perf(frontend): load favorite/share badges once per session, not per navigation

The files browser re-fetched the first 200 favorites AND the first 200 outgoing
shares on every folder navigation (two round-trips each time) just to render the
star / shared badges — work that grew with how much the user browsed, for data
that barely changes.

Move both id sets into a session-scoped `badges` store: `ensureLoaded()` fetches
once (concurrent callers share one in-flight request) and every later navigation
reads from cache, so browsing costs zero extra requests. Mutations keep the cache
in sync optimistically:
- favorite toggle / batch-favorite → `setFavorite` (revert on failure),
- share creation → `markShared`, wired through a new optional `onshared` callback
  on ShareDialog (fired when a grant or public link is created). This also makes
  the shared badge appear immediately instead of only after re-navigating.

Net effect per session: badge fetches drop from O(navigations) × 2 to 2 total.
The 200-item ceiling is unchanged from before; the fully-correct fix is per-item
flags on the listing endpoint (a backend change, noted in the store).

Verified: new badges store unit tests (load-once, concurrent de-dupe, optimistic
favorite/share, reset) and a headless render of the real files route in list and
grid (virtualization intact, no runtime errors).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01M8Vb9QHmLZnEMzHz7MrFy6

frontend/src/lib/components/ShareDialog.svelte

@@ -43,9 +43,11 @@
 	interface Props {
 		open: boolean;
 		item: Target | null;
+		/** Fired with the item id when an outgoing share (grant or link) is created. */
+		onshared?: (id: string) => void;
 	}
 
-	let { open = $bindable(false), item }: Props = $props();
+	let { open = $bindable(false), item, onshared }: Props = $props();
 
 	let tab = $state<'people' | 'link'>('people');
 	let directoryAvailable = $state(true);
@@ -159,6 +161,7 @@
 			query = '';
 			results = [];
 			summarizeNotifications(res.notification.outcomes);
+			onshared?.(item.id);
 			await loadGrants();
 		} catch (e) {
 			errorToast(e);
@@ -280,6 +283,7 @@
 			newLinkName = '';
 			password = '';
 			expiresAt = null;
+			onshared?.(item.id);
 			await loadShares();
 			ui.notify(t('share.created', 'Public link created'), 'success');
 		} catch (e) {

frontend/src/lib/stores/badges.svelte.ts

@@ -0,0 +1,73 @@
+/**
+ * Session-scoped favorite / outgoing-share badge sets.
+ *
+ * The files browser shows a star (favorite) and a link (shared) badge per row.
+ * Previously every folder navigation re-fetched the first 200 favorites AND the
+ * first 200 shares — two round-trips per navigation, for data that barely
+ * changes. This caches both id sets once per session (`ensureLoaded`, deduped)
+ * and keeps them in sync via optimistic mutations from the views that toggle
+ * them, so navigating folders costs zero extra requests.
+ *
+ * (The 200-item ceiling is inherited from the previous implementation; the truly
+ * complete fix is to have the listing endpoint return per-item flags, a backend
+ * change tracked separately.)
+ */
+import { fetchFavoritesPage } from '$lib/api/endpoints/favorites';
+import { fetchMyShares } from '$lib/api/endpoints/grants';
+
+class BadgesStore {
+	#favorites = $state<Set<string>>(new Set());
+	#shared = $state<Set<string>>(new Set());
+	#loaded = false;
+	#inflight: Promise<void> | null = null;
+
+	isFavorite(id: string): boolean {
+		return this.#favorites.has(id);
+	}
+
+	isShared(id: string): boolean {
+		return this.#shared.has(id);
+	}
+
+	/** Load both id sets once per session. Concurrent callers share one fetch. */
+	ensureLoaded(): Promise<void> {
+		if (this.#loaded) return Promise.resolve();
+		if (this.#inflight) return this.#inflight;
+		this.#inflight = (async () => {
+			const [favs, shares] = await Promise.all([
+				fetchFavoritesPage({ limit: 200 }).catch(() => null),
+				fetchMyShares({ limit: 200 }).catch(() => null)
+			]);
+			if (favs) this.#favorites = new Set(favs.items.map((f) => f.resource.id));
+			if (shares) this.#shared = new Set(shares.items.map((s) => s.resource.id));
+			this.#loaded = true;
+			this.#inflight = null;
+		})();
+		return this.#inflight;
+	}
+
+	/** Optimistically reflect a favorite toggle (no refetch). */
+	setFavorite(id: string, on: boolean): void {
+		if (on === this.#favorites.has(id)) return;
+		const next = new Set(this.#favorites);
+		if (on) next.add(id);
+		else next.delete(id);
+		this.#favorites = next;
+	}
+
+	/** Mark an item as having an outgoing share (after one is created). */
+	markShared(id: string): void {
+		if (this.#shared.has(id)) return;
+		this.#shared = new Set(this.#shared).add(id);
+	}
+
+	/** Drop the cache (e.g. on logout) so the next session reloads fresh. */
+	reset(): void {
+		this.#favorites = new Set();
+		this.#shared = new Set();
+		this.#loaded = false;
+		this.#inflight = null;
+	}
+}
+
+export const badges = new BadgesStore();

frontend/src/lib/stores/badges.test.ts

@@ -0,0 +1,75 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+vi.mock('$lib/api/endpoints/favorites', () => ({ fetchFavoritesPage: vi.fn() }));
+vi.mock('$lib/api/endpoints/grants', () => ({ fetchMyShares: vi.fn() }));
+
+import { fetchFavoritesPage } from '$lib/api/endpoints/favorites';
+import { fetchMyShares } from '$lib/api/endpoints/grants';
+import { badges } from './badges.svelte';
+
+const favPage = (...ids: string[]) =>
+	({ items: ids.map((id) => ({ resource: { id } })) }) as unknown as Awaited<
+		ReturnType<typeof fetchFavoritesPage>
+	>;
+const sharePage = (...ids: string[]) =>
+	({ items: ids.map((id) => ({ resource: { id } })) }) as unknown as Awaited<
+		ReturnType<typeof fetchMyShares>
+	>;
+
+beforeEach(() => {
+	vi.clearAllMocks();
+	vi.mocked(fetchFavoritesPage).mockResolvedValue(favPage('f1', 'f2'));
+	vi.mocked(fetchMyShares).mockResolvedValue(sharePage('s1'));
+	badges.reset();
+});
+
+describe('badges store', () => {
+	it('loads once and serves every later navigation from cache', async () => {
+		// Five "folder navigations" each call ensureLoaded.
+		for (let i = 0; i < 5; i++) await badges.ensureLoaded();
+
+		expect(fetchFavoritesPage).toHaveBeenCalledTimes(1);
+		expect(fetchMyShares).toHaveBeenCalledTimes(1);
+		expect(badges.isFavorite('f1')).toBe(true);
+		expect(badges.isFavorite('f2')).toBe(true);
+		expect(badges.isShared('s1')).toBe(true);
+		expect(badges.isFavorite('nope')).toBe(false);
+	});
+
+	it('collapses concurrent loads into a single fetch', async () => {
+		await Promise.all([
+			badges.ensureLoaded(),
+			badges.ensureLoaded(),
+			badges.ensureLoaded(),
+			badges.ensureLoaded()
+		]);
+		expect(fetchFavoritesPage).toHaveBeenCalledTimes(1);
+		expect(fetchMyShares).toHaveBeenCalledTimes(1);
+	});
+
+	it('reflects favorite toggles optimistically without refetching', async () => {
+		await badges.ensureLoaded();
+		badges.setFavorite('x', true);
+		expect(badges.isFavorite('x')).toBe(true);
+		badges.setFavorite('x', false);
+		expect(badges.isFavorite('x')).toBe(false);
+		// No extra network for optimistic updates.
+		expect(fetchFavoritesPage).toHaveBeenCalledTimes(1);
+	});
+
+	it('marks an item shared after a share is created', async () => {
+		await badges.ensureLoaded();
+		expect(badges.isShared('new')).toBe(false);
+		badges.markShared('new');
+		expect(badges.isShared('new')).toBe(true);
+	});
+
+	it('reset() clears the cache and allows a fresh reload', async () => {
+		await badges.ensureLoaded();
+		expect(fetchFavoritesPage).toHaveBeenCalledTimes(1);
+		badges.reset();
+		expect(badges.isFavorite('f1')).toBe(false);
+		await badges.ensureLoaded();
+		expect(fetchFavoritesPage).toHaveBeenCalledTimes(2);
+	});
+});

frontend/src/routes/files/[...path]/+page.svelte

@@ -25,8 +25,7 @@
 	} from '$lib/api/endpoints/files';
 	import { folderZipUrl } from '$lib/api/endpoints/folders';
 	import { tryDeltaUpload } from '$lib/api/endpoints/deltaUpload';
-	import { addFavorite, fetchFavoritesPage, removeFavorite } from '$lib/api/endpoints/favorites';
+	import { addFavorite, removeFavorite } from '$lib/api/endpoints/favorites';
-	import { fetchMyShares } from '$lib/api/endpoints/grants';
 	import { canEditWithWopi, getEditorUrlWithFallback } from '$lib/api/endpoints/wopi';
 	import { addTracks, createPlaylist, listPlaylists } from '$lib/api/endpoints/music';
 	import { apiFetch } from '$lib/api/client';
@@ -40,6 +39,7 @@
 	import WopiEditor from '$lib/components/WopiEditor.svelte';
 	import { t } from '$lib/i18n/index.svelte';
 	import { confirmDialog, promptDialog } from '$lib/stores/dialogs.svelte';
+	import { badges } from '$lib/stores/badges.svelte';
 	import { files as filesStore } from '$lib/stores/files.svelte';
 	import { session } from '$lib/stores/session.svelte';
 	import { ui } from '$lib/stores/ui.svelte';
@@ -80,10 +80,6 @@
 	let actionTarget = $state<ActionTarget | null>(null);
 	let moveItems = $state<ActionTarget[] | null>(null);
 
-	// Favorite + shared badges for items in the current folder.
-	let favoriteIds = $state<Set<string>>(new Set());
-	let sharedIds = $state<Set<string>>(new Set());
-
 	function openMove(kind: ItemType, id: string, name: string) {
 		actionTarget = { id, name, kind };
 		moveItems = null;
@@ -101,33 +97,16 @@
 		shareOpen = true;
 	}
 
-	/** Load favorite + outgoing-share id sets so items can show badges. */
-	async function loadBadges() {
-		try {
-			const [favs, shares] = await Promise.all([
-				fetchFavoritesPage({ limit: 200 }).catch(() => null),
-				fetchMyShares({ limit: 200 }).catch(() => null)
-			]);
-			favoriteIds = new Set((favs?.items ?? []).map((f) => f.resource.id));
-			sharedIds = new Set((shares?.items ?? []).map((s) => s.resource.id));
-		} catch {
-			/* badges are best-effort */
-		}
-	}
-
 	async function toggleFavorite(kind: ItemType, id: string) {
-		const isFav = favoriteIds.has(id);
+		const isFav = badges.isFavorite(id);
-		// Optimistic toggle, reconcile on failure.
+		// Optimistic toggle, reverted on failure.
-		const next = new Set(favoriteIds);
+		badges.setFavorite(id, !isFav);
-		if (isFav) next.delete(id);
-		else next.add(id);
-		favoriteIds = next;
 		try {
 			if (isFav) await removeFavorite(kind, id);
 			else await addFavorite(kind, id);
 		} catch (e) {
 			errorToast(e);
-			await loadBadges();
+			badges.setFavorite(id, isFav);
 		}
 	}
 
@@ -168,7 +147,7 @@
 			const [data, trail] = await Promise.all([listFolder(folderId), buildCrumbs(pathSegments)]);
 			listing = data;
 			crumbs = trail;
-			void loadBadges();
+			void badges.ensureLoaded();
 			maybeOpenDeepLink();
 		} catch (e) {
 			// 403 → friendly message rather than the raw "Forbidden" error string.
@@ -444,7 +423,7 @@
 
 	/** Batch add the selection to favorites — single /api/favorites/batch call. */
 	async function batchFavorites() {
-		const items = selectionTargets().filter((it) => !favoriteIds.has(it.id));
+		const items = selectionTargets().filter((it) => !badges.isFavorite(it.id));
 		if (items.length === 0) {
 			ui.notify(t('files.already_favorites', 'All selected items are already favorites'), 'info');
 			clearSelection();
@@ -460,10 +439,9 @@
 				})
 			});
 			if (!res.ok) throw new Error(`Server returned ${res.status}`);
-			favoriteIds = new Set([...favoriteIds, ...items.map((it) => it.id)]);
+			for (const it of items) badges.setFavorite(it.id, true);
 			ui.notify(t('files.added_favorites', 'Added to favorites'), 'success');
 			clearSelection();
-			void loadBadges();
 		} catch (e) {
 			errorToast(e);
 		}
@@ -1218,13 +1196,13 @@
 		<div class="name-cell">
 			<div class="file-icon"><Icon name="folder" /></div>
 			<span title={folder.name}>{folder.name}</span>
-			{#if favoriteIds.has(folder.id)}<div
+			{#if badges.isFavorite(folder.id)}<div
 					class="item-badge item-badge--fav"
 					title={t('files.favorited', 'Favorite')}
 				>
 					<Icon name="star" />
 				</div>{/if}
-			{#if sharedIds.has(folder.id)}<div
+			{#if badges.isShared(folder.id)}<div
 					class="file-badge file-badge-shared"
 					title={t('files.shared', 'Shared')}
 				>
@@ -1241,15 +1219,15 @@
 		<div class="action-cell">
 			<button
 				class="favorite-star"
-				class:active={favoriteIds.has(folder.id)}
+				class:active={badges.isFavorite(folder.id)}
-				title={favoriteIds.has(folder.id)
+				title={badges.isFavorite(folder.id)
 					? t('files.unfavorite', 'Remove favorite')
 					: t('files.favorite', 'Add favorite')}
-				aria-pressed={favoriteIds.has(folder.id)}
+				aria-pressed={badges.isFavorite(folder.id)}
 				onclick={(e) => {
 					e.stopPropagation();
 					void toggleFavorite('folder', folder.id);
-				}}><Icon name={favoriteIds.has(folder.id) ? 'star' : 'star-outline'} /></button
+				}}><Icon name={badges.isFavorite(folder.id) ? 'star' : 'star-outline'} /></button
 			>
 			<button
 				class="btn-action"
@@ -1336,13 +1314,13 @@
 				{/if}
 			</div>
 			<span title={file.name}>{file.name}</span>
-			{#if favoriteIds.has(file.id)}<div
+			{#if badges.isFavorite(file.id)}<div
 					class="item-badge item-badge--fav"
 					title={t('files.favorited', 'Favorite')}
 				>
 					<Icon name="star" />
 				</div>{/if}
-			{#if sharedIds.has(file.id)}<div
+			{#if badges.isShared(file.id)}<div
 					class="file-badge file-badge-shared"
 					title={t('files.shared', 'Shared')}
 				>
@@ -1360,15 +1338,15 @@
 		<div class="action-cell">
 			<button
 				class="favorite-star"
-				class:active={favoriteIds.has(file.id)}
+				class:active={badges.isFavorite(file.id)}
-				title={favoriteIds.has(file.id)
+				title={badges.isFavorite(file.id)
 					? t('files.unfavorite', 'Remove favorite')
 					: t('files.favorite', 'Add favorite')}
-				aria-pressed={favoriteIds.has(file.id)}
+				aria-pressed={badges.isFavorite(file.id)}
 				onclick={(e) => {
 					e.stopPropagation();
 					void toggleFavorite('file', file.id);
-				}}><Icon name={favoriteIds.has(file.id) ? 'star' : 'star-outline'} /></button
+				}}><Icon name={badges.isFavorite(file.id) ? 'star' : 'star-outline'} /></button
 			>
 			<button
 				class="btn-action"
@@ -1431,7 +1409,7 @@
 		void load();
 	}}
 />
-<ShareDialog bind:open={shareOpen} item={actionTarget} />
+<ShareDialog bind:open={shareOpen} item={actionTarget} onshared={(id) => badges.markShared(id)} />
 <FileViewer bind:open={viewerOpen} file={viewerFile} />
 <WopiEditor
 	bind:open={wopiOpen}
@@ -1562,7 +1540,7 @@
 			}}
 		>
 			<Icon name="star" />
-			{favoriteIds.has(ctxTarget.id)
+			{badges.isFavorite(ctxTarget.id)
 				? t('files.unfavorite', 'Remove favorite')
 				: t('files.favorite', 'Add favorite')}
 		</button>