feat(sliding-sync): tie presence extension into sendPresence setting

Author: Evie Gauthier

src/app/features/settings/general/General.tsx

@@ -410,6 +410,7 @@ function Editor({ isMobile }: { isMobile: boolean }) {
   const [isMarkdown, setIsMarkdown] = useSetting(settingsAtom, 'isMarkdown');
   const [hideActivity, setHideActivity] = useSetting(settingsAtom, 'hideActivity');
   const [hideReads, setHideReads] = useSetting(settingsAtom, 'hideReads');
+  const [sendPresence, setSendPresence] = useSetting(settingsAtom, 'sendPresence');
 
   return (
     <Box direction="Column" gap="100">
@@ -453,6 +454,13 @@ function Editor({ isMobile }: { isMobile: boolean }) {
           after={<Switch variant="Primary" value={hideReads} onChange={setHideReads} />}
         />
       </SequenceCard>
+      <SequenceCard className={SequenceCardStyle} variant="SurfaceVariant" direction="Column">
+        <SettingTile
+          title="Presence Status"
+          description="Show and receive online status from other users."
+          after={<Switch variant="Primary" value={sendPresence} onChange={setSendPresence} />}
+        />
+      </SequenceCard>
     </Box>
   );
 }

src/app/pages/client/ClientNonUIFeatures.tsx

@@ -38,6 +38,7 @@ import {
 } from '$utils/notificationStyle';
 import { mobileOrTablet } from '$utils/user-agent';
 import { useSlidingSyncActiveRoom } from '$hooks/useSlidingSyncActiveRoom';
+import { getSlidingSyncManager } from '$client/initMatrix';
 import { getInboxInvitesPath } from '../pathUtils';
 import { BackgroundNotifications } from './BackgroundNotifications';
 
@@ -580,6 +581,17 @@ function SlidingSyncActiveRoomSubscriber() {
   return null;
 }
 
+function PresenceFeature() {
+  const mx = useMatrixClient();
+  const [sendPresence] = useSetting(settingsAtom, 'sendPresence');
+
+  useEffect(() => {
+    getSlidingSyncManager(mx)?.setPresenceEnabled(sendPresence);
+  }, [mx, sendPresence]);
+
+  return null;
+}
+
 export function ClientNonUIFeatures({ children }: ClientNonUIFeaturesProps) {
   return (
     <>
@@ -592,6 +604,7 @@ export function ClientNonUIFeatures({ children }: ClientNonUIFeaturesProps) {
       <BackgroundNotifications />
       <SyncNotificationSettingsWithServiceWorker />
       <SlidingSyncActiveRoomSubscriber />
+      <PresenceFeature />
       {children}
     </>
   );

src/app/state/settings.ts

@@ -78,6 +78,7 @@ export interface Settings {
   captionPosition: CaptionPosition;
 
   // Sable features!
+  sendPresence: boolean;
   mobileGestures: boolean;
   rightSwipeAction: RightSwipeAction;
   hideMembershipInReadOnly: boolean;
@@ -153,6 +154,7 @@ const defaultSettings: Settings = {
   captionPosition: CaptionPosition.Below,
 
   // Sable features!
+  sendPresence: true,
   mobileGestures: true,
   rightSwipeAction: RightSwipeAction.Reply,
   hideMembershipInReadOnly: true,

src/client/slidingSync.ts

@@ -241,8 +241,14 @@ const getListEndIndex = (list: MSC3575List | null): number => {
 // poll and feeds received `m.presence` events into the SDK's User objects so that
 // components using `useUserPresence` see live updates (same path as regular /sync).
 class ExtensionPresence implements Extension<{ enabled: boolean }, { events?: object[] }> {
+  private enabled = true;
+
   public constructor(private readonly mx: MatrixClient) {}
 
+  public setEnabled(value: boolean): void {
+    this.enabled = value;
+  }
+
   public name(): string {
     return 'presence';
   }
@@ -253,7 +259,7 @@ class ExtensionPresence implements Extension<{ enabled: boolean }, { events?: ob
   }
 
   public async onRequest(_isInitial: boolean): Promise<{ enabled: boolean }> {
-    return { enabled: true };
+    return { enabled: this.enabled };
   }
 
   public async onResponse(data: { events?: object[] }): Promise<void> {
@@ -297,6 +303,8 @@ export class SlidingSyncManager {
 
   private readonly onLifecycle: (state: SlidingSyncState, resp: unknown, err?: Error) => void;
 
+  private presenceExtension!: ExtensionPresence;
+
   public readonly slidingSync: SlidingSync;
 
   public readonly probeTimeoutMs: number;
@@ -329,7 +337,8 @@ export class SlidingSyncManager {
 
     // Register the presence extension so m.presence events from the server are fed
     // into the SDK's User objects, keeping useUserPresence accurate during sliding sync.
-    this.slidingSync.registerExtension(new ExtensionPresence(mx));
+    this.presenceExtension = new ExtensionPresence(mx);
+    this.slidingSync.registerExtension(this.presenceExtension);
 
     // Register a custom subscription for unencrypted active rooms; encrypted rooms use
     // the default subscription (which already has [*,*]).
@@ -406,6 +415,10 @@ export class SlidingSyncManager {
     );
   }
 
+  public setPresenceEnabled(enabled: boolean): void {
+    this.presenceExtension.setEnabled(enabled);
+  }
+
   public getDiagnostics(): SlidingSyncDiagnostics {
     return {
       proxyBaseUrl: this.proxyBaseUrl,