Verify and restore the complete Minecraft asset cache

scripts/assets.mjs

@@ -1,4 +1,4 @@
-import { mkdir, readFile, writeFile } from "node:fs/promises";
+import { mkdir, readFile, stat, writeFile } from "node:fs/promises";
 import { createHash } from "node:crypto";
 import { unzipSync } from "fflate";
 export const assetsRoot = ".cache/minecraft/1.21.11";
@@ -24,13 +24,38 @@ async function assetsReady(minecraftVersion) {
   try {
     const marker = JSON.parse(await readFile(completionMarker, "utf8"));
     if (
-      marker.format !== "minegeo-assets/v2" ||
+      marker.format !== "minegeo-assets/v3" ||
       marker.minecraftVersion !== minecraftVersion ||
-      !marker.files
+      !marker.files ||
+      !Array.isArray(marker.entries) ||
+      marker.entries.length !== marker.files
     )
       return false;
-    // A blockstate alone is insufficient: interrupted setup can leave models
-    // and textures absent. The marker is only written after all extraction.
+    // Verify the complete extracted inventory, not just common blocks. A
+    // partial cache otherwise silently drops newer or less common textures.
+    let next = 0;
+    await Promise.all(
+      Array.from({ length: 16 }, async () => {
+        while (next < marker.entries.length) {
+          const entry = marker.entries[next++];
+          if (
+            !Array.isArray(entry) ||
+            entry.length !== 2 ||
+            typeof entry[0] !== "string" ||
+            !/^assets\/minecraft\/(models|blockstates|textures)\/[a-z0-9_./-]+\.(json|png|mcmeta)$/.test(
+              entry[0],
+            ) ||
+            entry[0].includes("..") ||
+            !Number.isSafeInteger(entry[1]) ||
+            entry[1] < 1
+          )
+            throw new Error("Invalid asset inventory");
+          const info = await stat(`${assetsRoot}/${entry[0]}`);
+          if (!info.isFile() || info.size !== entry[1])
+            throw new Error("Missing asset");
+        }
+      }),
+    );
     for (const asset of requiredAssets) {
       const bytes = await readFile(`${assetsRoot}/assets/minecraft/${asset}`);
       if (asset.endsWith(".json")) JSON.parse(bytes.toString());
@@ -96,23 +121,41 @@ export async function prepareAssets(minecraftVersion = "1.21.11") {
   }
   const entries = unzipSync(jar, {
     filter: (f) =>
-      /^assets\/minecraft\/(models|blockstates|textures\/block)\//.test(
-        f.name,
-      ) && /\.(json|png|mcmeta)$/.test(f.name),
+      /^assets\/minecraft\/(models|blockstates|textures)\//.test(f.name) &&
+      /\.(json|png|mcmeta)$/.test(f.name),
   });
-  for (const [name, bytes] of Object.entries(entries)) {
-    const path = `${assetsRoot}/${name}`;
-    await mkdir(path.slice(0, path.lastIndexOf("/")), { recursive: true });
-    await writeFile(path, bytes);
-  }
+  const files = Object.entries(entries);
+  const directories = new Set(
+    files.map(
+      ([name]) => `${assetsRoot}/${name.slice(0, name.lastIndexOf("/"))}`,
+    ),
+  );
+  await Promise.all(
+    [...directories].map((path) => mkdir(path, { recursive: true })),
+  );
+  let nextFile = 0;
+  const writes = await Promise.allSettled(
+    Array.from({ length: Math.min(16, files.length) }, async () => {
+      while (nextFile < files.length) {
+        const [name, bytes] = files[nextFile++];
+        await writeFile(`${assetsRoot}/${name}`, bytes);
+      }
+    }),
+  );
+  const failedWrite = writes.find((result) => result.status === "rejected");
+  if (failedWrite?.status === "rejected") throw failedWrite.reason;
   // Completion is recorded last, so a killed extraction is repaired next time.
   await writeFile(
     completionMarker,
     JSON.stringify({
-      format: "minegeo-assets/v2",
+      format: "minegeo-assets/v3",
       minecraftVersion,
       clientSha1: version.downloads.client.sha1,
       files: Object.keys(entries).length,
+      entries: Object.entries(entries).map(([name, bytes]) => [
+        name,
+        bytes.length,
+      ]),
     }),
   );
   if (!(await assetsReady(minecraftVersion)))

tests/renderer-assets.test.ts

@@ -23,6 +23,8 @@ const files = {
   "textures/block/dirt.png": png,
   "textures/block/stone.png": png,
   "textures/block/water_still.png": png,
+  "textures/block/newer_fixture.png": png,
+  "textures/entity/newer_fixture.png": png,
   "textures/block/water_still.png.mcmeta": Buffer.from(
     '{"animation":{"frametime":2}}',
   ),
@@ -145,6 +147,17 @@ test("a complete marker with a missing texture is repaired from the verified cac
   assert.equal(requests.filter((url) => url.endsWith("client.jar")).length, 0);
 });
 
+test("missing non-core 26.2 textures are restored from the verified client", async (t) => {
+  const requests = await isolatedCache(t, false, "26.2");
+  const directory = await prepareAssets("26.2");
+  const path = `${directory}/assets/minecraft/textures/block/newer_fixture.png`;
+  await rm(path);
+  requests.length = 0;
+  await prepareAssets("26.2");
+  assert.deepEqual(await readFile(path), png);
+  assert.equal(requests.filter((url) => url.endsWith("client.jar")).length, 0);
+});
+
 test("a corrupted cached client is downloaded again", async (t) => {
   const requests = await isolatedCache(t);
   await mkdir(".cache/minecraft", { recursive: true });