+b) a presence state other than ``online``. During this period clients must
+consider the user to be currently active, irrespective of the last active time.
+
+The last active time must be up to date whenever the server gives a presence
+event to the client; the ``currently_active`` mechanism should purely be used to
+disable as opposed to disabling last active tracking. Thus clients can fetch up
+to date last active times by explicitly requesting the presence for a given
+user.
 
-- ``offline``
+Idle timeout
-- ``unavailable``
+~~~~~~~~~~~~
-- ``online``
-- ``free_for_chat``
 
-Based on this list, changing state from ``unavailable`` to ``online`` counts as
+The server will automatically set a users presence to ``unavailable`` if their
-a pro-active event, whereas ``online`` to ``unavailable`` does not. This
+last active time was over 5 minutes ago. Clients can manually set a users
-timestamp is presented via a key called ``last_active_ago`` which gives the
+presence to ``unavailable``. Any activity that bumps the last active time on any
-relative number of milliseconds since the pro-active event.
+of the user's clients will cause the server to automatically set their presence
+to ``online``.
 
 Security considerations
 -----------------------
-    
+
 Presence information is shared with all users who share a room with the target
 user. In large public rooms this could be undesirable.
-