Backend Testing Skill

When to Use

• •Writing unit tests for services or repositories
• •Writing controller tests with MockMvc
• •Writing integration tests
• •Reviewing test coverage or test quality

Stack

• •JUnit5 + Spring Boot Test
• •MockMvc for controller tests
• •(Optional) Testcontainers for integration tests

Mandatory Rules

• •Mocking Annotation: Do NOT use @MockBean. You MUST use @MockitoBean when replacing a bean in the Spring Test Context.
• •Spying Annotation: Do NOT use @SpyBean. Use @MockitoSpyBean instead.
• •Best Practices: Do not recommend or include @MockBean in any test examples, guides, or code reviews within this project.

Minimum Requirements

Each endpoint requires:

• •At least 1 success test
• •At least 1 failure test

Document important endpoints with Spring REST Docs.

What to Test

1. •Validation errors - Invalid input handling
2. •Authorization errors - If applicable
3. •Idempotency behaviors - Duplicate request handling
4. •TTL expiry behaviors - Session/token expiration

Test Organization

src/test/java/
├── controller/
│   └── {Feature}ControllerTest.java
├── service/
│   └── {Feature}ServiceTest.java
└── integration/
    └── {Feature}IntegrationTest.java

Test Naming Convention

@Test
void should_ReturnSuccess_When_ValidInput() { }

@Test
void should_ThrowException_When_InvalidInput() { }