Add backend unit/integration tests, Playwright e2e tests, README, cookie Secure fix

backend/tests/integration/items.integration.test.ts

@@ -0,0 +1,66 @@
+import request from 'supertest';
+import app from '../../src/app';
+import { pool } from '../../src/db';
+import { resetDb, closeDb } from './setup/testDb';
+
+beforeEach(async () => {
+  await resetDb();
+});
+
+afterAll(async () => {
+  await pool.end();
+  await closeDb();
+});
+
+describe('GET /api/items', () => {
+  it('returns an empty array when there are no items', async () => {
+    const res = await request(app).get('/api/items');
+    expect(res.status).toBe(200);
+    expect(res.body).toEqual([]);
+  });
+
+  it('returns items with an empty images array when none are attached', async () => {
+    await pool.query(
+      `INSERT INTO items (name, description, price_cents) VALUES ('Vintage Lamp', 'A one-of-a-kind lamp.', 4500)`
+    );
+    const res = await request(app).get('/api/items');
+    expect(res.status).toBe(200);
+    expect(res.body).toHaveLength(1);
+    expect(res.body[0]).toMatchObject({
+      name: 'Vintage Lamp',
+      price_cents: 4500,
+      status: 'available',
+      images: []
+    });
+  });
+
+  it('returns 404 for a nonexistent item', async () => {
+    const res = await request(app).get('/api/items/99999');
+    expect(res.status).toBe(404);
+  });
+});
+
+describe('demo checkout', () => {
+  it('marks an available item as sold', async () => {
+    const { rows } = await pool.query(
+      `INSERT INTO items (name, price_cents) VALUES ('Test Item', 1000) RETURNING id`
+    );
+    const itemId = rows[0].id;
+
+    const res = await request(app).post(`/api/checkout/demo/${itemId}/purchase`);
+    expect(res.status).toBe(200);
+    expect(res.body.status).toBe('sold');
+
+    const check = await request(app).get(`/api/items/${itemId}`);
+    expect(check.body.status).toBe('sold');
+  });
+
+  it('refuses to sell an item that is already sold', async () => {
+    const { rows } = await pool.query(
+      `INSERT INTO items (name, price_cents, status) VALUES ('Already Sold', 1000, 'sold') RETURNING id`
+    );
+    const itemId = rows[0].id;
+    const res = await request(app).post(`/api/checkout/demo/${itemId}/purchase`);
+    expect(res.status).toBe(409);
+  });
+});