Belajar QA Automation Engineer - Test Data & Fixtures

#Pendahuluan

Setelah di episode 9 kita membahas E2E strategy, pada episode ini kita mendalami komponen yang sering diabaikan: test data. Test data yang buruk menyebabkan flaky tests, false positives, dan maintenance nightmare.

#Test Data Strategies

#Static Data

typescript

// fixtures/users.ts
export const users = {
  valid: {
    name: 'John Doe',
    email: 'john@test.com',
    password: 'SecurePass123!'
  },
  invalid: {
    name: '',
    email: 'not-an-email',
    password: '1'
  },
  expiredToken: {
    name: 'Expired User',
    token: 'expired-token-value'
  }
};

#Dynamic Data (Factories)

typescript

// factories/userFactory.ts
let userCounter = 0;
 
export function createUser(overrides = {}) {
  userCounter++;
  return {
    name: `Test User ${userCounter}`,
    email: `user${userCounter}@test.com`,
    password: 'TestPass123!',
    ...overrides
  };
}
 
export function createAdmin(overrides = {}) {
  return createUser({
    name: 'Admin User',
    email: `admin${Date.now()}@test.com`,
    role: 'admin',
    ...overrides
  });
}

#Playwright Fixtures

typescript

// fixtures.ts
import { test as base } from '@playwright/test';
import { createUser } from './factories/userFactory';
 
type TestFixtures = {
  user: ReturnType<typeof createUser>;
  authenticatedPage: any;
};
 
export const test = base.extend<TestFixtures>({
  user: async ({}, use) => {
    const user = createUser();
    // Setup: create user in database
    await createTestUser(user);
    await use(user);
    // Cleanup: remove user
    await deleteTestUser(user.email);
  },
 
  authenticatedPage: async ({ page, user }, use) => {
    // Auto-login
    await page.goto('/login');
    await page.fill('#email', user.email);
    await page.fill('#password', user.password);
    await page.click('#login-button');
    await expect(page).toHaveURL('/dashboard');
    await use(page);
  },
});

#Data Seeding

typescript

// seed.ts
import { PrismaClient } from '@prisma/client';
 
const prisma = new PrismaClient();
 
export async function seedTestData() {
  // Create test users
  await prisma.user.createMany({
    data: [
      { name: 'User 1', email: 'user1@test.com', password: 'hashed' },
      { name: 'User 2', email: 'user2@test.com', password: 'hashed' },
    ]
  });
 
  // Create test products
  await prisma.product.createMany({
    data: [
      { name: 'Product A', price: 29.99 },
      { name: 'Product B', price: 49.99 },
    ]
  });
}
 
// Cleanup
export async function cleanupTestData() {
  await prisma.user.deleteMany({ where: { email: { contains: '@test.com' } } });
  await prisma.product.deleteMany();
}

#Isolation Strategies

text

Data Isolation Options:
├── Per-test: buat & hapus data di setiap test (slow tapi isolated)
├── Per-describe: buat data sekali, cleanup setelah suite
├── Per-run: seed sekali di awal, reset antar run
├── Database transactions: rollback setelah test
└── Separate database: test DB terpisah dari production

Warning

Jangan pernah pakai production data untuk testing. Gunakan test data yang terisolasi dan bisa di-reproduce.

#Praktik: Test Data Setup

typescript

// Setup test data
test.beforeAll(async () => {
  await seedTestData();
});
 
// Cleanup
test.afterAll(async () => {
  await cleanupTestData();
});
 
// Per-test cleanup
test.afterEach(async ({ page }) => {
  await page.context().clearCookies();
  await page.evaluate(() => localStorage.clear());
});

#Penutup

Static data: predictable, mudah di-debug.
Dynamic data (factories): unique, tidak collision antar test.
Playwright fixtures: auto-setup dan cleanup.
Isolation: per-test atau per-describe, tergantung kebutuhan.

Di episode 11 selanjutnya kita akan membahas CI/CD integration — menjalankan test di CI, parallelization, dan reporting. Sampai jumpa di episode 11!