feat(queue): implement local adapter with JSON persistence

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/queue/src/adapters/local.test.ts

@@ -0,0 +1,81 @@
+import { mkdtempSync, rmSync } from 'node:fs';
+import { join } from 'node:path';
+import { tmpdir } from 'node:os';
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+
+import type { TaskPayload } from '../types.js';
+import { createLocalAdapter } from './local.js';
+
+function makePayload(id: string): TaskPayload {
+  return { id, type: 'test', data: { value: id }, createdAt: new Date().toISOString() };
+}
+
+describe('LocalAdapter', () => {
+  let dataDir: string;
+
+  beforeEach(() => {
+    dataDir = mkdtempSync(join(tmpdir(), 'mosaic-queue-test-'));
+  });
+
+  afterEach(() => {
+    rmSync(dataDir, { recursive: true, force: true });
+  });
+
+  it('enqueue + dequeue in FIFO order', async () => {
+    const adapter = createLocalAdapter({ type: 'local', dataDir });
+    const a = makePayload('a');
+    const b = makePayload('b');
+    const c = makePayload('c');
+
+    await adapter.enqueue('tasks', a);
+    await adapter.enqueue('tasks', b);
+    await adapter.enqueue('tasks', c);
+
+    expect(await adapter.dequeue('tasks')).toEqual(a);
+    expect(await adapter.dequeue('tasks')).toEqual(b);
+    expect(await adapter.dequeue('tasks')).toEqual(c);
+    expect(await adapter.dequeue('tasks')).toBeNull();
+  });
+
+  it('length accuracy', async () => {
+    const adapter = createLocalAdapter({ type: 'local', dataDir });
+
+    expect(await adapter.length('q')).toBe(0);
+    await adapter.enqueue('q', makePayload('1'));
+    await adapter.enqueue('q', makePayload('2'));
+    expect(await adapter.length('q')).toBe(2);
+    await adapter.dequeue('q');
+    expect(await adapter.length('q')).toBe(1);
+  });
+
+  it('publish + subscribe delivery', async () => {
+    const adapter = createLocalAdapter({ type: 'local', dataDir });
+    const received: string[] = [];
+
+    const unsub = adapter.subscribe('chan', (msg) => received.push(msg));
+    await adapter.publish('chan', 'hello');
+    await adapter.publish('chan', 'world');
+
+    expect(received).toEqual(['hello', 'world']);
+
+    unsub();
+    await adapter.publish('chan', 'after-unsub');
+    expect(received).toEqual(['hello', 'world']);
+  });
+
+  it('persistence survives close and re-create', async () => {
+    const p1 = makePayload('x');
+    const p2 = makePayload('y');
+
+    const adapter1 = createLocalAdapter({ type: 'local', dataDir });
+    await adapter1.enqueue('persist-q', p1);
+    await adapter1.enqueue('persist-q', p2);
+    await adapter1.close();
+
+    const adapter2 = createLocalAdapter({ type: 'local', dataDir });
+    expect(await adapter2.length('persist-q')).toBe(2);
+    expect(await adapter2.dequeue('persist-q')).toEqual(p1);
+    expect(await adapter2.dequeue('persist-q')).toEqual(p2);
+    await adapter2.close();
+  });
+});