Products Search & Suggestions API Tests

Overview

Comprehensive test coverage for the products search and suggestions API endpoints, including search functionality, query validation, caching, rate limiting, and error handling.

Created: November 28, 2025 Status: COMPLETED Coverage: 96.77% (Combined)

API Endpoints Tested

1. `/api/products/search` - Main Search Route

File: src/app/api/products/search/route.ts Test File: src/app/api/products/search/__tests__/route.test.ts Coverage: 100% Statements, 95.83% Branches, 100% Functions, 100% Lines

2. `/api/products/search/suggestions` - Search Suggestions

File: src/app/api/products/search/suggestions/route.ts Test File: src/app/api/products/search/suggestions/__tests__/route.test.ts Coverage: 100% Statements, 100% Branches, 100% Functions, 100% Lines

Test Coverage Summary

Combined Results

--------------------|---------|----------|---------|---------|-------------------
File                | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s
--------------------|---------|----------|---------|---------|-------------------
All files           |     100 |    96.77 |     100 |     100 |
 search             |     100 |    95.83 |     100 |     100 |
  route.ts          |     100 |    95.83 |     100 |     100 | 40
 search/suggestions |     100 |      100 |     100 |     100 |
  route.ts          |     100 |      100 |     100 |     100 |
--------------------|---------|----------|---------|---------|-------------------

Test Suites: 2 passed, 2 total
Tests:       45 passed, 45 total
Snapshots:   0 total

Test Categories

Main Search Route (`/api/products/search`)

1. Query Validation (3 tests)

✅ Returns empty results when query is missing
✅ Returns empty results when query is too short (1 character)
✅ Accepts query with exactly 2 characters (minimum length)

2. Successful Search (7 tests)

✅ Returns products matching title
✅ Returns products matching description
✅ Returns products matching category
✅ Limits results to 10 items
✅ Sorts results by title ascending
✅ Handles case-insensitive search
✅ Trims whitespace from query

3. Result Transformation (7 tests)

✅ Includes all required fields in results
✅ Calculates average rating correctly
✅ Handles products with no reviews
✅ Uses thumbnailUrl when available
✅ Falls back to url when thumbnailUrl is not available
✅ Sets thumbnail to null when no images exist
✅ Handles null descriptions properly

4. Caching (3 tests)

✅ Uses cache key based on normalized query
✅ Normalizes query for cache (lowercase and trimmed)
✅ Returns cached results when available

5. Rate Limiting (3 tests)

✅ Returns 429 when rate limit exceeded (100 requests)
✅ Includes rate limit headers in 429 response
✅ Rate limits per IP address

6. Performance Tracking (2 tests)

✅ Measures API performance on success
✅ Measures API performance on error

7. Empty Results (2 tests)

✅ Returns empty array when no products match
✅ Returns empty array for special characters query

8. Error Handling (3 tests)

✅ Returns 500 on database error
✅ Returns 500 on cache error
✅ Handles malformed product data gracefully

9. Security Headers (2 tests)

✅ Adds security headers to successful response
✅ Adds security headers to error response

10. Query Parameter Edge Cases (3 tests)

✅ Handles URL-encoded query parameters
✅ Handles query with numbers
✅ Handles very long query strings

11. Multiple Products Scenarios (3 tests)

✅ Handles products with different image configurations
✅ Handles products with varying review counts
✅ Respects the 10 result limit when more products exist

Total Tests: 37

Suggestions Route (`/api/products/search/suggestions`)

1. Query Validation (2 tests)

✅ Returns empty array when query is missing
✅ Returns empty array when query is too short

2. Successful Search (4 tests)

✅ Returns suggestions for valid query
✅ Respects custom limit parameter
✅ Uses default limit of 10
✅ Handles exact 2-character query

3. Empty Results (1 test)

✅ Returns empty array when no suggestions found

4. Error Handling (1 test)

✅ Returns 500 on service error

Total Tests: 8

Mock Strategy

Mocked Dependencies

Main Search Route

@/lib/prisma - Database client
@/lib/security-headers - Security headers
@/lib/logger - Error logging
@/lib/performance - Performance tracking
@/lib/cache - Caching layer
@/lib/http-cache - HTTP cache headers

Suggestions Route

@/lib/search - Search utilities (getSearchSuggestions)
@/lib/security-headers - Security headers
@/lib/logger - Error logging

Mock Data Structure

{
  id: 1,
  title: "iPhone 15",
  description: "Latest iPhone model",
  price: 999,
  discountedPrice: 899,
  images: [
    {
      url: "/images/iphone15.jpg",
      thumbnailUrl: "/images/iphone15-thumb.jpg",
    }
  ],
  category: {
    id: 1,
    title: "Electronics",
  },
  reviews: [{ rating: 5 }, { rating: 4 }]
}

Key Features Tested

1. Search Functionality

Multi-field search (title, description, category)
Query normalization (lowercase, trimmed)
Minimum query length enforcement (2 characters)
Result limiting (10 items max)
Alphabetical sorting

2. Data Transformation

Average rating calculation
Review count aggregation
Image fallback logic (thumbnail → url → null)
Category data inclusion

3. Performance Optimization

Redis caching with normalized keys
Cache TTL management
Performance measurement tracking
HTTP cache headers

4. Security & Rate Limiting

Per-IP rate limiting (100 requests per window)
Security headers on all responses
Rate limit headers in 429 responses
Error information sanitization

5. Error Handling

Database error recovery
Cache error handling
Malformed data detection
Graceful degradation

Test Utilities Used

From `@/test-utils/api-test-helpers`

createMockRequest() - Create mock Next.js requests
parseJsonResponse() - Parse JSON responses
Rate limit clearing utilities

From `@/lib/rate-limit`

clearRateLimit() - Reset rate limits between tests

Edge Cases Covered

Query Validation
- Empty queries
- Single character queries
- Very long queries (1000+ chars)
- Special characters
- URL-encoded parameters
- Numeric queries
- Whitespace handling
Product Data Variations
- Products with thumbnails
- Products without thumbnails (fallback to url)
- Products without images
- Products with no reviews
- Products with varying review counts
- Null descriptions
Error Scenarios
- Database connection failures
- Cache errors
- Malformed product data
- Service errors
Rate Limiting
- Exceeding request limit
- Per-IP isolation
- Rate limit header inclusion

Performance Considerations

Optimizations Tested

✅ Caching with normalized keys
✅ Result limiting (10 items)
✅ Efficient Prisma queries
✅ Performance measurement
✅ HTTP cache headers

Metrics Tracked

API response time
Cache hit/miss rates
Rate limit consumption
Error rates

Coverage Analysis

Lines Not Covered

Line 40 in route.ts: Retry-After header conditional (only set in specific rate limit scenarios)

Why 95.83% Branch Coverage?

The uncovered branch is a defensive check for the Retry-After header that only triggers in specific rate limit timing scenarios that are difficult to test deterministically.

Integration Points

Services Used

Prisma - Database queries
Redis Cache - Result caching
Rate Limiter - Request throttling
Logger - Error tracking
Performance Monitor - Metrics collection
Security Headers - Response hardening

getSearchSuggestions() in @/lib/search
Search term tracking (analytics)
Cache key generation
Result normalization

Running the Tests

Individual Tests

# Main search route
npm test -- src/app/api/products/search/__tests__/route.test.ts --coverage

# Suggestions route
npm test -- src/app/api/products/search/suggestions/__tests__/route.test.ts --coverage

Combined Coverage

npm test -- "src/app/api/products/search" --coverage \
  --collectCoverageFrom="src/app/api/products/search/**/*.ts" \
  --collectCoverageFrom="!src/app/api/products/search/**/*.test.ts"

Future Enhancements

Potential Additional Tests

Integration Tests
- Test with real database (test environment)
- Test cache integration with Redis
- Test rate limiting across multiple requests
Performance Tests
- Load testing for search endpoint
- Cache effectiveness measurement
- Query optimization validation
E2E Tests
- User search flow
- Search suggestions workflow
- Search result interactions
Additional Edge Cases
- Unicode and special character handling
- SQL injection prevention
- XSS prevention in search queries
- Concurrent request handling

PLAN_29_TESTING_COVERAGE.md
API Documentation
Performance Optimization

Conclusion

The products search and suggestions API tests provide comprehensive coverage of:

✅ All major code paths
✅ Error handling scenarios
✅ Security features
✅ Performance optimizations
✅ Edge cases and validation

With 96.77% combined coverage and 45 passing tests, these endpoints are well-tested and production-ready.

Last Updated: November 28, 2025 Maintained By: Development Team (Philip Rehberger)