Add MembershipChanges to send presence down /sync

syncapi/streams/stream_pdu.go

@@ -185,7 +185,6 @@ func (p *PDUStreamProvider) IncrementalSync(
 		// If this room was joined in this sync, try to fetch
 		// as much timeline events as allowed by the filter.
 		if delta.NewlyJoined {
-			req.NewlyJoined[delta.RoomID] = struct{}{}
 			// Reverse the range, so we get the most recent first.
 			// This will be limited by the eventFilter.
 			newRange = types.Range{
@@ -195,7 +194,7 @@ func (p *PDUStreamProvider) IncrementalSync(
 			}
 		}
 		var pos types.StreamPosition
-		if pos, err = p.addRoomDeltaToResponse(ctx, snapshot, req.Device, newRange, delta, &eventFilter, &stateFilter, req.Response); err != nil {
+		if pos, err = p.addRoomDeltaToResponse(ctx, snapshot, req.Device, newRange, delta, &eventFilter, &stateFilter, req); err != nil {
 			req.Log.WithError(err).Error("d.addRoomDeltaToResponse failed")
 			if err == context.DeadlineExceeded || err == context.Canceled || err == sql.ErrTxDone {
 				return newPos
@@ -226,7 +225,7 @@ func (p *PDUStreamProvider) addRoomDeltaToResponse(
 	delta types.StateDelta,
 	eventFilter *gomatrixserverlib.RoomEventFilter,
 	stateFilter *gomatrixserverlib.StateFilter,
-	res *types.Response,
+	req *types.SyncRequest,
 ) (types.StreamPosition, error) {
 	if delta.MembershipPos > 0 && delta.Membership == gomatrixserverlib.Leave {
 		// make sure we don't leak recent events after the leave event.
@@ -291,8 +290,10 @@ func (p *PDUStreamProvider) addRoomDeltaToResponse(
 	hasMembershipChange := false
 	for _, recentEvent := range recentStreamEvents {
 		if recentEvent.Type() == gomatrixserverlib.MRoomMember && recentEvent.StateKey() != nil {
+			if membership, _ := recentEvent.Membership(); membership == gomatrixserverlib.Join {
+				req.MembershipChanges[*recentEvent.StateKey()] = struct{}{}
+			}
 			hasMembershipChange = true
-			break
 		}
 	}
 
@@ -321,7 +322,7 @@ func (p *PDUStreamProvider) addRoomDeltaToResponse(
 		// didn't "remove" events, return that the response is limited.
 		jr.Timeline.Limited = (limited && len(events) == len(recentEvents)) || delta.NewlyJoined
 		jr.State.Events = gomatrixserverlib.HeaderedToClientEvents(delta.StateEvents, gomatrixserverlib.FormatSync)
-		res.Rooms.Join[delta.RoomID] = jr
+		req.Response.Rooms.Join[delta.RoomID] = jr
 
 	case gomatrixserverlib.Peek:
 		jr := types.NewJoinResponse()
@@ -330,7 +331,7 @@ func (p *PDUStreamProvider) addRoomDeltaToResponse(
 		jr.Timeline.Events = gomatrixserverlib.HeaderedToClientEvents(recentEvents, gomatrixserverlib.FormatSync)
 		jr.Timeline.Limited = limited
 		jr.State.Events = gomatrixserverlib.HeaderedToClientEvents(delta.StateEvents, gomatrixserverlib.FormatSync)
-		res.Rooms.Peek[delta.RoomID] = jr
+		req.Response.Rooms.Peek[delta.RoomID] = jr
 
 	case gomatrixserverlib.Leave:
 		fallthrough // transitions to leave are the same as ban
@@ -343,7 +344,7 @@ func (p *PDUStreamProvider) addRoomDeltaToResponse(
 		// didn't "remove" events, return that the response is limited.
 		lr.Timeline.Limited = limited && len(events) == len(recentEvents)
 		lr.State.Events = gomatrixserverlib.HeaderedToClientEvents(delta.StateEvents, gomatrixserverlib.FormatSync)
-		res.Rooms.Leave[delta.RoomID] = lr
+		req.Response.Rooms.Leave[delta.RoomID] = lr
 	}
 
 	return latestPosition, nil

syncapi/streams/stream_presence.go

@@ -20,6 +20,7 @@ import (
 	"sync"
 
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/tidwall/gjson"
 
 	"github.com/matrix-org/dendrite/syncapi/notifier"
 	"github.com/matrix-org/dendrite/syncapi/storage"
@@ -69,19 +70,20 @@ func (p *PresenceStreamProvider) IncrementalSync(
 		return from
 	}
 
-	// add newly joined rooms user presences
-	if len(req.NewlyJoined) > 0 {
-		newlyJoinedRoomIDs := make([]string, 0, len(req.NewlyJoined))
-		for roomID := range req.NewlyJoined {
-			newlyJoinedRoomIDs = append(newlyJoinedRoomIDs, roomID)
+	if len(presences) == 0 {
+		return to
 	}
+
+	// add newly joined rooms user presences
+	newlyJoined := joinedRooms(req.Response, req.Device.UserID)
+	if len(newlyJoined) > 0 {
 		// TODO: Check if this is working better than before.
-		if err = p.notifier.LoadRooms(ctx, p.DB, newlyJoinedRoomIDs); err != nil {
+		if err = p.notifier.LoadRooms(ctx, p.DB, newlyJoined); err != nil {
 			req.Log.WithError(err).Error("unable to refresh notifier lists")
 			return from
 		}
 	NewlyJoinedLoop:
-		for _, roomID := range newlyJoinedRoomIDs {
+		for _, roomID := range newlyJoined {
 			roomUsers := p.notifier.JoinedUsers(roomID)
 			for i := range roomUsers {
 				// we already got a presence from this user
@@ -101,8 +103,6 @@ func (p *PresenceStreamProvider) IncrementalSync(
 				}
 			}
 		}
-	} else {
-		return to
 	}
 
 	lastPos := from
@@ -121,7 +121,8 @@ func (p *PresenceStreamProvider) IncrementalSync(
 			prevPresence := pres.(*types.PresenceInternal)
 			currentlyActive := prevPresence.CurrentlyActive()
 			skip := prevPresence.Equals(presence) && currentlyActive && req.Device.UserID != presence.UserID
-			if skip {
+			_, membershipChange := req.MembershipChanges[presence.UserID]
+			if skip && !membershipChange {
 				req.Log.Tracef("Skipping presence, no change (%s)", presence.UserID)
 				continue
 			}
@@ -162,3 +163,36 @@ func (p *PresenceStreamProvider) IncrementalSync(
 
 	return lastPos
 }
+
+func joinedRooms(res *types.Response, userID string) []string {
+	var roomIDs []string
+	for roomID, join := range res.Rooms.Join {
+		// we would expect to see our join event somewhere if we newly joined the room.
+		// Normal events get put in the join section so it's not enough to know the room ID is present in 'join'.
+		newlyJoined := membershipEventPresent(join.State.Events, userID)
+		if newlyJoined {
+			roomIDs = append(roomIDs, roomID)
+			continue
+		}
+		newlyJoined = membershipEventPresent(join.Timeline.Events, userID)
+		if newlyJoined {
+			roomIDs = append(roomIDs, roomID)
+		}
+	}
+	return roomIDs
+}
+
+func membershipEventPresent(events []gomatrixserverlib.ClientEvent, userID string) bool {
+	for _, ev := range events {
+		// it's enough to know that we have our member event here, don't need to check membership content
+		// as it's implied by being in the respective section of the sync response.
+		if ev.Type == gomatrixserverlib.MRoomMember && ev.StateKey != nil && *ev.StateKey == userID {
+			// ignore e.g. join -> join changes
+			if gjson.GetBytes(ev.Unsigned, "prev_content.membership").Str == gjson.GetBytes(ev.Content, "membership").Str {
+				continue
+			}
+			return true
+		}
+	}
+	return false
+}

syncapi/sync/request.go

@@ -100,6 +100,7 @@ func newSyncRequest(req *http.Request, device userapi.Device, syncDB storage.Dat
 		Timeout:           timeout,                   //
 		Rooms:             make(map[string]string),   // Populated by the PDU stream
 		WantFullState:     wantFullState,             //
+		MembershipChanges: make(map[string]struct{}), // Populated by the PDU stream
 	}, nil
 }
 

syncapi/types/provider.go

@@ -23,7 +23,7 @@ type SyncRequest struct {
 	// Updated by the PDU stream.
 	Rooms map[string]string
 	// Updated by the PDU stream.
-	NewlyJoined map[string]struct{}
+	MembershipChanges map[string]struct{}
 	// Updated by the PDU stream.
 	IgnoredUsers IgnoredUsers
 }