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fix(frontend): skip short browser resumes and soften message refreshes #1345

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72 changes: 72 additions & 0 deletions apps/frontend/src/lib/hooks/useMayHaveMissedMessagesCallback.svelte.spec.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,10 @@ vi.mock('$lib/state/server/connection.svelte', () => ({
useConnection: () => () => ({ reconnectCount: 0 })
}));

vi.mock('$lib/hooks/useReconnectCallback.svelte', () => ({
useReconnectCallback: () => undefined
}));

class FakeServerConnection {
reconnectCount = $state(0);
realtimeUrl = 'ws://test-server/api/realtime';
Expand All @@ -33,11 +37,20 @@ class FakeServerConnection {

const TEST_SERVER = 'test-server';

function setVisibilityState(value: DocumentVisibilityState): void {
Object.defineProperty(document, 'visibilityState', {
value,
configurable: true
});
document.dispatchEvent(new Event('visibilitychange'));
}

describe('useMayHaveMissedMessagesCallback', () => {
let consoleDebug: ReturnType<typeof vi.spyOn>;

beforeEach(() => {
mocks.activeServerId = TEST_SERVER;
setVisibilityState('visible');
setRealtimeSocketFactoryForTests(() => ({
binaryType: 'arraybuffer',
readyState: 0,
Expand All @@ -52,6 +65,7 @@ describe('useMayHaveMissedMessagesCallback', () => {
});

afterEach(() => {
setVisibilityState('visible');
vi.useRealTimers();
eventBusManager.stopBus(TEST_SERVER);
setRealtimeSocketFactoryForTests(null);
Expand Down Expand Up @@ -88,6 +102,64 @@ describe('useMayHaveMissedMessagesCallback', () => {
rendered.unmount();
});

it('skips short browser visibility resumes', async () => {
vi.useFakeTimers();
const onSignal = vi.fn().mockResolvedValue(undefined);

const rendered = render(Harness, { props: { onSignal } });
flushSync();

setVisibilityState('hidden');
await vi.advanceTimersByTimeAsync(1_449);
setVisibilityState('visible');
await vi.advanceTimersByTimeAsync(1_000);

expect(onSignal).not.toHaveBeenCalled();
rendered.unmount();
});

it('skips short browser pageshow resumes with known hidden duration', async () => {
vi.useFakeTimers();
const onSignal = vi.fn().mockResolvedValue(undefined);

const rendered = render(Harness, { props: { onSignal } });
flushSync();

setVisibilityState('hidden');
await vi.advanceTimersByTimeAsync(1_449);
setVisibilityState('visible');
window.dispatchEvent(new Event('pageshow'));
await vi.advanceTimersByTimeAsync(1_000);

expect(onSignal).not.toHaveBeenCalled();
rendered.unmount();
});

it('runs the callback for longer browser visibility resumes', async () => {
vi.useFakeTimers();
const onSignal = vi.fn().mockResolvedValue(undefined);

const rendered = render(Harness, { props: { onSignal } });
flushSync();

setVisibilityState('hidden');
await vi.advanceTimersByTimeAsync(30_000);
setVisibilityState('visible');
await vi.advanceTimersByTimeAsync(1_000);

expect(onSignal).toHaveBeenCalledOnce();
expect(onSignal).toHaveBeenCalledWith(
expect.objectContaining({
serverId: TEST_SERVER,
reason: 'visibility',
phase: 'immediate',
source: 'browser',
hiddenDurationMs: 30_000
})
);
rendered.unmount();
});

it('coalesces a browser wake burst into one signal', async () => {
vi.useFakeTimers();
const onSignal = vi.fn().mockResolvedValue(undefined);
Expand Down
14 changes: 14 additions & 0 deletions apps/frontend/src/lib/hooks/useMayHaveMissedMessagesCallback.svelte.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -21,11 +21,21 @@ export type MayHaveMissedMessagesReason =
| 'manual-shortcut';

const DEDUPE_MS = 1_000;
const SHORT_BROWSER_RESUME_SKIP_MS = 30_000;

function isEventBusReason(reason: MayHaveMissedMessagesReason): boolean {
return reason.startsWith('event-bus-');
}

function shouldSkipShortBrowserResume(signal: ResumeSignal): boolean {
return (
signal.source === 'browser' &&
(signal.reason === 'visibility' || signal.reason === 'pageshow') &&
signal.hiddenDurationMs !== null &&
signal.hiddenDurationMs < SHORT_BROWSER_RESUME_SKIP_MS
);
}

function isEditableTarget(target: EventTarget | null): boolean {
if (!(target instanceof HTMLElement)) return false;
const tagName = target.tagName.toLowerCase();
Expand Down Expand Up @@ -89,6 +99,10 @@ function createRefreshRunner(
return {
trigger(signal: ResumeSignal): void {
const now = Date.now();
if (shouldSkipShortBrowserResume(signal)) {
console.debug('[room-refresh] skipped short browser resume signal', signal);
return;
}
if (inFlight) {
queuedSignal = signal;
console.debug('[room-refresh] queued maybe-missed signal while refresh is running', signal);
Expand Down
62 changes: 62 additions & 0 deletions apps/frontend/src/lib/state/room/messages.svelte.spec.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1009,6 +1009,68 @@ describe('MessagesStore — room lifecycle ownership', () => {
store.dispose();
});

it('soft-refreshes the latest room window without collapsing already-loaded history', async () => {
const initialLatest = Array.from({ length: 50 }, (_, index) =>
threadMessageEvent(`m${index + 51}`)
);
const older = Array.from({ length: 50 }, (_, index) => threadMessageEvent(`m${index + 1}`));
const refreshedLatest = Array.from({ length: 100 }, (_, index) => {
const id = `m${index + 2}`;
return id === 'm90' ? messageWithReaction(id, 'thumbsup') : threadMessageEvent(id);
});
const fake = new FakeQueryClient([
roomEventsResult({
events: initialLatest,
startCursor: 'tl:cursor-51',
endCursor: 'tl:cursor-100',
hasOlder: true,
hasNewer: false
}),
roomEventsResult({
events: older,
startCursor: 'tl:cursor-1',
endCursor: 'tl:cursor-50',
hasOlder: false,
hasNewer: true
}),
roomEventsResult({
events: refreshedLatest,
startCursor: 'tl:cursor-2',
endCursor: 'tl:cursor-101',
hasOlder: true,
hasNewer: false
})
]);
const store = new MessagesStore(
fake as unknown as ServerConnection,
() => null,
timelineFromFixtures(fake)
);

store.setRoom('room-1');
await settle();
await store.loadMore();
await settle();
expect(store.rootEvents).toHaveLength(100);
fake.queryMock.mockClear();

await store.refreshCurrentWindow();
await settle();

expect(store.isInitialLoading).toBe(false);
expect(store.rootEvents.map((event) => event.id)).toEqual(
Array.from({ length: 101 }, (_, index) => `m${index + 1}`)
);
expect(store.rootEvents.find((event) => event.id === 'm90')?.event).toMatchObject({
reactions: [{ emoji: 'thumbsup', count: 1 }]
});
expect(store.hasReachedStart).toBe(true);
expect(fake.queryMock).toHaveBeenCalledOnce();
expect(fake.queryMock.mock.calls[0][1]).toEqual({ roomId: 'room-1', limit: 100 });
expect(fake.queryMock.mock.calls[0][2]).toEqual({ requestPolicy: 'network-only' });
store.dispose();
});

it('soft-refreshes around an anchor event when one is provided', async () => {
const fake = new FakeQueryClient([
roomEventsResult({
Expand Down
44 changes: 30 additions & 14 deletions apps/frontend/src/lib/state/room/messages/MessagesStore.svelte.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -11,6 +11,7 @@ import { isRootRoomEvent, isThreadEvent } from './filters';
import { type EventConnectionPage, type RawEvent, getActorId, unmask } from './helpers';

type MessageScope = 'room' | 'thread';
type SnapshotCursorMode = 'replace' | 'preserve' | 'latest';
type RoomEventPayload = NonNullable<RoomEventView['event']>;
type MessagePostedPayload = Extract<RoomEventPayload, { kind: typeof RoomEventKind.MessagePosted }>;
type MessageEditedPayload = Extract<RoomEventPayload, { kind: typeof RoomEventKind.MessageEdited }>;
Expand All @@ -33,6 +34,8 @@ export type RefreshCurrentWindowResult = {
refreshed: boolean;
};

const MAX_SOFT_REFRESH_PAGE_SIZE = 500;

function eventCacheKey(roomId: string, eventId: string): string {
return `${roomId}\u0000${eventId}`;
}
Expand Down Expand Up @@ -240,6 +243,10 @@ export class MessagesStore {
return this.#loadId !== thisLoad;
}

private softRefreshLimit(): number {
return Math.min(Math.max(PAGE_SIZE, this.events.length), MAX_SOFT_REFRESH_PAGE_SIZE);
}

private previewKey(eventId: string): string {
return eventCacheKey(this.roomId, eventId);
}
Expand Down Expand Up @@ -888,14 +895,15 @@ export class MessagesStore {
hasOlder?: boolean;
},
existingBeforeFetch: ReadonlySet<string>,
options: { preserveExistingWindow?: boolean } = {}
options: { cursorMode?: SnapshotCursorMode } = {}
): void {
const fetched = unmask(connection.events);
const newSeen = new SvelteSet<string>();
const merged: RoomEventView[] = [];
const previousOldestCursor = this.oldestCursor;
const previousNewestCursor = this.newestCursor;
const previousHasReachedStart = this.hasReachedStart;
const cursorMode = options.cursorMode ?? 'replace';

for (const e of fetched) {
if (newSeen.has(e.id)) continue;
Expand All @@ -904,11 +912,11 @@ export class MessagesStore {
}

// Preserve subscription events that arrived while the refresh query was in
// flight. Anchored refreshes also preserve already-loaded rows outside the
// fetched window so returning from another tab does not visually collapse a
// long scrolled buffer.
// flight. Soft catch-up refreshes also preserve already-loaded rows outside
// the fetched window so returning from another tab does not visually
// collapse a long scrolled buffer.
for (const e of this.events) {
if (!options.preserveExistingWindow && existingBeforeFetch.has(e.id)) continue;
if (cursorMode === 'replace' && existingBeforeFetch.has(e.id)) continue;
if (newSeen.has(e.id)) continue;
newSeen.add(e.id);
merged.push(e);
Expand All @@ -917,7 +925,11 @@ export class MessagesStore {
this.events = merged;
if (this.scope === 'room') this.sortRoomEvents();
this.seenIds = newSeen;
if (options.preserveExistingWindow) {
if (cursorMode === 'latest') {
this.oldestCursor = previousOldestCursor ?? connection.startCursor ?? undefined;
this.newestCursor = connection.endCursor ?? previousNewestCursor ?? undefined;
this.hasReachedStart = previousHasReachedStart || !(connection.hasOlder ?? false);
} else if (cursorMode === 'preserve') {
this.oldestCursor = previousOldestCursor ?? connection.startCursor ?? undefined;
this.newestCursor = previousNewestCursor ?? connection.endCursor ?? undefined;
this.hasReachedStart = previousHasReachedStart || !(connection.hasOlder ?? false);
Expand All @@ -931,7 +943,8 @@ export class MessagesStore {
preservedExistingCount: merged.length - fetched.length,
eventCount: this.events.length,
hasOlder: connection.hasOlder ?? false,
hasReachedStart: this.hasReachedStart
hasReachedStart: this.hasReachedStart,
cursorMode
});
}

Expand All @@ -941,11 +954,11 @@ export class MessagesStore {
): Promise<RefreshCurrentWindowResult> {
const page = await this.roomTimeline.getRoomEvents({
roomId: this.roomId,
limit: PAGE_SIZE
limit: this.softRefreshLimit()
});

if (this.isStale(thisLoad)) return { hasOlder: false, hasNewer: false, refreshed: false };
this.replaceWithSnapshotAndUpdateCursors(page, existingBeforeFetch);
this.replaceWithSnapshotAndUpdateCursors(page, existingBeforeFetch, { cursorMode: 'latest' });
return { hasOlder: page.hasOlder, hasNewer: page.hasNewer, refreshed: true };
}

Expand All @@ -961,9 +974,7 @@ export class MessagesStore {
});

if (this.isStale(thisLoad)) return { hasOlder: false, hasNewer: false, refreshed: false };
this.replaceWithSnapshotAndUpdateCursors(page, existingBeforeFetch, {
preserveExistingWindow: true
});
this.replaceWithSnapshotAndUpdateCursors(page, existingBeforeFetch, { cursorMode: 'preserve' });
return { hasOlder: page.hasOlder, hasNewer: page.hasNewer, refreshed: true };
}

Expand All @@ -982,11 +993,16 @@ export class MessagesStore {
: await this.roomTimeline.getThreadEvents({
roomId: this.roomId,
threadRootEventId: this.threadRootEventId,
limit: PAGE_SIZE
limit: this.softRefreshLimit()
});
if (this.isStale(thisLoad)) return { hasOlder: false, hasNewer: false, refreshed: false };
this.replaceWithSnapshotAndUpdateCursors(page, existingBeforeFetch, {
preserveExistingWindow: anchorEventId !== null && anchorEventId !== this.threadRootEventId
cursorMode:
anchorEventId === null
? 'latest'
: anchorEventId !== this.threadRootEventId
? 'preserve'
: 'replace'
});
this.sortThreadEvents();
return { hasOlder: page.hasOlder, hasNewer: page.hasNewer, refreshed: true };
Expand Down