backfill: serialize history sync portal flag updates

pkg/connector/backfill.go

@@ -96,6 +96,16 @@ func (wa *WhatsAppClient) historySyncLoop(ctx context.Context) {
 		}
 		if resetTimer {
 			timerPending.Store(true)
+			wa.historySyncPortalLock.Lock()
+			wa.historySyncPortalGen++
+			if meta := wa.UserLogin.Metadata.(*waid.UserLoginMetadata); !meta.HistorySyncPortalsNeedCreating {
+				meta.HistorySyncPortalsNeedCreating = true
+				err := wa.UserLogin.Save(ctx)
+				if err != nil {
+					wa.UserLogin.Log.Err(err).Msg("Failed to save user login history sync portals need creating flag")
+				}
+			}
+			wa.historySyncPortalLock.Unlock()
 		}
 		if timerPending.Load() {
 			dispatchTimer.Reset(wa.Main.Config.HistorySync.DispatchWait)
@@ -417,6 +427,9 @@ func (wa *WhatsAppClient) createPortalsFromHistorySync(ctx context.Context) {
 		}
 	}()
 	ctx = log.WithContext(ctx)
+	wa.historySyncPortalLock.Lock()
+	gen := wa.historySyncPortalGen
+	wa.historySyncPortalLock.Unlock()
 	limit := wa.Main.Config.HistorySync.MaxInitialConversations
 	loginTS := wa.UserLogin.Metadata.(*waid.UserLoginMetadata).LoggedInAt
 	conversations, err := wa.Main.DB.Conversation.GetRecent(ctx, wa.UserLogin.ID, limit, loginTS)
@@ -517,6 +530,11 @@ func (wa *WhatsAppClient) createPortalsFromHistorySync(ctx context.Context) {
 	log.Info().Int("conversation_count", len(conversations)).Msg("Finished creating portals from history sync")
 	go func() {
 		wg.Wait()
+		wa.historySyncPortalLock.Lock()
+		defer wa.historySyncPortalLock.Unlock()
+		if wa.historySyncPortalGen != gen {
+			return
+		}
 		wa.UserLogin.Metadata.(*waid.UserLoginMetadata).HistorySyncPortalsNeedCreating = false
 		err = wa.UserLogin.Save(ctx)
 		if err != nil {

pkg/connector/client.go

@@ -128,6 +128,9 @@ type WhatsAppClient struct {
 	lastPresence       types.Presence
 	blocklistLock      sync.Mutex
 
+	historySyncPortalLock sync.Mutex
+	historySyncPortalGen  uint64
+
 	disableNewsletter bool
 
 	appStateRecoveryLock      sync.Mutex