feat: v2

tests/server/cas.test.ts

@@ -0,0 +1,71 @@
+import { afterEach, describe, expect, test } from "bun:test";
+import { createHash } from "node:crypto";
+import { mkdir, mkdtemp, rm, symlink, writeFile } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { FilesystemCas } from "../../server/cas";
+import type { Sha256Digest } from "../../shared/build-protocol";
+
+const roots: string[] = [];
+afterEach(async () => {
+  await Promise.all(
+    roots.splice(0).map((root) => rm(root, { recursive: true, force: true })),
+  );
+});
+
+function digest(value: string): Sha256Digest {
+  return `sha256:${createHash("sha256").update(value).digest("hex")}`;
+}
+
+describe("filesystem CAS", () => {
+  test("stores, deduplicates, and verifies blobs", async () => {
+    const root = await mkdtemp(join(tmpdir(), "kuber-cas-"));
+    roots.push(root);
+    const cas = new FilesystemCas(root);
+    const expected = digest("hello");
+    expect(await cas.put(Buffer.from("hello"), expected)).toBe(expected);
+    expect(await cas.has(expected)).toBe(true);
+    expect(Buffer.from(await cas.get(expected)).toString()).toBe("hello");
+    expect(
+      await Promise.all(
+        Array.from({ length: 8 }, () => cas.put(Buffer.from("hello"))),
+      ),
+    ).toEqual(Array(8).fill(expected));
+    await expect(cas.put(Buffer.from("other"), expected)).rejects.toThrow(
+      "digest mismatch",
+    );
+  });
+
+  test("detects corruption on reads and existing writes", async () => {
+    const root = await mkdtemp(join(tmpdir(), "kuber-cas-"));
+    roots.push(root);
+    const cas = new FilesystemCas(root);
+    const expected = await cas.put(Buffer.from("hello"));
+    const hex = expected.slice(7);
+    await writeFile(
+      join(root, "sha256", hex.slice(0, 2), hex.slice(2)),
+      "tampered",
+    );
+    await expect(cas.get(expected)).rejects.toThrow("Corrupt CAS blob");
+    await expect(cas.put(Buffer.from("hello"))).rejects.toThrow(
+      "Corrupt CAS blob",
+    );
+  });
+
+  test("does not follow a blob-path symlink", async () => {
+    const root = await mkdtemp(join(tmpdir(), "kuber-cas-"));
+    const outside = await mkdtemp(join(tmpdir(), "kuber-cas-outside-"));
+    roots.push(root, outside);
+    const cas = new FilesystemCas(root);
+    const expected = digest("hello");
+    const hex = expected.slice(7);
+    await writeFile(join(outside, "blob"), "hello");
+    await mkdir(join(root, "sha256", hex.slice(0, 2)), { recursive: true });
+    await symlink(
+      join(outside, "blob"),
+      join(root, "sha256", hex.slice(0, 2), hex.slice(2)),
+    );
+    expect(await cas.has(expected)).toBe(false);
+    await expect(cas.get(expected)).rejects.toThrow();
+  });
+});