API Testing
API Test Example
@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
@AutoConfigureMockMvc
class ProductApiTest {
@Test
void shouldGetProductById() throws Exception {
mockMvc.perform(get("/api/products/1"))
.andExpect(status().isOk())
.andExpect(jsonPath("$.name").value("Laptop"))
.andExpect(jsonPath("$.price").value(999.99));
}
@Test
void shouldReturn404WhenProductNotFound() throws Exception {
mockMvc.perform(get("/api/products/999"))
.andExpect(status().isNotFound());
}
}
API Best Practices
Design Principles
- Use nouns, not verbs
- Plural resource names
- Consistent naming conventions
- Proper HTTP status codes
Versioning
- URI versioning (/v1/resource)
- Header versioning
- Deprecation policy
Documentation
- OpenAPI/Swagger specs
- Request/Response examples
- Error code documentation
- Rate limit documentation
Key Points
- Understanding API Testing is essential for production systems
- Always consider scalability and maintainability
- Test thoroughly before deploying to production
- Monitor performance and set up alerting
Common Patterns
- Validation: Always validate input at the boundary
- Error Handling: Use structured error responses
- Logging: Log key events for debugging
- Testing: Unit, integration, and load tests
- Documentation: Keep docs updated with code changes
Practice Problems
0 / 2 solved
API Testing Edge Cases
Identify and handle edge cases for API Testing. What happens under high load, with invalid input, or during failures?
Solution
// Edge case handling:
// 1. Null/empty input -> validation
// 2. High load -> rate limiting, queuing
// 3. Failures -> retries, circuit breaker
// 4. Concurrent access -> locks, idempotency API Testing Testing Strategy
Write a testing strategy for API Testing. Include unit tests, integration tests, and performance tests.
Solution
// Test plan:
// - Unit: 80% coverage target
// - Integration: API contracts
// - Performance: latency, throughput
// - Chaos: failure injection Quiz
1. API testing validates?
2. RANDOM_PORT in tests?
3. What is a common mistake when implementing API Testing?
Flashcards
Question
API testing validates?
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Answer
Status, body, headers
Question
RANDOM_PORT purpose?
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Answer
Avoid port conflicts
Question
API Testing best practices
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Answer
Follow SOLID principles, write clean code, test thoroughly, document decisions, and monitor in production.
Revision Notes
Key Takeaways
- 1. Test status codes, response bodies, headers
- 2. Test happy path and error cases
- 3. Use @SpringBootTest(webEnvironment = RANDOM_PORT)
- 4. Validate JSON with jsonPath
Interview Tips
- • Write API tests
- • Test error cases
Cheat Sheet
API Testing
- Validate: status, body, headers
- Test: happy path + error cases
- RANDOM_PORT: avoid conflicts
- jsonPath: validate JSON fields