perf: coalesce voice library fetches

CHANGELOG.md

@@ -8,6 +8,8 @@ Follows [Keep a Changelog](https://keepachangelog.com/en/1.0.0/) · versioned wi
 ## [Unreleased]
 
 ### Added
+- **Shared Voice-Library Cache.** Library, Benchmark, and Rehearser now share a bounded session cache with in-flight
+  request coalescing and explicit invalidation after voice mutations.
 - **Frontend Namespace Bridge.** A stable `window.TTVC` migration surface now exposes Audiobook, Rehearser, and job
   APIs while preserving legacy globals for compatibility during the larger module split.
 - **Book 2 Attribution Generalization.** The full 1,663-segment Book 2 snapshot is now a regression; structural

TODO.md

@@ -123,7 +123,8 @@ the first block before investing in architecture or polish.
 - [ ] Lazy-load Audiobook, Rehearser, Studio, and image-generation modules only when opened.
 - [x] Paginate large character and voice tables; render approximately 25–50 visible rows, with a constrained-device
   regression covering a 250-character production.
-- [ ] Cache `/api/voices` with explicit invalidation instead of repeated full scans.
+- [x] Cache `/api/voices` with a shared 30-second session cache, one in-flight request, explicit refresh, and
+  invalidation after library metadata/folder mutations; the SQLite voice index remains authoritative.
 - [x] Lazy-load profile images and concept art.
 - [ ] Update only affected table rows instead of rebuilding entire tables.
 - [ ] Add an LRU cache for audio and images and remove old entries automatically. Persisted line-audio is now bounded;

VERSION

@@ -1 +1 @@
-1.24.12
+1.24.13

static/js/benchmark.js

@@ -662,7 +662,7 @@
     if (picker) picker.populate('bench-stt-library-voice', [], { placeholder: 'Loading voices...', empty: 'Loading voices...' });
     else sel.innerHTML = '<option value="">Loading voices...</option>';
     try {
-      const voices = await fetchJson('/api/voices');
+      const voices = await (typeof window.fetchVoiceLibrary === 'function' ? window.fetchVoiceLibrary() : fetchJson('/api/voices'));
       const usable = (voices || [])
         .filter(v => v && v.enabled !== false && v.has_ref && (v.transcript || '').trim())
         .sort((a, b) => String(a.display_name || a.id).localeCompare(String(b.display_name || b.id)));

static/js/rehearser.js

@@ -2314,7 +2314,7 @@ $('reh-matchlib-btn')?.addEventListener('click', async () => {
   let lib = (window._voices || []).filter(v => v.enabled !== false);
   if (!lib.length) {
     // Library metadata isn't loaded yet (opened the Rehearser directly) — fetch it now.
-    try { lib = (await fetch('/api/voices').then(r => r.json())).filter(v => v.enabled !== false); } catch (_) {}
+    try { lib = (await (typeof window.fetchVoiceLibrary === 'function' ? window.fetchVoiceLibrary() : fetch('/api/voices').then(r => r.json()))).filter(v => v.enabled !== false); } catch (_) {}
   }
   if (!lib.length) { toast('Your voice library is empty — clone, design or import some voices first', 'error'); return; }
 

static/js/voice-cache.js

@@ -0,0 +1,41 @@
+// Shared voice-library cache. The backend index is authoritative; this layer
+// prevents multiple frontend panels from starting duplicate scans in one tab.
+(function installVoiceLibraryCache() {
+  const KEY = 'ttsvc_voice_library_cache_v2';
+  const MAX_AGE_MS = 30_000;
+  let inFlight = null;
+
+  function read() {
+    try {
+      const value = JSON.parse(sessionStorage.getItem(KEY) || 'null');
+      if (!value || !Array.isArray(value.voices) || !Number.isFinite(value.savedAt)) return null;
+      return Date.now() - value.savedAt <= MAX_AGE_MS ? value.voices : null;
+    } catch (_) { return null; }
+  }
+  function write(voices) {
+    try { sessionStorage.setItem(KEY, JSON.stringify({ savedAt: Date.now(), voices })); } catch (_) {}
+  }
+  function invalidate() {
+    try { sessionStorage.removeItem(KEY); } catch (_) {}
+  }
+  async function fetchVoices(options = {}) {
+    const refresh = options === true || options.refresh === true;
+    if (!refresh) {
+      const cached = read();
+      if (cached) return cached;
+    }
+    if (inFlight) return inFlight;
+    inFlight = fetch('/api/voices' + (refresh ? '?refresh=1' : ''), { cache: 'no-store' })
+      .then(async response => {
+        if (!response.ok) { const error = await response.json().catch(() => ({})); throw new Error(error.detail || response.statusText); }
+        const voices = await response.json();
+        if (!Array.isArray(voices)) throw new Error('Voice library response was not an array');
+        write(voices);
+        return voices;
+      })
+      .finally(() => { inFlight = null; });
+    return inFlight;
+  }
+  window.fetchVoiceLibrary = fetchVoices;
+  window.invalidateVoiceLibraryCache = invalidate;
+})();

static/js/voice-library.js

@@ -45,7 +45,10 @@ const BENCHMARK_SAMPLE_STORAGE_KEY = 'vcf-benchmark-sample-text';
 const _VL_CACHE_KEY = 'ttsvc_vc';
 
 function _vlCacheRead() {
-  try { return JSON.parse(sessionStorage.getItem(_VL_CACHE_KEY) || 'null'); } catch (_) { return null; }
+  try {
+    const value = JSON.parse(sessionStorage.getItem(_VL_CACHE_KEY) || 'null');
+    return Array.isArray(value) ? value : (Array.isArray(value?.voices) ? value.voices : null);
+  } catch (_) { return null; }
 }
 function _vlCacheWrite(voices) {
   try { sessionStorage.setItem(_VL_CACHE_KEY, JSON.stringify(voices)); } catch (_) {}
@@ -680,9 +683,12 @@ async function loadVoiceLibrary(options = {}) {
     if (list && !silent && renderVisibleList) list.innerHTML = loadingMarkup('Loading voice library', 'Scanning voices, reference text, metadata, ratings, and benchmark results.', 8);
     if (!silent && renderVisibleList) { $('voice-count').textContent = 'Loading voices…'; updateLibraryInsights('loading'); status('Loading voice library…'); }
     try {
-      const r = await fetch('/api/voices' + (forceRefresh ? '?refresh=1' : ''));
-      if (!r.ok) { const e = await r.json().catch(() => ({})); throw new Error(e.detail || r.statusText); }
-      const fresh = await r.json();
+      const fresh = typeof window.fetchVoiceLibrary === 'function'
+        ? await window.fetchVoiceLibrary({ refresh: forceRefresh })
+        : await fetch('/api/voices' + (forceRefresh ? '?refresh=1' : '')).then(async r => {
+          if (!r.ok) throw new Error(r.statusText);
+          return r.json();
+        });
       _vlCacheWrite(fresh);
       _voices = fresh;
       window._voices = _voices;
@@ -715,7 +721,8 @@ $('sync-voice-folders-btn').addEventListener('click', async () => {
     const r = await fetch('/api/voices/sync-folders', { method:'POST' });
     if (!r.ok) { const e = await r.json(); throw new Error(e.detail || r.statusText); }
     const d = await r.json();
-    await loadVoiceLibrary();
+    if (typeof window.invalidateVoiceLibraryCache === 'function') window.invalidateVoiceLibraryCache();
+    await loadVoiceLibrary({ refresh: true });
     const conflicts = d.conflicts && d.conflicts.length ? `, ${d.conflicts.length} conflicts` : '';
     toast(`Synced: ${d.moved.active} active, ${d.moved.hidden} hidden${conflicts}`, d.conflicts && d.conflicts.length ? 'error' : 'success');
     status(`Synced folders. Restart Qwen3-TTS after changing active voices.`);
@@ -3432,6 +3439,7 @@ async function deleteVoiceGroup(group) {
     if (!r.ok) { const e = await r.json().catch(()=>({})); throw new Error(e.detail || r.statusText); }
     const d = await r.json();
     if (window._voiceGroupFilter === group) window._voiceGroupFilter = '';
+    if (typeof window.invalidateVoiceLibraryCache === 'function') window.invalidateVoiceLibraryCache();
     toast(`Moved ${d.count} voice${d.count!==1?'s':''} from "${group}" to Voice Trash`, 'success');
     await loadVoiceLibrary();
   } catch(e) { toast('Delete failed: ' + e.message, 'error'); }
@@ -3444,6 +3452,7 @@ async function saveMeta(voiceId, patch) {
     const e = await r.json().catch(() => ({}));
     throw new Error(e.detail || r.statusText);
   }
+  if (typeof window.invalidateVoiceLibraryCache === 'function') window.invalidateVoiceLibraryCache();
   return r.json();
 }
 

static/module-manifest.json

@@ -1,5 +1,5 @@
 [
-  "voice-picker", "benchmark-voice-picker", "voice-inspector", "seed-finder", "voice-sources", "fishaudio-browser", "jobs",
+  "voice-picker", "benchmark-voice-picker", "voice-inspector", "seed-finder", "voice-sources", "fishaudio-browser", "voice-cache", "jobs",
   "integrations", "routing", "voice-clone", "voice-library", "tts-preview", "generation", "benchmark", "stt",
   "rehearser-parse", "rehearser", "reader", "audiobook", "audiobook/network", "character-sheets",
   "characters-library", "sillytavern", "library", "character-columns", "library-characters", "studio", "namespace"

tests/constrained.spec.js

@@ -61,3 +61,27 @@ test('desktop navigation remains usable under Chrome CPU throttling', async ({ p
     await cdp.detach().catch(() => {});
   }
 });
+
+test('voice library cache reuses fresh data and honors explicit refresh', async ({ page }) => {
+  await page.goto('/', { waitUntil: 'domcontentloaded' });
+  await page.waitForFunction(() => typeof window.fetchVoiceLibrary === 'function', null, { timeout: 15_000 });
+  const result = await page.evaluate(async () => {
+    sessionStorage.removeItem('ttsvc_voice_library_cache_v2');
+    let calls = 0;
+    const originalFetch = window.fetch;
+    window.fetch = async (url, options) => {
+      if (String(url).startsWith('/api/voices')) {
+        calls += 1;
+        return new Response(JSON.stringify([{ id: 'cached-voice' }]), { status: 200, headers: { 'Content-Type': 'application/json' } });
+      }
+      return originalFetch(url, options);
+    };
+    try {
+      await window.fetchVoiceLibrary({ refresh: true });
+      await window.fetchVoiceLibrary();
+      await window.fetchVoiceLibrary({ refresh: true });
+      return calls;
+    } finally { window.fetch = originalFetch; }
+  });
+  expect(result).toBe(2);
+});