perf(studio-server): coordinate cancelable thumbnail generation (#2720)

* perf(studio): schedule adaptive timeline thumbnails * perf(studio): bound thumbnail decoding resources * perf(studio): virtualize timeline thumbnail media * perf(studio): prioritize timeline thumbnail work * perf(studio-server): coordinate cancelable thumbnail generation --------- Co-authored-by: Codex <codex@local>
2026-09-11 06:30:03 +00:00 · 2026-08-05 20:41:35 -07:00
parent 27d113e56c
commit 96861cbafc
59 changed files with 3537 additions and 879 deletions
@@ -0,0 +1,81 @@
+// @vitest-environment happy-dom
+
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { getMediaProbeDiagnostics, probeMediaUrl, resetMediaProbeRegistry } from "./mediaProbe";
+
+const dispose = vi.fn();
+const getDurationFromMetadata = vi.fn(async () => 5);
+
+vi.mock("mediabunny", () => ({
+  ALL_FORMATS: {},
+  UrlSource: class {
+    constructor(readonly url: string) {}
+  },
+  Input: class {
+    getDurationFromMetadata = getDurationFromMetadata;
+    getPrimaryVideoTrack = vi.fn(async () => ({ displayWidth: 640, displayHeight: 360 }));
+    getAudioTracks = vi.fn(async () => []);
+    dispose = dispose;
+  },
+}));
+
+beforeEach(() => {
+  resetMediaProbeRegistry();
+  vi.clearAllMocks();
+  getDurationFromMetadata.mockResolvedValue(5);
+});
+
+afterEach(() => {
+  vi.useRealTimers();
+});
+
+describe("media probe registry", () => {
+  it("deduplicates and caches successful probes", async () => {
+    const [first, second] = await Promise.all([
+      probeMediaUrl("/video.mp4"),
+      probeMediaUrl("/video.mp4"),
+    ]);
+    expect(first).toEqual(second);
+    expect(getDurationFromMetadata).toHaveBeenCalledTimes(1);
+    expect(dispose).toHaveBeenCalledTimes(1);
+    expect(getMediaProbeDiagnostics()).toEqual({ cached: 1, failed: 0, inflight: 0 });
+  });
+
+  it("bounds retained successes to the configured registry count", async () => {
+    for (let index = 0; index < 513; index++) {
+      await probeMediaUrl(`/video-${index}.mp4`);
+    }
+    expect(getMediaProbeDiagnostics().cached).toBe(512);
+  });
+
+  it("limits concurrent metadata probes and drains the queue", async () => {
+    const resolvers: Array<(duration: number) => void> = [];
+    getDurationFromMetadata.mockImplementation(
+      () => new Promise<number>((resolve) => resolvers.push(resolve)),
+    );
+
+    const probes = Array.from({ length: 5 }, (_, index) => probeMediaUrl(`/queued-${index}.mp4`));
+    await Promise.resolve();
+    await Promise.resolve();
+    expect(getDurationFromMetadata).toHaveBeenCalledTimes(4);
+
+    resolvers[0]?.(5);
+    await vi.waitFor(() => expect(getDurationFromMetadata).toHaveBeenCalledTimes(5));
+
+    for (const resolve of resolvers.slice(1)) resolve(5);
+    await expect(Promise.all(probes)).resolves.toHaveLength(5);
+    expect(getMediaProbeDiagnostics()).toEqual({ cached: 5, failed: 0, inflight: 0 });
+  });
+
+  it("retries failures only after the failure TTL", async () => {
+    vi.useFakeTimers();
+    getDurationFromMetadata.mockRejectedValue(new Error("bad source"));
+    await expect(probeMediaUrl("/bad.mp4")).resolves.toBeNull();
+    await expect(probeMediaUrl("/bad.mp4")).resolves.toBeNull();
+    expect(getDurationFromMetadata).toHaveBeenCalledTimes(1);
+
+    vi.advanceTimersByTime(30_001);
+    await expect(probeMediaUrl("/bad.mp4")).resolves.toBeNull();
+    expect(getDurationFromMetadata).toHaveBeenCalledTimes(2);
+  });
+});