# ORIGIN_TESTING_STRATEGY.md

## 📋 RÉSUMÉ EXÉCUTIF

Ce document définit la stratégie de testing complète et définitive pour la plateforme Veza. Il couvre tous les types de tests (unit, integration, E2E, performance, security, load) avec couverture minimale 80%, outils standardisés, processus CI/CD automatisé, et méthodologies (TDD, BDD). Cette stratégie garantit qualité production, réduction bugs, et confiance déploiement continu sur 24 mois.

## 🎯 OBJECTIFS

### Objectif Principal
Établir une culture de testing exhaustive avec couverture ≥ 80%, automatisation complète CI/CD, et détection précoce de régressions pour assurer déploiements production sans risque et maintenance long-terme facilitée.

### Objectifs Secondaires
- Réduire taux de bugs en production (< 0.1% des releases)
- Accélérer feedback loop (tests < 10 min en CI/CD)
- Faciliter refactoring avec confiance (tests comme safety net)
- Documenter comportement attendu via tests
- Détecter problèmes performance avant production

## 📖 TABLE DES MATIÈRES

1. [Testing Philosophy](#1-testing-philosophy)
2. [Test Types & Coverage](#2-test-types--coverage)
3. [Unit Testing](#3-unit-testing)
4. [Integration Testing](#4-integration-testing)
5. [End-to-End Testing](#5-end-to-end-testing)
6. [Performance Testing](#6-performance-testing)
7. [Security Testing](#7-security-testing)
8. [Load & Stress Testing](#8-load--stress-testing)
9. [Test Data Management](#9-test-data-management)
10. [CI/CD Pipeline Testing](#10-cicd-pipeline-testing)
11. [Test Automation](#11-test-automation)
12. [Quality Gates](#12-quality-gates)

## 🔒 RÈGLES IMMUABLES

1. **Coverage Minimum**: 80% line coverage pour nouveau code - CI/CD bloque si < 80%
2. **Test Before Merge**: Aucun PR mergé sans tests - aucune exception
3. **Test Isolation**: Chaque test indépendant (no shared state, no order dependency)
4. **Fast Feedback**: Tests unitaires < 2 min, integration < 5 min, E2E < 10 min
5. **Deterministic**: Tests 100% reproductibles (no flaky tests tolérés)
6. **Test Data**: Fixtures isolées, cleanup automatique (no test pollution)
7. **Mocking**: Dependencies externes mockées (DB, APIs, time)
8. **Regression**: Bug fix = nouveau test (prevent recurrence)
9. **Documentation**: Tests servent de documentation (readable, self-explanatory)
10. **Performance**: Tests de performance en CI/CD (regression detection)

## 1. TESTING PHILOSOPHY

### 1.1 Testing Pyramid

```
         ╱╲
        ╱  ╲
       ╱ E2E ╲                  10% - Slow, Brittle, High Cost
      ╱────────╲
     ╱          ╲
    ╱ Integration ╲             20% - Medium Speed, Medium Cost
   ╱──────────────╲
  ╱                ╲
 ╱   Unit Tests     ╲           70% - Fast, Reliable, Low Cost
╱────────────────────╲
```

**Distribution**:
- **Unit Tests (70%)**: Fast, isolated, test single functions/methods
- **Integration Tests (20%)**: Medium speed, test component interactions
- **E2E Tests (10%)**: Slow, test complete user flows

### 1.2 Testing Principles

**F.I.R.S.T Principles**:
- **Fast**: Tests execute quickly (unit < 100ms, all tests < 10min)
- **Independent**: No test depends on another (can run in any order)
- **Repeatable**: Same result every time (deterministic)
- **Self-Validating**: Pass/fail clear (no manual inspection)
- **Timely**: Written with code (not after, preferably before - TDD)

**Test Qualities**:
- **Readable**: Anyone can understand what's being tested
- **Maintainable**: Easy to update when requirements change
- **Trustworthy**: No false positives/negatives (no flaky tests)
- **Comprehensive**: Cover happy path + edge cases + error cases

### 1.3 TDD (Test-Driven Development)

**Red-Green-Refactor Cycle**:
```
1. 🔴 RED: Write failing test first
2. 🟢 GREEN: Write minimum code to pass
3. 🔵 REFACTOR: Clean up code while tests pass
4. Repeat
```

**Example Flow**:
```go
// 1. RED - Write failing test
func TestCreateUser_Success(t *testing.T) {
    service := NewUserService()
    user := &User{Email: "test@example.com"}
    
    err := service.CreateUser(user)
    assert.NoError(t, err)
    assert.NotEmpty(t, user.ID)
}
// Test fails - CreateUser doesn't exist yet

// 2. GREEN - Implement minimum code
func (s *UserService) CreateUser(user *User) error {
    user.ID = uuid.New().String()
    return nil
}
// Test passes

// 3. REFACTOR - Improve code
func (s *UserService) CreateUser(user *User) error {
    if err := validateEmail(user.Email); err != nil {
        return err
    }
    user.ID = uuid.New().String()
    return s.repo.Save(user)
}
// Tests still pass
```

## 2. TEST TYPES & COVERAGE

### 2.1 Coverage Requirements

| Test Type | Coverage Target | Execution Time | Frequency |
|-----------|----------------|----------------|-----------|
| **Unit Tests** | ≥ 80% line coverage | < 2 min | Every commit |
| **Integration Tests** | ≥ 70% API endpoints | < 5 min | Every commit |
| **E2E Tests** | ≥ 50% critical flows | < 10 min | Every commit (smoke), Full nightly |
| **Performance Tests** | 100% critical endpoints | < 15 min | Nightly + Pre-release |
| **Security Tests** | 100% OWASP Top 10 | < 20 min | Weekly + Pre-release |
| **Load Tests** | 100% production scenarios | 30-60 min | Weekly + Pre-release |

### 2.2 Coverage Metrics

**Tracked Metrics**:
- **Line Coverage**: % of lines executed during tests
- **Branch Coverage**: % of conditional branches tested
- **Function Coverage**: % of functions called
- **Statement Coverage**: % of statements executed

**Tools**:
- **Go**: `go test -cover`, `gocov`
- **Rust**: `cargo tarpaulin`
- **TypeScript**: `vitest --coverage` (c8)

**Example Coverage Report**:
```bash
# Go
go test ./... -coverprofile=coverage.out
go tool cover -html=coverage.out -o coverage.html

# Coverage output:
# internal/services/user_service.go:     CreateUser           85.7%
# internal/services/track_service.go:    UploadTrack          92.3%
# internal/handlers/auth_handlers.go:    Login                78.5%  ⚠️ Below 80%
```

## 3. UNIT TESTING

### 3.1 Unit Test Structure (AAA Pattern)

**Arrange-Act-Assert**:
```go
func TestUserService_CreateUser_Success(t *testing.T) {
    // ARRANGE - Setup test data and dependencies
    mockRepo := &MockUserRepository{}
    mockRepo.CreateFunc = func(user *User) error {
        return nil
    }
    service := NewUserService(mockRepo)
    user := &User{
        Email:    "test@example.com",
        Username: "testuser",
    }
    
    // ACT - Execute the function under test
    err := service.CreateUser(user)
    
    // ASSERT - Verify the outcome
    assert.NoError(t, err)
    assert.NotEmpty(t, user.ID)
    assert.NotEmpty(t, user.CreatedAt)
}
```

### 3.2 Test Naming Convention

**Format**: `Test<FunctionName>_<Scenario>_<ExpectedBehavior>`

**Examples**:
```go
// ✅ GOOD - Descriptive test names
func TestCreateUser_ValidData_Success(t *testing.T) { }
func TestCreateUser_DuplicateEmail_ReturnsConflictError(t *testing.T) { }
func TestCreateUser_InvalidEmail_ReturnsValidationError(t *testing.T) { }
func TestGetUserByID_ExistingUser_ReturnsUser(t *testing.T) { }
func TestGetUserByID_NonExistentUser_ReturnsNotFoundError(t *testing.T) { }

// ❌ BAD - Unclear test names
func TestCreateUser(t *testing.T) { }
func TestUser(t *testing.T) { }
func TestSuccess(t *testing.T) { }
```

### 3.3 Table-Driven Tests

```go
func TestValidateEmail(t *testing.T) {
    tests := []struct {
        name    string
        email   string
        wantErr bool
        errMsg  string
    }{
        {
            name:    "valid email",
            email:   "user@example.com",
            wantErr: false,
        },
        {
            name:    "valid email with subdomain",
            email:   "user@mail.example.com",
            wantErr: false,
        },
        {
            name:    "missing @ symbol",
            email:   "userexample.com",
            wantErr: true,
            errMsg:  "invalid email format",
        },
        {
            name:    "missing domain",
            email:   "user@",
            wantErr: true,
            errMsg:  "invalid email format",
        },
        {
            name:    "empty string",
            email:   "",
            wantErr: true,
            errMsg:  "email is required",
        },
    }
    
    for _, tt := range tests {
        t.Run(tt.name, func(t *testing.T) {
            err := validateEmail(tt.email)
            
            if tt.wantErr {
                assert.Error(t, err)
                if tt.errMsg != "" {
                    assert.Contains(t, err.Error(), tt.errMsg)
                }
            } else {
                assert.NoError(t, err)
            }
        })
    }
}
```

### 3.4 Mocking (Go)

**Interface-Based Mocking**:
```go
// Production interface
type UserRepository interface {
    Create(user *User) error
    GetByID(id string) (*User, error)
    GetByEmail(email string) (*User, error)
    Update(user *User) error
    Delete(id string) error
}

// Mock implementation
type MockUserRepository struct {
    CreateFunc    func(user *User) error
    GetByIDFunc   func(id string) (*User, error)
    GetByEmailFunc func(email string) (*User, error)
    UpdateFunc    func(user *User) error
    DeleteFunc    func(id string) error
}

func (m *MockUserRepository) Create(user *User) error {
    if m.CreateFunc != nil {
        return m.CreateFunc(user)
    }
    return nil
}

func (m *MockUserRepository) GetByID(id string) (*User, error) {
    if m.GetByIDFunc != nil {
        return m.GetByIDFunc(id)
    }
    return nil, errors.New("not implemented")
}

// Test usage
func TestUserService_CreateUser(t *testing.T) {
    mockRepo := &MockUserRepository{
        CreateFunc: func(user *User) error {
            user.ID = "mock-id-123"
            return nil
        },
        GetByEmailFunc: func(email string) (*User, error) {
            return nil, gorm.ErrRecordNotFound // Simulate no existing user
        },
    }
    
    service := NewUserService(mockRepo)
    user := &User{Email: "test@example.com"}
    
    err := service.CreateUser(user)
    assert.NoError(t, err)
    assert.Equal(t, "mock-id-123", user.ID)
}
```

### 3.5 Testing Async Code (TypeScript)

```typescript
import { describe, it, expect, vi } from 'vitest';

describe('UserService', () => {
  it('should create user successfully', async () => {
    // ARRANGE
    const mockRepo = {
      create: vi.fn().mockResolvedValue({ id: 'user-123' }),
      getByEmail: vi.fn().mockResolvedValue(null),
    };
    const service = new UserService(mockRepo);
    const user = { email: 'test@example.com', username: 'testuser' };
    
    // ACT
    const result = await service.createUser(user);
    
    // ASSERT
    expect(result).toHaveProperty('id');
    expect(mockRepo.create).toHaveBeenCalledWith(
      expect.objectContaining({ email: 'test@example.com' })
    );
  });
  
  it('should handle errors gracefully', async () => {
    // ARRANGE
    const mockRepo = {
      create: vi.fn().mockRejectedValue(new Error('Database error')),
      getByEmail: vi.fn().mockResolvedValue(null),
    };
    const service = new UserService(mockRepo);
    
    // ACT & ASSERT
    await expect(service.createUser({ email: 'test@example.com' }))
      .rejects
      .toThrow('Database error');
  });
});
```

## 4. INTEGRATION TESTING

### 4.1 API Integration Tests (Go)

**Test with Real Database (Testcontainers)**:
```go
import (
    "testing"
    "github.com/testcontainers/testcontainers-go"
    "github.com/testcontainers/testcontainers-go/wait"
)

func setupTestDB(t *testing.T) *gorm.DB {
    ctx := context.Background()
    
    // Start PostgreSQL container
    req := testcontainers.ContainerRequest{
        Image:        "postgres:15-alpine",
        ExposedPorts: []string{"5432/tcp"},
        Env: map[string]string{
            "POSTGRES_DB":       "test_db",
            "POSTGRES_USER":     "test",
            "POSTGRES_PASSWORD": "test",
        },
        WaitingFor: wait.ForLog("database system is ready to accept connections"),
    }
    
    container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
        ContainerRequest: req,
        Started:          true,
    })
    require.NoError(t, err)
    
    t.Cleanup(func() {
        container.Terminate(ctx)
    })
    
    // Get connection string
    host, _ := container.Host(ctx)
    port, _ := container.MappedPort(ctx, "5432")
    dsn := fmt.Sprintf("host=%s port=%s user=test password=test dbname=test_db sslmode=disable", host, port.Port())
    
    // Connect and migrate
    db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{})
    require.NoError(t, err)
    
    db.AutoMigrate(&User{}, &Track{}, &Playlist{})
    
    return db
}

func TestUserAPI_CreateUser_Integration(t *testing.T) {
    // ARRANGE
    db := setupTestDB(t)
    router := setupRouter(db)
    
    payload := map[string]interface{}{
        "email":    "test@example.com",
        "username": "testuser",
        "password": "SecurePass123!",
    }
    body, _ := json.Marshal(payload)
    
    req := httptest.NewRequest("POST", "/api/v1/users", bytes.NewReader(body))
    req.Header.Set("Content-Type", "application/json")
    w := httptest.NewRecorder()
    
    // ACT
    router.ServeHTTP(w, req)
    
    // ASSERT
    assert.Equal(t, 201, w.Code)
    
    var response map[string]interface{}
    json.Unmarshal(w.Body.Bytes(), &response)
    
    assert.Contains(t, response, "data")
    userData := response["data"].(map[string]interface{})
    assert.Equal(t, "test@example.com", userData["email"])
    assert.NotEmpty(t, userData["id"])
    
    // Verify in database
    var user User
    err := db.First(&user, "email = ?", "test@example.com").Error
    assert.NoError(t, err)
    assert.Equal(t, "testuser", user.Username)
}
```

### 4.2 Database Integration Tests (Rust)

```rust
use sqlx::PgPool;

#[sqlx::test]
async fn test_create_user(pool: PgPool) -> sqlx::Result<()> {
    // ARRANGE
    let user = User {
        id: Uuid::new_v4(),
        email: "test@example.com".to_string(),
        username: "testuser".to_string(),
        password_hash: "hashed_password".to_string(),
    };
    
    // ACT
    let result = sqlx::query!(
        "INSERT INTO users (id, email, username, password_hash) VALUES ($1, $2, $3, $4)",
        user.id,
        user.email,
        user.username,
        user.password_hash
    )
    .execute(&pool)
    .await?;
    
    // ASSERT
    assert_eq!(result.rows_affected(), 1);
    
    // Verify user exists
    let fetched_user = sqlx::query_as!(
        User,
        "SELECT id, email, username, password_hash, created_at FROM users WHERE id = $1",
        user.id
    )
    .fetch_one(&pool)
    .await?;
    
    assert_eq!(fetched_user.email, "test@example.com");
    assert_eq!(fetched_user.username, "testuser");
    
    Ok(())
}
```

### 4.3 API Contract Testing

**OpenAPI Schema Validation**:
```typescript
import { describe, it, expect } from 'vitest';
import { validateAgainstSchema } from './openapi-validator';

describe('API Contract Tests', () => {
  it('POST /users response matches OpenAPI schema', async () => {
    const response = await fetch('http://localhost:8080/api/v1/users', {
      method: 'POST',
      body: JSON.stringify({
        email: 'test@example.com',
        username: 'testuser',
        password: 'SecurePass123!',
      }),
      headers: { 'Content-Type': 'application/json' },
    });
    
    const data = await response.json();
    
    // Validate against OpenAPI schema
    const validation = validateAgainstSchema(
      'POST',
      '/users',
      201,
      data
    );
    
    expect(validation.valid).toBe(true);
    expect(validation.errors).toHaveLength(0);
  });
});
```

## 5. END-TO-END TESTING

### 5.1 E2E Testing with Playwright

**Setup**:
```typescript
// playwright.config.ts
import { defineConfig } from '@playwright/test';

export default defineConfig({
  testDir: './tests/e2e',
  timeout: 30000,
  retries: 2,
  use: {
    baseURL: 'http://localhost:3000',
    screenshot: 'only-on-failure',
    video: 'retain-on-failure',
    trace: 'on-first-retry',
  },
  projects: [
    { name: 'chromium', use: { browserName: 'chromium' } },
    { name: 'firefox', use: { browserName: 'firefox' } },
    { name: 'webkit', use: { browserName: 'webkit' } },
  ],
  webServer: {
    command: 'npm run dev',
    port: 3000,
    reuseExistingServer: !process.env.CI,
  },
});
```

**E2E Test Example**:
```typescript
import { test, expect } from '@playwright/test';

test.describe('User Registration Flow', () => {
  test('should register new user successfully', async ({ page }) => {
    // Navigate to registration page
    await page.goto('/register');
    
    // Fill registration form
    await page.fill('input[name="email"]', 'newuser@example.com');
    await page.fill('input[name="username"]', 'newuser');
    await page.fill('input[name="password"]', 'SecurePass123!');
    await page.fill('input[name="confirmPassword"]', 'SecurePass123!');
    
    // Submit form
    await page.click('button[type="submit"]');
    
    // Wait for redirect to dashboard
    await page.waitForURL('/dashboard');
    
    // Verify user is logged in
    await expect(page.locator('text=Welcome, newuser')).toBeVisible();
    
    // Verify email verification notice
    await expect(page.locator('text=Please verify your email')).toBeVisible();
  });
  
  test('should show validation errors for invalid data', async ({ page }) => {
    await page.goto('/register');
    
    // Submit empty form
    await page.click('button[type="submit"]');
    
    // Verify error messages
    await expect(page.locator('text=Email is required')).toBeVisible();
    await expect(page.locator('text=Username is required')).toBeVisible();
    await expect(page.locator('text=Password is required')).toBeVisible();
  });
});

test.describe('Track Upload Flow', () => {
  test('should upload track successfully', async ({ page }) => {
    // Login first
    await page.goto('/login');
    await page.fill('input[name="email"]', 'creator@example.com');
    await page.fill('input[name="password"]', 'password123');
    await page.click('button[type="submit"]');
    await page.waitForURL('/dashboard');
    
    // Navigate to upload page
    await page.goto('/upload');
    
    // Upload file
    await page.setInputFiles('input[type="file"]', './fixtures/test-track.mp3');
    
    // Fill track details
    await page.fill('input[name="title"]', 'Test Track');
    await page.fill('textarea[name="description"]', 'This is a test track');
    await page.selectOption('select[name="genre"]', 'electronic');
    
    // Submit
    await page.click('button[type="submit"]');
    
    // Wait for processing message
    await expect(page.locator('text=Processing your track')).toBeVisible();
    
    // Verify redirect to track page
    await page.waitForURL(/\/tracks\/[a-z0-9-]+/, { timeout: 60000 });
    
    // Verify track details
    await expect(page.locator('h1', { hasText: 'Test Track' })).toBeVisible();
  });
});
```

### 5.2 Visual Regression Testing

```typescript
import { test, expect } from '@playwright/test';

test('homepage visual regression', async ({ page }) => {
  await page.goto('/');
  
  // Take screenshot and compare with baseline
  await expect(page).toHaveScreenshot('homepage.png', {
    fullPage: true,
    maxDiffPixels: 100, // Allow small differences
  });
});

test('user profile visual regression', async ({ page }) => {
  await page.goto('/users/johndoe');
  
  // Hide dynamic elements (timestamps, play counts)
  await page.locator('.last-activity').evaluate(el => el.style.visibility = 'hidden');
  await page.locator('.play-count').evaluate(el => el.style.visibility = 'hidden');
  
  await expect(page).toHaveScreenshot('user-profile.png');
});
```

## 6. PERFORMANCE TESTING

### 6.1 Performance Tests with k6

**Load Testing Script**:
```javascript
// k6-load-test.js
import http from 'k6/http';
import { check, sleep } from 'k6';

export const options = {
  stages: [
    { duration: '2m', target: 100 },  // Ramp up to 100 users
    { duration: '5m', target: 100 },  // Stay at 100 users
    { duration: '2m', target: 200 },  // Ramp up to 200 users
    { duration: '5m', target: 200 },  // Stay at 200 users
    { duration: '2m', target: 0 },    // Ramp down to 0
  ],
  thresholds: {
    http_req_duration: ['p(95)<100'], // 95% of requests < 100ms
    http_req_failed: ['rate<0.01'],   // < 1% failure rate
  },
};

export default function () {
  // Test GET /tracks
  const tracksRes = http.get('https://api.veza.app/v1/tracks');
  check(tracksRes, {
    'status is 200': (r) => r.status === 200,
    'response time < 100ms': (r) => r.timings.duration < 100,
  });
  
  sleep(1);
  
  // Test GET /tracks/{id}
  const trackRes = http.get('https://api.veza.app/v1/tracks/track-123');
  check(trackRes, {
    'status is 200': (r) => r.status === 200,
    'response time < 50ms': (r) => r.timings.duration < 50,
  });
  
  sleep(1);
}
```

**Run k6 Tests**:
```bash
# Local test
k6 run k6-load-test.js

# Cloud test (k6 Cloud)
k6 cloud k6-load-test.js

# Output to InfluxDB for Grafana dashboard
k6 run --out influxdb=http://localhost:8086/k6 k6-load-test.js
```

### 6.2 Database Performance Tests

```go
func BenchmarkGetUserByID(b *testing.B) {
    db := setupTestDB(b)
    repo := NewUserRepository(db)
    
    // Create test user
    user := &User{Email: "bench@example.com", Username: "benchuser"}
    repo.Create(user)
    
    b.ResetTimer()
    
    for i := 0; i < b.N; i++ {
        _, err := repo.GetByID(user.ID)
        if err != nil {
            b.Fatal(err)
        }
    }
}

func BenchmarkGetUserByEmail(b *testing.B) {
    db := setupTestDB(b)
    repo := NewUserRepository(db)
    
    user := &User{Email: "bench@example.com", Username: "benchuser"}
    repo.Create(user)
    
    b.ResetTimer()
    
    for i := 0; i < b.N; i++ {
        _, err := repo.GetByEmail("bench@example.com")
        if err != nil {
            b.Fatal(err)
        }
    }
}

// Run benchmarks
// go test -bench=. -benchmem
// BenchmarkGetUserByID-8     50000   25000 ns/op   1024 B/op   15 allocs/op
// BenchmarkGetUserByEmail-8  45000   28000 ns/op   1152 B/op   17 allocs/op
```

## 7. SECURITY TESTING

### 7.1 SAST (Static Application Security Testing)

**Tools**:
- **Go**: `gosec`, `nancy` (dependency scanning)
- **Rust**: `cargo audit`, `cargo-geiger`
- **TypeScript**: `npm audit`, `snyk`

**CI/CD Integration**:
```yaml
# .github/workflows/security-scan.yml
name: Security Scan

on: [push, pull_request]

jobs:
  security:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      
      # Go security scan
      - name: Run gosec
        uses: securego/gosec@master
        with:
          args: '-fmt=sarif -out=results.sarif ./...'
      
      # Rust dependency audit
      - name: Cargo audit
        run: cargo audit
      
      # Node.js audit
      - name: NPM audit
        run: npm audit --production
      
      # Snyk scan
      - name: Run Snyk
        uses: snyk/actions/node@master
        env:
          SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }}
```

### 7.2 DAST (Dynamic Application Security Testing)

**OWASP ZAP Automated Scan**:
```bash
# Start application
docker-compose up -d

# Run ZAP baseline scan
docker run -t owasp/zap2docker-stable zap-baseline.py \
  -t https://staging.veza.app \
  -r zap-report.html

# Run ZAP full scan
docker run -t owasp/zap2docker-stable zap-full-scan.py \
  -t https://staging.veza.app \
  -r zap-full-report.html
```

### 7.3 Penetration Testing

**Automated Tests**:
```typescript
import { test, expect } from '@playwright/test';

test.describe('Security Tests', () => {
  test('should prevent SQL injection', async ({ request }) => {
    // Try SQL injection in email field
    const response = await request.post('/api/v1/auth/login', {
      data: {
        email: "admin' OR '1'='1",
        password: "anything",
      },
    });
    
    // Should return 400 validation error, not 200
    expect(response.status()).toBe(400);
    
    const data = await response.json();
    expect(data.error.code).toBe(4001); // Invalid format
  });
  
  test('should prevent XSS', async ({ page }) => {
    await page.goto('/register');
    
    // Try XSS in username field
    await page.fill('input[name="username"]', '<script>alert("XSS")</script>');
    await page.fill('input[name="email"]', 'test@example.com');
    await page.fill('input[name="password"]', 'SecurePass123!');
    await page.click('button[type="submit"]');
    
    // Should show validation error
    await expect(page.locator('text=Invalid username format')).toBeVisible();
  });
  
  test('should enforce rate limiting', async ({ request }) => {
    // Send 10 requests quickly
    const promises = Array.from({ length: 10 }, () =>
      request.post('/api/v1/auth/login', {
        data: { email: 'test@example.com', password: 'wrong' },
      })
    );
    
    const responses = await Promise.all(promises);
    
    // At least one should be rate limited (429)
    const rateLimited = responses.filter(r => r.status() === 429);
    expect(rateLimited.length).toBeGreaterThan(0);
  });
});
```

## 8. LOAD & STRESS TESTING

### 8.1 Load Testing Scenarios

**Scenario 1: Normal Load (1000 concurrent users)**:
```javascript
// k6-normal-load.js
export const options = {
  vus: 1000,
  duration: '10m',
  thresholds: {
    http_req_duration: ['p(95)<100', 'p(99)<200'],
    http_req_failed: ['rate<0.01'],
  },
};

export default function () {
  // Simulate realistic user behavior
  http.get('https://api.veza.app/v1/tracks');
  sleep(Math.random() * 3 + 2); // 2-5s
  
  http.get('https://api.veza.app/v1/tracks/track-123');
  sleep(Math.random() * 5 + 5); // 5-10s
  
  http.post('https://api.veza.app/v1/tracks/track-123/play');
  sleep(Math.random() * 180 + 60); // 1-4min (listening to track)
}
```

**Scenario 2: Peak Load (5000 concurrent users)**:
```javascript
export const options = {
  stages: [
    { duration: '5m', target: 5000 },
    { duration: '10m', target: 5000 },
    { duration: '5m', target: 0 },
  ],
};
```

**Scenario 3: Stress Test (Find breaking point)**:
```javascript
export const options = {
  stages: [
    { duration: '2m', target: 1000 },
    { duration: '5m', target: 1000 },
    { duration: '2m', target: 2000 },
    { duration: '5m', target: 2000 },
    { duration: '2m', target: 5000 },
    { duration: '5m', target: 5000 },
    { duration: '2m', target: 10000 }, // Push to breaking point
    { duration: '5m', target: 10000 },
    { duration: '10m', target: 0 },
  ],
};
```

### 8.2 Spike Testing

```javascript
// k6-spike-test.js
export const options = {
  stages: [
    { duration: '1m', target: 100 },    // Normal load
    { duration: '10s', target: 10000 }, // Sudden spike
    { duration: '3m', target: 10000 },  // Stay at spike
    { duration: '10s', target: 100 },   // Drop back
    { duration: '1m', target: 100 },    // Recover
  ],
};
```

## 9. TEST DATA MANAGEMENT

### 9.1 Test Fixtures

**Go Test Fixtures**:
```go
// testdata/fixtures.go
package testdata

func CreateTestUser() *User {
    return &User{
        ID:       uuid.New().String(),
        Email:    "test@example.com",
        Username: "testuser",
        Role:     "user",
    }
}

func CreateTestTrack() *Track {
    return &Track{
        ID:              uuid.New().String(),
        Title:           "Test Track",
        Artist:          "Test Artist",
        Genre:           "electronic",
        DurationSeconds: 240,
    }
}
```

**TypeScript Fixtures**:
```typescript
// tests/fixtures/users.ts
export const testUsers = {
  normalUser: {
    id: 'user-123',
    email: 'user@example.com',
    username: 'testuser',
    role: 'user',
  },
  premiumUser: {
    id: 'user-456',
    email: 'premium@example.com',
    username: 'premiumuser',
    role: 'premium',
  },
  admin: {
    id: 'user-789',
    email: 'admin@example.com',
    username: 'admin',
    role: 'admin',
  },
};
```

### 9.2 Test Database Seeding

```sql
-- tests/seed.sql
-- Seed database with test data

INSERT INTO users (id, email, username, password_hash, role)
VALUES 
  ('user-123', 'user@example.com', 'testuser', 'hashed_password', 'user'),
  ('user-456', 'premium@example.com', 'premiumuser', 'hashed_password', 'premium'),
  ('user-789', 'admin@example.com', 'admin', 'hashed_password', 'admin');

INSERT INTO tracks (id, user_id, title, artist, genre, duration_seconds)
VALUES
  ('track-123', 'user-123', 'Test Track 1', 'Test Artist', 'electronic', 240),
  ('track-456', 'user-123', 'Test Track 2', 'Test Artist', 'rock', 180),
  ('track-789', 'user-456', 'Premium Track', 'Premium Artist', 'jazz', 300);
```

### 9.3 Cleanup Strategy

```go
func TestMain(m *testing.M) {
    // Setup
    db := setupTestDB()
    
    // Run tests
    code := m.Run()
    
    // Cleanup
    db.Exec("TRUNCATE TABLE users CASCADE")
    db.Exec("TRUNCATE TABLE tracks CASCADE")
    db.Exec("TRUNCATE TABLE playlists CASCADE")
    
    os.Exit(code)
}

func setupTest(t *testing.T, db *gorm.DB) {
    t.Cleanup(func() {
        db.Exec("DELETE FROM users")
        db.Exec("DELETE FROM tracks")
    })
}
```

## 10. CI/CD PIPELINE TESTING

### 10.1 GitHub Actions Workflow

```yaml
# .github/workflows/test.yml
name: Test Suite

on:
  push:
    branches: [main, develop]
  pull_request:
    branches: [main, develop]

jobs:
  unit-tests:
    runs-on: ubuntu-latest
    timeout-minutes: 10
    
    steps:
      - uses: actions/checkout@v3
      
      # Go tests
      - name: Setup Go
        uses: actions/setup-go@v4
        with:
          go-version: '1.21'
      
      - name: Run Go tests
        run: |
          cd veza-backend-api
          go test ./... -v -coverprofile=coverage.out
          go tool cover -func=coverage.out
      
      - name: Check coverage
        run: |
          coverage=$(go tool cover -func=coverage.out | grep total | awk '{print $3}' | sed 's/%//')
          if (( $(echo "$coverage < 80" | bc -l) )); then
            echo "Coverage $coverage% is below 80%"
            exit 1
          fi
      
      # Rust tests
      - name: Setup Rust
        uses: actions-rs/toolchain@v1
        with:
          toolchain: stable
      
      - name: Run Rust tests
        run: |
          cd veza-chat-server
          cargo test --all-features
      
      # TypeScript tests
      - name: Setup Node
        uses: actions/setup-node@v3
        with:
          node-version: '20'
      
      - name: Run TypeScript tests
        run: |
          cd apps/web
          npm ci
          npm run test -- --coverage
      
      - name: Upload coverage
        uses: codecov/codecov-action@v3
        with:
          files: ./coverage/coverage-final.json
  
  integration-tests:
    runs-on: ubuntu-latest
    timeout-minutes: 15
    
    services:
      postgres:
        image: postgres:15-alpine
        env:
          POSTGRES_PASSWORD: postgres
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
      
      redis:
        image: redis:7-alpine
        options: >-
          --health-cmd "redis-cli ping"
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
    
    steps:
      - uses: actions/checkout@v3
      
      - name: Run integration tests
        env:
          DATABASE_URL: postgres://postgres:postgres@localhost:5432/test_db
          REDIS_URL: redis://localhost:6379
        run: |
          cd veza-backend-api
          go test ./tests/integration/... -v
  
  e2e-tests:
    runs-on: ubuntu-latest
    timeout-minutes: 20
    
    steps:
      - uses: actions/checkout@v3
      
      - name: Install Playwright
        run: |
          cd apps/web
          npm ci
          npx playwright install --with-deps
      
      - name: Start services
        run: docker-compose up -d
      
      - name: Wait for services
        run: |
          timeout 60 bash -c 'until curl -f http://localhost:8080/health; do sleep 2; done'
      
      - name: Run E2E tests
        run: |
          cd apps/web
          npx playwright test
      
      - name: Upload test results
        if: always()
        uses: actions/upload-artifact@v3
        with:
          name: playwright-report
          path: apps/web/playwright-report/
```

## 11. TEST AUTOMATION

### 11.1 Pre-Commit Hooks (Husky)

```json
// package.json
{
  "scripts": {
    "test": "vitest run",
    "test:unit": "vitest run --filter=unit",
    "lint": "eslint . --ext .ts,.tsx",
    "format": "prettier --write ."
  },
  "lint-staged": {
    "*.{ts,tsx}": [
      "eslint --fix",
      "prettier --write",
      "vitest related --run"
    ]
  },
  "husky": {
    "hooks": {
      "pre-commit": "lint-staged",
      "pre-push": "npm test"
    }
  }
}
```

### 11.2 Test Reporting

**JUnit XML Report**:
```bash
# Go
go test ./... -v 2>&1 | go-junit-report > report.xml

# Vitest
vitest run --reporter=junit --outputFile=report.xml
```

**HTML Coverage Report**:
```bash
# Go
go test ./... -coverprofile=coverage.out
go tool cover -html=coverage.out -o coverage.html

# Vitest
vitest run --coverage
# Opens coverage/index.html
```

## 12. QUALITY GATES

### 12.1 Merge Requirements

**Before PR can be merged**:
- [ ] All tests pass (unit, integration, E2E)
- [ ] Coverage ≥ 80% for new/modified files
- [ ] No linter errors (warnings ≤ 5)
- [ ] No security vulnerabilities (high/critical)
- [ ] Performance benchmarks pass (no regression > 10%)
- [ ] Code review approved (≥ 2 reviewers)
- [ ] Documentation updated

### 12.2 Release Quality Gates

**Before release to production**:
- [ ] All tests pass (including load tests)
- [ ] Coverage ≥ 80% (overall)
- [ ] Zero known high/critical security vulnerabilities
- [ ] Performance targets met (p95 < 100ms)
- [ ] Load test passed (5000 concurrent users)
- [ ] E2E tests passed (all critical flows)
- [ ] Security scan passed (OWASP ZAP)
- [ ] Smoke tests passed in staging

## ✅ CHECKLIST DE VALIDATION

### Test Coverage
- [ ] Unit tests ≥ 80% line coverage
- [ ] Integration tests cover all API endpoints
- [ ] E2E tests cover all critical user flows
- [ ] Performance tests for all API endpoints
- [ ] Security tests (SAST + DAST)

### Test Quality
- [ ] Tests are fast (unit < 2min, integration < 5min, E2E < 10min)
- [ ] Tests are deterministic (no flaky tests)
- [ ] Tests are isolated (no shared state)
- [ ] Tests are readable (clear AAA structure)
- [ ] Tests are maintainable (DRY, good naming)

### CI/CD Integration
- [ ] Tests run on every commit
- [ ] Coverage reported to Codecov
- [ ] Quality gates enforced
- [ ] Test results visible in PR
- [ ] Failed tests block merge

### Documentation
- [ ] Testing strategy documented
- [ ] Test fixtures documented
- [ ] CI/CD pipeline documented
- [ ] Quality gates documented

## 📊 MÉTRIQUES DE SUCCÈS

### Coverage Metrics
- **Unit Test Coverage**: ≥ 80%
- **Integration Test Coverage**: ≥ 70%
- **E2E Test Coverage**: ≥ 50% (critical flows 100%)

### Performance Metrics
- **Unit Tests**: < 2 minutes
- **Integration Tests**: < 5 minutes
- **E2E Tests**: < 10 minutes (smoke), < 30 minutes (full suite)
- **Load Tests**: < 15 minutes

### Quality Metrics
- **Test Flakiness**: < 1%
- **Bug Escape Rate**: < 0.1% (bugs found in production)
- **Test Maintenance Time**: < 10% of development time

### CI/CD Metrics
- **Build Success Rate**: > 95%
- **Test Execution Time**: < 10 minutes (average)
- **Deployment Frequency**: Multiple per day
- **Mean Time to Recovery (MTTR)**: < 1 hour

## 🔄 HISTORIQUE DES VERSIONS

| Version | Date | Changements |
|---------|------|-------------|
| 1.0.0 | 2025-11-02 | Version initiale - Stratégie de testing complète |

---

## ⚠️ AVERTISSEMENT

**CETTE STRATÉGIE EST IMMUABLE**

La stratégie de testing définie ici est **VERROUILLÉE**. Toute modification nécessite:

1. **Testing Review Board** (QA Lead, Tech Leads, CTO)
2. **Impact Analysis** (CI/CD, coverage, quality gates)
3. **Team Consensus** (vote à majorité 75%)
4. **Migration Plan** (update tests, CI/CD, docs)

**Seules exceptions autorisées**:
- Nouvelles méthodologies de testing (amélioration)
- Outils de testing plus performants
- Nouvelles exigences de compliance

**Modifications interdites**:
- Réduction coverage minimum (< 80%)
- Suppression quality gates
- Désactivation tests en CI/CD
- Tolérance flaky tests

**"Tests are the safety net that allows rapid development."**

---

**Document créé par**: QA Team + Tech Leads  
**Date de création**: 2025-11-02  
**Prochaine révision**: Quarterly (2026-02-01)  
**Propriétaire**: QA Lead

**Statut**: ✅ **APPROUVÉ ET VERROUILLÉ**