# Nội dung chi tiết ## 1. Nguyên tắc Unit Test API Mỗi API cần test các nhóm case cơ bản: 1. Validate input 2. Auth / permission 3. Business logic 4. Repository interaction 5. Exception handling 6. Logging 7. HTTP status & response --- # 2. Ví dụ API mẫu Controller:
`@RestController@RequestMapping("/users")@RequiredArgsConstructorpublic class UserController { private final UserService userService; @PostMapping public ResponseEntity create( @Valid @RequestBody CreateUserRequest req) { return ResponseEntity.ok(userService.create(req)); }}`
DTO:
`@Datapublic class CreateUserRequest { @NotBlank private String username; @Email private String email;}`
Service:
`@Service@RequiredArgsConstructorpublic class UserService { private final UserRepository repo; public UserResponse create(CreateUserRequest req) { User u = new User(req.getUsername(), req.getEmail()); repo.save(u); return new UserResponse(u.getId(), u.getUsername()); }}`
--- # 3. Cấu trúc test chuẩn Dependency:
`<dependency> <groupId>org.springframework.bootgroupId> <artifactId>spring-boot-starter-testartifactId> <scope>testscope>dependency>`
Controller test dùng: - @WebMvcTest - MockMvc - @MockBean --- # 4. Test Validate Input Case cần có: - thiếu field bắt buộc - email sai format - request null
`@WebMvcTest(UserController.class)class UserControllerValidationTest { @Autowired private MockMvc mockMvc; @MockBean private UserService userService; @Test void create_shouldFail_whenUsernameBlank() throws Exception { String json = """ {"username":"","email":"a@test.com"} """; mockMvc.perform(post("/users") .contentType(MediaType.APPLICATION_JSON) .content(json)) .andExpect(status().isBadRequest()); } @Test void create_shouldFail_whenEmailInvalid() throws Exception { String json = """ {"username":"john","email":"invalid"} """; mockMvc.perform(post("/users") .contentType(MediaType.APPLICATION_JSON) .content(json)) .andExpect(status().isBadRequest()); }}`
--- # 5. Test Auth / Permission Giả sử API cần login:
`@WithMockUser@Testvoid create_shouldSuccess_whenAuthenticated() throws Exception { when(userService.create(any())) .thenReturn(new UserResponse(1L,"john")); String json = """ {"username":"john","email":"a@test.com"} """; mockMvc.perform(post("/users") .contentType(MediaType.APPLICATION_JSON) .content(json)) .andExpect(status().isOk());}`
Test chưa login:
`@Testvoid create_shouldUnauthorized_whenNoAuth() throws Exception { String json = """ {"username":"john","email":"a@test.com"} """; mockMvc.perform(post("/users") .contentType(MediaType.APPLICATION_JSON) .content(json)) .andExpect(status().isUnauthorized());}`
--- # 6. Test Business Logic (Service)
`@ExtendWith(MockitoExtension.class)class UserServiceTest { @Mock private UserRepository repo; @InjectMocks private UserService service; @Test void create_shouldSaveUser() { CreateUserRequest req = new CreateUserRequest(); req.setUsername("john"); req.setEmail("a@test.com"); when(repo.save(any())).thenAnswer(i -> i.getArgument(0)); UserResponse res = service.create(req); assertEquals("john", res.getUsername()); verify(repo).save(any()); }}`
--- # 7. Test Exception Handling Giả sử email trùng:
`when(repo.save(any())) .thenThrow(new DataIntegrityViolationException("dup"));`
Test:
`@Testvoid create_shouldThrow_whenDuplicateEmail() { CreateUserRequest req = new CreateUserRequest(); req.setUsername("john"); req.setEmail("a@test.com"); when(repo.save(any())) .thenThrow(new RuntimeException("duplicate")); assertThrows(RuntimeException.class, () -> service.create(req));}`
--- # 8. Test Logging Giả sử service có log:
`log.info("Create user {}", req.getUsername());`
Test log:
`@ExtendWith(MockitoExtension.class)class UserServiceLogTest { @Mock private UserRepository repo; @InjectMocks private UserService service; @Test void create_shouldLog() { CreateUserRequest req = new CreateUserRequest(); req.setUsername("john"); req.setEmail("a@test.com"); when(repo.save(any())).thenAnswer(i -> i.getArgument(0)); service.create(req); verify(repo).save(any()); }}`
(Thực tế có thể dùng LogCaptor) --- # 9. Test HTTP Response
`@Test@WithMockUservoid create_shouldReturnBody() throws Exception { when(userService.create(any())) .thenReturn(new UserResponse(1L,"john")); String json = """ {"username":"john","email":"a@test.com"} """; mockMvc.perform(post("/users") .contentType(MediaType.APPLICATION_JSON) .content(json)) .andExpect(status().isOk()) .andExpect(jsonPath("$.username").value("john"));}`
--- # 10. Danh sách Case chuẩn cho mỗi API Mỗi API cần tối thiểu: ### Validate - [ ] [ ] thiếu field - [ ] [ ] format sai - [ ] [ ] null body ### Auth - [ ] [ ] chưa login - [ ] [ ] sai role - [ ] [ ] đúng role ### Business - [ ] [ ] flow thành công - [ ] [ ] dữ liệu biên - [ ] [ ] điều kiện đặc biệt ### Repository - [ ] [ ] save OK - [ ] [ ] not found - [ ] [ ] duplicate ### Exception - [ ] [ ] DB lỗi - [ ] [ ] logic lỗi - [ ] [ ] external lỗi ### Response - [ ] [ ] status code - [ ] [ ] body - [ ] [ ] schema ### Log - [ ] [ ] log khi success - [ ] [ ] log khi error --- # 11. Checklist Unit Test API - [ ] [ ] Test validate - [ ] [ ] Test auth - [ ] [ ] Test service - [ ] [ ] Mock repo - [ ] [ ] Test exception - [ ] [ ] Test response - [ ] [ ] Verify interaction - [ ] [ ] No DB thật - [ ] [ ] No network