Only set currently_active if online

Avoid unneeded presence updates when syncing

clientapi/routing/presence.go

@@ -124,10 +124,11 @@ func GetPresence(
 	}
 
 	lastActiveTS := gomatrixserverlib.Timestamp(lastActive)
+	currentlyActive := time.Since(lastActiveTS.Time()).Minutes() < 5
 	return util.JSONResponse{
 		Code: http.StatusOK,
 		JSON: types.PresenceClientResponse{
-			CurrentlyActive: time.Since(lastActiveTS.Time()).Minutes() < 5,
+			CurrentlyActive: &currentlyActive,
 			LastActiveAgo:   time.Since(lastActiveTS.Time()).Milliseconds(),
 			Presence:        presence.Header.Get("presence"),
 			StatusMsg:       &statusMsg,

syncapi/streams/stream_presence.go

@@ -18,6 +18,7 @@ import (
 	"context"
 	"database/sql"
 	"encoding/json"
+	"sync"
 	"time"
 
 	"github.com/matrix-org/dendrite/syncapi/types"
@@ -26,6 +27,7 @@ import (
 
 type PresenceStreamProvider struct {
 	StreamProvider
+	cache sync.Map
 }
 
 func (p *PresenceStreamProvider) Setup() {
@@ -64,6 +66,7 @@ func (p *PresenceStreamProvider) IncrementalSync(
 	rooms, err := p.DB.AllJoinedUsersInRooms(ctx)
 	if err != nil {
 		req.Log.WithError(err).Error("unable to query joined users")
+		return from
 	}
 
 	sharedUsers := map[string]bool{
@@ -88,11 +91,11 @@ func (p *PresenceStreamProvider) IncrementalSync(
 			}
 			presences[roomUsers[i]], err = p.DB.GetPresence(ctx, roomUsers[i])
 			if err != nil {
-				req.Log.WithError(err).Error("unable to query presence for user")
+				req.Log.WithError(err).Warn("unable to query presence for user")
 				if err == sql.ErrNoRows {
 					continue
 				}
-				return to
+				return from
 			}
 		}
 	}
@@ -104,8 +107,24 @@ func (p *PresenceStreamProvider) IncrementalSync(
 		if !sharedUsers[presence.UserID] {
 			continue
 		}
+		pres, ok := p.cache.Load(req.Device.UserID + presence.UserID)
+		if ok {
+			// skip already sent presence
+			prevPresence := pres.(*types.Presence)
+			currentlyActive := time.Since(prevPresence.LastActiveTS.Time()).Minutes() < 5
+			samePresence := prevPresence.ClientFields.Presence == presence.ClientFields.Presence &&
+				prevPresence.ClientFields.StatusMsg == presence.ClientFields.StatusMsg
+			skip := currentlyActive && samePresence && req.Device.UserID != presence.UserID
+			if skip {
+				req.Log.Debugf("Skipping presence, no change (%s)", presence.UserID)
+				continue
+			}
+		}
 		presence.ClientFields.LastActiveAgo = time.Since(presence.LastActiveTS.Time()).Milliseconds()
-		presence.ClientFields.CurrentlyActive = time.Since(presence.LastActiveTS.Time()).Minutes() < 5
+		currentlyActive := time.Since(presence.LastActiveTS.Time()).Minutes() < 5
+		if presence.ClientFields.Presence == "online" {
+			presence.ClientFields.CurrentlyActive = &currentlyActive
+		}
 
 		content, err := json.Marshal(presence.ClientFields)
 		if err != nil {
@@ -120,6 +139,7 @@ func (p *PresenceStreamProvider) IncrementalSync(
 		if presence.StreamPos > lastPos {
 			lastPos = presence.StreamPos
 		}
+		p.cache.Store(req.Device.UserID+presence.UserID, presence)
 	}
 
 	return lastPos

syncapi/types/types.go

@@ -522,7 +522,7 @@ type Presence struct {
 }
 
 type PresenceClientResponse struct {
-	CurrentlyActive bool    `json:"currently_active"`
+	CurrentlyActive *bool   `json:"currently_active,omitempty"`
 	LastActiveAgo   int64   `json:"last_active_ago,omitempty"`
 	Presence        string  `json:"presence"`
 	StatusMsg       *string `json:"status_msg,omitempty"`