feat: stream S3 object bodies from Telegram parts

2026-07-07 04:25:05 +07:00
parent 5253fb384d
commit 378a084fd3
2 changed files with 195 additions and 0 deletions
@@ -0,0 +1,85 @@
+import { afterEach, describe, expect, it } from 'bun:test';
+import { createGetObjectResponse } from '../src/utils/s3/object-stream';
+
+const originalFetch = globalThis.fetch;
+
+const streamText = (text: string) => new Response(text).body!;
+
+const installFetch = () => {
+  globalThis.fetch = (async (_url: string | URL | Request, init?: RequestInit) => {
+    const range = new Headers(init?.headers).get('range');
+    const url = String(_url);
+    const text = url.includes('part-1') ? 'hello ' : 'world';
+    if (range === 'bytes=1-3') {
+      return new Response(text.slice(1, 4), {
+        status: 206,
+        headers: { 'content-range': `bytes 1-3/${text.length}`, 'content-length': '3' },
+      });
+    }
+    return new Response(streamText(text), {
+      status: 200,
+      headers: { 'content-length': String(text.length) },
+    });
+  }) as typeof fetch;
+};
+
+afterEach(() => {
+  globalThis.fetch = originalFetch;
+});
+
+describe('S3 object stream response builder', () => {
+  it('concatenates multiple Telegram part streams', async () => {
+    installFetch();
+    const res = await createGetObjectResponse({
+      reqId: 'req-1',
+      contentType: 'text/plain',
+      etag: 'etag123',
+      lastModified: new Date('2026-07-07T00:00:00Z'),
+      totalSize: 11,
+      parts: [
+        {
+          telegramFileId: 'part-1',
+          telegramUrl: 'https://telegram.test/part-1',
+          sizeBytes: 6,
+          partNumber: 1,
+        },
+        {
+          telegramFileId: 'part-2',
+          telegramUrl: 'https://telegram.test/part-2',
+          sizeBytes: 5,
+          partNumber: 2,
+        },
+      ],
+      range: { type: 'none' },
+    });
+
+    expect(res.status).toBe(200);
+    expect(res.headers.get('content-length')).toBe('11');
+    expect(await res.text()).toBe('hello world');
+  });
+
+  it('returns 206 with content-range for a single-part byte range', async () => {
+    installFetch();
+    const res = await createGetObjectResponse({
+      reqId: 'req-2',
+      contentType: 'text/plain',
+      etag: 'etag123',
+      lastModified: new Date('2026-07-07T00:00:00Z'),
+      totalSize: 6,
+      parts: [
+        {
+          telegramFileId: 'part-1',
+          telegramUrl: 'https://telegram.test/part-1',
+          sizeBytes: 6,
+          partNumber: 1,
+        },
+      ],
+      range: { type: 'valid', start: 1, end: 3 },
+    });
+
+    expect(res.status).toBe(206);
+    expect(res.headers.get('content-range')).toBe('bytes 1-3/6');
+    expect(res.headers.get('content-length')).toBe('3');
+    expect(await res.text()).toBe('ell');
+  });
+});