Added presence update on change of profile information and config flags for selective presence tracking

changelog.d/16992.feature

@@ -0,0 +1 @@
+Added presence tracking of user profile updates and config flags for disabling user activity tracking. Contributed by @Michael-Hollister.

docs/usage/configuration/config_documentation.md

@@ -247,6 +247,8 @@ Example configuration:
 presence:
   enabled: false
   include_offline_users_on_sync: false
+  local_activity_tracking: true
+  remote_activity_tracking: true
 ```
 
 `enabled` can also be set to a special value of "untracked" which ignores updates
@@ -259,6 +261,21 @@ When clients perform an initial or `full_state` sync, presence results for offli
 not included by default. Setting `include_offline_users_on_sync` to `true` will always include
 offline users in the results. Defaults to false.
 
+Enabling presence tracking can be resource intensive for the presence handler when server-side
+tracking of user activity is enabled. Below are some additional configuration options which may
+help improve the performance of the presence feature without outright disabling it:
+* `local_activity_tracking` (Default enabled): Determines if the server tracks a user's activity
+when syncing or fetching events. If disabled, the server will not automatically update the
+user's presence activity when the /sync or /events endpoints are called. Note that client
+applications can still update their presence by calling the presence /status endpoint.
+* `remote_activity_tracking` (Default enabled): Determines if the server will accept presence
+EDUs from remote servers that are exclusively user activity updates. If disabled, the server
+will reject processing these EDUs. However if a presence EDU contains profile updates to any of
+the `status_msg`, `displayname`, or `avatar_url` fields, then the server will accept the EDU.
+
+If the presence `enabled` field is set to "untracked", then these options will both act as if
+set to false.
+
 ---
 ### `require_auth_for_profile_requests`
 
@@ -1765,7 +1782,7 @@ rc_3pid_validation:
 
 This option sets ratelimiting how often invites can be sent in a room or to a
 specific user. `per_room` defaults to `per_second: 0.3`, `burst_count: 10`,
-`per_user` defaults to `per_second: 0.003`, `burst_count: 5`, and `per_issuer` 
+`per_user` defaults to `per_second: 0.003`, `burst_count: 5`, and `per_issuer`
 defaults to `per_second: 0.3`, `burst_count: 10`.
 
 Client requests that invite user(s) when [creating a
@@ -1966,7 +1983,7 @@ max_image_pixels: 35M
 ---
 ### `remote_media_download_burst_count`
 
-Remote media downloads are ratelimited using a [leaky bucket algorithm](https://en.wikipedia.org/wiki/Leaky_bucket), where a given "bucket" is keyed to the IP address of the requester when requesting remote media downloads. This configuration option sets the size of the bucket against which the size in bytes of downloads are penalized - if the bucket is full, ie a given number of bytes have already been downloaded, further downloads will be denied until the bucket drains.  Defaults to 500MiB. See also `remote_media_download_per_second` which determines the rate at which the "bucket" is emptied and thus has available space to authorize new requests.  
+Remote media downloads are ratelimited using a [leaky bucket algorithm](https://en.wikipedia.org/wiki/Leaky_bucket), where a given "bucket" is keyed to the IP address of the requester when requesting remote media downloads. This configuration option sets the size of the bucket against which the size in bytes of downloads are penalized - if the bucket is full, ie a given number of bytes have already been downloaded, further downloads will be denied until the bucket drains.  Defaults to 500MiB. See also `remote_media_download_per_second` which determines the rate at which the "bucket" is emptied and thus has available space to authorize new requests.
 
 Example configuration:
 ```yaml

synapse/api/presence.py

@@ -83,6 +83,8 @@ class UserPresenceState:
     last_user_sync_ts: int
     status_msg: Optional[str]
     currently_active: bool
+    displayname: Optional[str]
+    avatar_url: Optional[str]
 
     def as_dict(self) -> JsonDict:
         return attr.asdict(self)
@@ -101,4 +103,6 @@ def default(cls, user_id: str) -> "UserPresenceState":
             last_user_sync_ts=0,
             status_msg=None,
             currently_active=False,
+            displayname=None,
+            avatar_url=None,
         )

synapse/config/server.py

@@ -389,6 +389,16 @@ def read_config(self, config: JsonDict, **kwargs: Any) -> None:
             "include_offline_users_on_sync", False
         )
 
+        # Disabling server-side presence tracking
+        self.presence_local_activity_tracking = presence_config.get(
+            "local_activity_tracking", True
+        )
+
+        # Disabling federation presence tracking
+        self.presence_remote_activity_tracking = presence_config.get(
+            "remote_activity_tracking", True
+        )
+
         # Custom presence router module
         # This is the legacy way of configuring it (the config should now be put in the modules section)
         self.presence_router_module_class = None

synapse/federation/federation_server.py

@@ -1425,9 +1425,30 @@ def register_instances_for_edu(
         self._edu_type_to_instance[edu_type] = instance_names
 
     async def on_edu(self, edu_type: str, origin: str, content: dict) -> None:
+        """Passes an EDU to a registered handler if one exists
+
+        This potentially modifies the `content` dict for `m.presence` EDUs when
+        presence `remote_activity_tracking` is disabled.
+
+        Args:
+            edu_type: The type of the incoming EDU to process
+            origin: The server we received the event from
+            content: The content of the EDU
+        """
         if not self.config.server.track_presence and edu_type == EduTypes.PRESENCE:
             return
 
+        if (
+            not self.config.server.presence_remote_activity_tracking
+            and edu_type == EduTypes.PRESENCE
+        ):
+            filtered_edus = []
+            for e in content["push"]:
+                # Process only profile presence updates to reduce resource impact
+                if "status_msg" in e or "displayname" in e or "avatar_url" in e:
+                    filtered_edus.append(e)
+            content["push"] = filtered_edus
+
         # Check if we have a handler on this instance
         handler = self.edu_handlers.get(edu_type)
         if handler:

synapse/handlers/presence.py

@@ -201,6 +201,9 @@ def __init__(self, hs: "HomeServer"):
 
         self._presence_enabled = hs.config.server.presence_enabled
         self._track_presence = hs.config.server.track_presence
+        self._presence_local_activity_tracking = (
+            hs.config.server.presence_local_activity_tracking
+        )
 
         self._federation = None
         if hs.should_send_federation():
@@ -451,6 +454,8 @@ async def send_full_presence_to_users(self, user_ids: StrCollection) -> None:
         state = {
             "presence": current_presence_state.state,
             "status_message": current_presence_state.status_msg,
+            "displayname": current_presence_state.displayname,
+            "avatar_url": current_presence_state.avatar_url,
         }
 
         # Copy the presence state to the tip of the presence stream.
@@ -579,7 +584,11 @@ async def user_syncing(
         Called by the sync and events servlets to record that a user has connected to
         this worker and is waiting for some events.
         """
-        if not affect_presence or not self._track_presence:
+        if (
+            not affect_presence
+            or not self._track_presence
+            or not self._presence_local_activity_tracking
+        ):
             return _NullContextManager()
 
         # Note that this causes last_active_ts to be incremented which is not
@@ -648,6 +657,8 @@ async def process_replication_rows(
                 row.last_user_sync_ts,
                 row.status_msg,
                 row.currently_active,
+                row.displayname,
+                row.avatar_url,
             )
             for row in rows
         ]
@@ -1140,7 +1151,11 @@ async def user_syncing(
                 client that is being used by a user.
             presence_state: The presence state indicated in the sync request
         """
-        if not affect_presence or not self._track_presence:
+        if (
+            not affect_presence
+            or not self._track_presence
+            or not self._presence_local_activity_tracking
+        ):
             return _NullContextManager()
 
         curr_sync = self._user_device_to_num_current_syncs.get((user_id, device_id), 0)
@@ -1340,6 +1355,8 @@ async def incoming_presence(self, origin: str, content: JsonDict) -> None:
 
             new_fields["status_msg"] = push.get("status_msg", None)
             new_fields["currently_active"] = push.get("currently_active", False)
+            new_fields["displayname"] = push.get("displayname", None)
+            new_fields["avatar_url"] = push.get("avatar_url", None)
 
             prev_state = await self.current_state_for_user(user_id)
             updates.append(prev_state.copy_and_replace(**new_fields))
@@ -1369,6 +1386,8 @@ async def set_state(
                 the `state` dict.
         """
         status_msg = state.get("status_msg", None)
+        displayname = state.get("displayname", None)
+        avatar_url = state.get("avatar_url", None)
         presence = state["presence"]
 
         if presence not in self.VALID_PRESENCE:
@@ -1414,6 +1433,8 @@ async def set_state(
         else:
             # Syncs do not override the status message.
             new_fields["status_msg"] = status_msg
+            new_fields["displayname"] = displayname
+            new_fields["avatar_url"] = avatar_url
 
         await self._update_states(
             [prev_state.copy_and_replace(**new_fields)], force_notify=force_notify
@@ -1634,6 +1655,8 @@ async def _handle_state_delta(self, room_id: str, deltas: List[StateDelta]) -> N
                 if state.state != PresenceState.OFFLINE
                 or now - state.last_active_ts < 7 * 24 * 60 * 60 * 1000
                 or state.status_msg is not None
+                or state.displayname is not None
+                or state.avatar_url is not None
             ]
 
             await self._federation_queue.send_presence_to_destinations(
@@ -1668,6 +1691,14 @@ def should_notify(
         notify_reason_counter.labels(user_location, "status_msg_change").inc()
         return True
 
+    if old_state.displayname != new_state.displayname:
+        notify_reason_counter.labels(user_location, "displayname_change").inc()
+        return True
+
+    if old_state.avatar_url != new_state.avatar_url:
+        notify_reason_counter.labels(user_location, "avatar_url_change").inc()
+        return True
+
     if old_state.state != new_state.state:
         notify_reason_counter.labels(user_location, "state_change").inc()
         state_transition_counter.labels(
@@ -1725,6 +1756,8 @@ def format_user_presence_state(
             * status_msg: Optional. Included if `status_msg` is set on `state`. The user's
                 status.
             * currently_active: Optional. Included only if `state.state` is "online".
+            * displayname: Optional. The current display name for this user, if any.
+            * avatar_url: Optional. The current avatar URL for this user, if any.
 
         Example:
 
@@ -1733,7 +1766,9 @@ def format_user_presence_state(
             "user_id": "@alice:example.com",
             "last_active_ago": 16783813918,
             "status_msg": "Hello world!",
-            "currently_active": True
+            "currently_active": True,
+            "displayname": "Alice",
+            "avatar_url": "mxc://localhost/wefuiwegh8742w"
         }
     """
     content: JsonDict = {"presence": state.state}
@@ -1745,6 +1780,10 @@ def format_user_presence_state(
         content["status_msg"] = state.status_msg
     if state.state == PresenceState.ONLINE:
         content["currently_active"] = state.currently_active
+    if state.displayname:
+        content["displayname"] = state.displayname
+    if state.avatar_url:
+        content["avatar_url"] = state.avatar_url
 
     return content
 

synapse/handlers/profile.py

@@ -202,6 +202,19 @@ async def set_displayname(
         if propagate:
             await self._update_join_states(requester, target_user)
 
+        if self.hs.config.server.track_presence:
+            presence_handler = self.hs.get_presence_handler()
+            current_presence_state = await presence_handler.get_state(target_user)
+
+            state = {
+                "presence": current_presence_state.state,
+                "status_message": current_presence_state.status_msg,
+                "displayname": new_displayname,
+                "avatar_url": current_presence_state.avatar_url,
+            }
+
+            await presence_handler.set_state(target_user, requester.device_id, state)
+
     async def get_avatar_url(self, target_user: UserID) -> Optional[str]:
         if self.hs.is_mine(target_user):
             try:
@@ -295,6 +308,19 @@ async def set_avatar_url(
         if propagate:
             await self._update_join_states(requester, target_user)
 
+        if self.hs.config.server.track_presence:
+            presence_handler = self.hs.get_presence_handler()
+            current_presence_state = await presence_handler.get_state(target_user)
+
+            state = {
+                "presence": current_presence_state.state,
+                "status_message": current_presence_state.status_msg,
+                "displayname": current_presence_state.displayname,
+                "avatar_url": new_avatar_url,
+            }
+
+            await presence_handler.set_state(target_user, requester.device_id, state)
+
     @cached()
     async def check_avatar_size_and_mime_type(self, mxc: str) -> bool:
         """Check that the size and content type of the avatar at the given MXC URI are

synapse/replication/tcp/streams/_base.py

@@ -330,6 +330,8 @@ class PresenceStreamRow:
         last_user_sync_ts: int
         status_msg: str
         currently_active: bool
+        displayname: str
+        avatar_url: str
 
     NAME = "presence"
     ROW_TYPE = PresenceStreamRow