tyx_AI_xhs/tests/unit/wp0-06-public-cache.test.ts

import { createHash } from "node:crypto";

import { describe, expect, it } from "vitest";

import { createApp } from "../../apps/api/src/app.js";
import {
  MAX_PUBLIC_CACHE_BYTES,
  buildPublicAssetUrl,
  isPublicCacheDescriptor,
  isPublicServiceWorkerRoute,
  planPublicCacheWrite,
  type PublicAssetLruEntry,
} from "../../apps/web/src/public-asset-cache.js";

const resourceIds = [
  "123e4567-e89b-42d3-a456-426614174001",
  "123e4567-e89b-42d3-a456-426614174002",
  "123e4567-e89b-42d3-a456-426614174003",
  "123e4567-e89b-42d3-a456-426614174004",
] as const;

describe("TDD-WP0-CACHE-001 public allowlist LRU", () => {
  it("freezes the 150 MiB policy and allows exact equality", () => {
    expect(MAX_PUBLIC_CACHE_BYTES).toBe(157_286_400);
    const plan = planPublicCacheWrite([], {
      bytes: MAX_PUBLIC_CACHE_BYTES,
      last_accessed_at: 4,
      release_version: "asset-20260727.2",
      resource_id: resourceIds[0],
    }, MAX_PUBLIC_CACHE_BYTES);
    expect(plan).toEqual({ accepted: true, evict: [], resulting_bytes: MAX_PUBLIC_CACHE_BYTES });
    expect(planPublicCacheWrite([], {
      bytes: MAX_PUBLIC_CACHE_BYTES + 1,
      last_accessed_at: 4,
      release_version: "asset-20260727.2",
      resource_id: resourceIds[0],
    }, MAX_PUBLIC_CACHE_BYTES)).toEqual({ accepted: false, evict: [], resulting_bytes: 0 });
  });

  it("evicts old releases first and then the least recently used entry before writing", () => {
    const entries: PublicAssetLruEntry[] = [
      { bytes: 40, last_accessed_at: 30, release_version: "asset-20260727.1", resource_id: resourceIds[0] },
      { bytes: 40, last_accessed_at: 10, release_version: "asset-20260727.1", resource_id: resourceIds[1] },
      { bytes: 40, last_accessed_at: 1, release_version: "asset-20260727.2", resource_id: resourceIds[2] },
    ];
    const plan = planPublicCacheWrite(entries, {
      bytes: 40,
      last_accessed_at: 40,
      release_version: "asset-20260727.2",
      resource_id: resourceIds[3],
    }, 120);
    expect(plan).toEqual({ accepted: true, evict: [resourceIds[1]], resulting_bytes: 120 });
  });

  it.each([
    { access_class: "internal_preview_asset", cache_kind: "thumbnail" },
    { access_class: "private_user_asset", cache_kind: "thumbnail" },
    { access_class: "public_release_asset", cache_kind: "sticker_original" },
    { access_class: "public_release_asset", cache_kind: "generation" },
    { access_class: "public_release_asset", cache_kind: "export" },
    { access_class: "public_release_asset", cache_kind: "project" },
    { access_class: "public_release_asset", cache_kind: "prompt" },
    { access_class: "public_release_asset", cache_kind: "verification_code" },
    { access_class: "public_release_asset", cache_kind: "session" },
    { access_class: "public_release_asset", cache_kind: "unsaved_edit" },
    { access_class: "public_release_asset", cache_kind: "user_download" },
  ])("rejects non-allowlisted candidate $access_class/$cache_kind", (candidate) => {
    expect(isPublicCacheDescriptor({
      ...candidate,
      release_version: "asset-20260727.2",
      resource_id: resourceIds[0],
    })).toBe(false);
  });

  it.each(["thumbnail", "template_conversion", "font"] as const)("allows public %s only", (cacheKind) => {
    expect(isPublicCacheDescriptor({
      access_class: "public_release_asset",
      cache_kind: cacheKind,
      release_version: "asset-20260727.2",
      resource_id: resourceIds[0],
    })).toBe(true);
  });

  it("constructs and intercepts only same-origin versioned public asset routes", () => {
    const url = buildPublicAssetUrl("asset-20260727.2", resourceIds[0]);
    expect(url).toBe(`/api/v1/assets/public/asset-20260727.2/${resourceIds[0]}`);
    expect(isPublicServiceWorkerRoute(new URL(url, "http://127.0.0.1:43121"), "http://127.0.0.1:43121")).toBe(true);
    for (const path of [
      `/api/v1/assets/preview/asset-20260727.2/${resourceIds[0]}`,
      `/api/v1/private-assets/${resourceIds[0]}`,
      `/api/v1/projects/${resourceIds[0]}`,
      "/api/v1/support/check",
      "file:///C:/private.png",
    ]) {
      expect(isPublicServiceWorkerRoute(new URL(path, "http://127.0.0.1:43121"), "http://127.0.0.1:43121")).toBe(false);
    }
  });

  it("serves existing public binaries as immutable versioned responses with a strong ETag", { timeout: 15_000 }, async () => {
    const bytes = Buffer.from("public-thumbnail");
    const sha256 = createHash("sha256").update(bytes).digest("hex");
    const app = await createApp({
      browserGate: false,
      publicAssets: {
        read: () => ({ assetId: resourceIds[0], bytes, mimeType: "image/png", resourceVersion: "asset-20260727.2", sha256 }),
      },
    });
    const response = await app.inject({
      headers: { host: "127.0.0.1:43121" },
      method: "GET",
      url: `/api/v1/assets/public/asset-20260727.2/${resourceIds[0]}`,
    });
    expect(response.statusCode).toBe(200);
    expect(response.headers["cache-control"]).toBe("public, max-age=31536000, immutable");
    expect(response.headers.etag).toBe(`"sha256-${sha256}"`);
    expect(response.headers["x-content-type-options"]).toBe("nosniff");
    await app.close();
  });
});