Spring Boot Testing Cheatsheet

cheatsheet_spring_boot_testing.md

Spring Boot Testing Cheatsheet

• [Übersicht über Test-Ansätzen für Spring Controller] https://thepracticaldeveloper.com/2017/07/30/guide-spring-boot-controller-tests/
• [Live-Coding zu MVC-Tests (Februar)] https://www.youtube.com/watch?v=TGcE7lEqhN4&list=PLVBvhDBS_eGWm3_N3sx95lGhBWkxuv_Qn&index=17&t=3513s
• [Testing OAuth] https://www.baeldung.com/oauth-api-testing-with-spring-mvc

Unit tests vs integration tests

Unit tests: MockMVC (standalone)

@RunWith(MockitoJUnitRunner.class)
public class SuperHeroControllerMockMvcStandaloneTest {

    private MockMvc mvc;

    @Mock
    private SuperHeroRepository superHeroRepository;

    @InjectMocks
    private SuperHeroController superHeroController;

    // This object will be magically initialized by the initFields method below.
    private JacksonTester<SuperHero> jsonSuperHero;

    @Before
    public void setup() {
        // We would need this line if we would not use MockitoJUnitRunner
        // MockitoAnnotations.initMocks(this);
        // Initializes the JacksonTester
        JacksonTester.initFields(this, new ObjectMapper());
        // MockMvc standalone approach
        mvc = MockMvcBuilders.standaloneSetup(superHeroController)
                .setControllerAdvice(new SuperHeroExceptionHandler())
                .addFilters(new SuperHeroFilter())
                .build();
    }

    @Test
    public void canRetrieveByIdWhenExists() throws Exception {
        // given
        given(superHeroRepository.getSuperHero(2))
                .willReturn(new SuperHero("Rob", "Mannon", "RobotMan"));

        // when
        MockHttpServletResponse response = mvc.perform(
                get("/superheroes/2")
                        .accept(MediaType.APPLICATION_JSON))
                .andReturn().getResponse();

        // then
        assertThat(response.getStatus()).isEqualTo(HttpStatus.OK.value());
        assertThat(response.getContentAsString()).isEqualTo(
                jsonSuperHero.write(new SuperHero("Rob", "Mannon", "RobotMan")).getJson()
        );
    }