사소한 리팩토링

test/server/download.test.ts

@@ -0,0 +1,71 @@
+import { mkdtemp, writeFile } from "fs/promises";
+import { tmpdir } from "os";
+import { join } from "path";
+import { buffer } from "stream/consumers";
+import type { ReadableStream } from "stream/web";
+import { describe, expect, it } from "vitest";
+import { createEncContentStream } from "#lib/server/storage/index.ts";
+
+const createFile = async (content: string) => {
+  const path = join(await mkdtemp(join(tmpdir(), "arkvault-test-")), "file");
+  await writeFile(path, content);
+  return path;
+};
+
+const read = async (stream: unknown) => (await buffer(stream as ReadableStream)).toString();
+
+describe("createEncContentStream", () => {
+  it("serves the whole content when no range is requested", async () => {
+    const path = await createFile("0123456789");
+
+    const { encContentStream, range, isRangeRequest } = await createEncContentStream(path);
+
+    expect(isRangeRequest).toBe(false);
+    expect(range).toEqual({ start: 0, end: 9, total: 10 });
+    expect(await read(encContentStream)).toBe("0123456789");
+  });
+
+  it("serves the requested range", async () => {
+    const path = await createFile("0123456789");
+
+    const { encContentStream, range, isRangeRequest } = await createEncContentStream(
+      path,
+      undefined,
+      { start: 2, end: 5 },
+    );
+
+    expect(isRangeRequest).toBe(true);
+    expect(range).toEqual({ start: 2, end: 5, total: 10 });
+    expect(await read(encContentStream)).toBe("2345");
+  });
+
+  it("serves suffix ranges", async () => {
+    const path = await createFile("0123456789");
+
+    const { encContentStream, range } = await createEncContentStream(path, undefined, {
+      suffixLength: 3,
+    });
+
+    expect(range).toEqual({ start: 7, end: 9, total: 10 });
+    expect(await read(encContentStream)).toBe("789");
+  });
+
+  it("rejects unsatisfiable ranges", async () => {
+    const path = await createFile("0123456789");
+
+    await expect(createEncContentStream(path, undefined, { start: 10 })).rejects.toMatchObject({
+      code: "RANGE_NOT_SATISFIABLE",
+    });
+  });
+
+  it("prepends the legacy IV to the content", async () => {
+    const path = await createFile("6789");
+
+    const { encContentStream } = await createEncContentStream(path, Buffer.from("012345"), {
+      start: 4,
+      end: 7,
+    });
+
+    expect(await read(encContentStream)).toBe("4567");
+  });
+});