# Test Summary - cloud-server Project

## Overview
Automated test suite successfully added to the cloud-server project using Vitest.

## Test Files Created

### 1. vitest.config.ts
Configuration file for Vitest with:
- Node environment setup
- Test file pattern matching (`src/**/*.test.ts`)
- Coverage configuration with v8 provider
- Exclusions for test files and type definitions

### 2. src/services/recommendation.test.ts (14 tests)
Tests for RecommendationService class covering:
- **Stack validation**: Invalid stack component rejection
- **Resource calculation**: Memory and vCPU requirements based on stack and scale
- **Scoring algorithm**: 
  - Optimal memory fit (40 points)
  - vCPU fit (30 points)
  - Price efficiency (20 points)
  - Storage bonus (10 points)
- **Budget filtering**: Instance filtering by maximum monthly budget
- **Price extraction**: Monthly price from multiple sources (column, metadata, hourly calculation)
- **Database integration**: Query structure and error handling

### 3. src/middleware/auth.test.ts (21 tests)
Tests for authentication middleware covering:
- **API key validation**: Valid and invalid key verification
- **Constant-time comparison**: Timing attack prevention
- **Missing credentials**: Handling missing API keys and environment variables
- **Length validation**: Key length mismatch detection
- **Special characters**: API key with special characters
- **Synchronous verification**: verifyApiKey function without async operations
- **Unauthorized responses**: 401 response creation with proper headers
- **Security considerations**: Timing variance testing, empty string handling

### 4. src/middleware/rateLimit.test.ts (22 tests)
Tests for rate limiting middleware covering:
- **Request counting**: New window creation and increment tracking
- **Rate limit enforcement**: Blocking requests over limit
- **Window management**: Expiration and reset logic
- **Path-specific limits**: Different limits for `/instances` (100/min) and `/sync` (10/min)
- **IP isolation**: Independent tracking for different client IPs
- **Fail-open behavior**: Graceful handling of KV errors
- **Client IP extraction**: CF-Connecting-IP and X-Forwarded-For fallback
- **Invalid data handling**: Graceful parsing of malformed JSON
- **Rate limit status**: Remaining quota and reset time calculation
- **Response creation**: 429 responses with Retry-After headers

### 5. src/utils/logger.test.ts (37 tests)
Tests for Logger utility covering:
- **Log level filtering**: DEBUG, INFO, WARN, ERROR, NONE levels
- **Environment configuration**: LOG_LEVEL environment variable parsing
- **Structured formatting**: ISO 8601 timestamps, log levels, context
- **Sensitive data masking**: 
  - Top-level key masking (api_key, api_token, password, secret, token, key)
  - Case-insensitive matching
  - Non-sensitive field preservation
- **Factory function**: createLogger with context and environment
- **Data logging**: JSON formatting, nested objects, arrays, null handling
- **Edge cases**: Empty messages, special characters, very long messages

## Test Results

```
Test Files: 4 passed (4)
Tests: 94 passed (94)
Duration: ~700ms
```

### Test Coverage by Module

| Module | File | Tests | Coverage |
|--------|------|-------|----------|
| Services | recommendation.ts | 14 | Scoring algorithm, validation, database queries |
| Middleware | auth.ts | 21 | Authentication, constant-time comparison, security |
| Middleware | rateLimit.ts | 22 | Rate limiting, KV integration, fail-open |
| Utils | logger.ts | 37 | Log levels, formatting, masking |

## Running Tests

### Run all tests
```bash
npm test
```

### Run tests with coverage report
```bash
npm run test:coverage
```

### Run tests in watch mode
```bash
npm test -- --watch
```

### Run specific test file
```bash
npm test -- src/services/recommendation.test.ts
```

## Mock Strategy

All external dependencies are mocked:
- **D1Database**: Mocked with vi.fn() for database operations
- **KVNamespace**: Mocked with in-memory Map for rate limiting
- **Env**: Typed mock objects with required environment variables
- **Console**: Mocked for logger testing to verify output

## Key Testing Patterns

1. **Arrange-Act-Assert**: Clear test structure for readability
2. **Mock isolation**: Each test has isolated mocks via beforeEach
3. **Edge case coverage**: Empty values, special characters, error conditions
4. **Security testing**: Timing attacks, constant-time comparison
5. **Integration validation**: Database queries, KV operations, API responses
6. **Fail-safe testing**: Error handling and graceful degradation

## Notes

- Cache service tests are documented in `src/services/cache.manual-test.md` (requires Cloudflare Workers runtime)
- Tests use Vitest's vi.fn() for mocking (compatible with Jest API)
- D1 and KV operations are mocked since they require Cloudflare Workers environment
- Logger output is captured and validated for proper formatting and masking
- All tests pass with 0 errors and comprehensive coverage of critical paths

## Next Steps

1. **Coverage reports**: Run `npm run test:coverage` to see detailed coverage metrics
2. **E2E tests**: Consider adding Playwright tests for full API workflows
3. **Performance tests**: Add benchmarks for recommendation scoring algorithm
4. **Integration tests**: Test with real D1 database using Miniflare
5. **CI/CD integration**: Add test runs to deployment pipeline