java-testing-lab/spring-test-slices/src/test/java/lab/slices/WebMvcSliceTest.java

package lab.slices;

import static org.assertj.core.api.Assertions.assertThat;
import static org.mockito.BDDMockito.given;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

import java.math.BigDecimal;
import java.time.LocalDate;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.webmvc.test.autoconfigure.WebMvcTest;
import org.springframework.context.ApplicationContext;
import org.springframework.test.context.bean.override.mockito.MockitoBean;
import org.springframework.test.web.servlet.MockMvc;

/** @WebMvcTest: the web layer only. BookService is replaced by a Mockito mock. */
@WebMvcTest(BookController.class)
class WebMvcSliceTest {

    @Autowired
    MockMvc mvc;

    @Autowired
    ApplicationContext ctx;

    @MockitoBean
    BookService service;

    @Test
    void returnsABookAsJson_usingTheJacksonComponentAndTheControllerAdvice() throws Exception {
        given(service.get(1L)).willReturn(
                new Book("9780134685991", "Effective Java", "Joshua Bloch", new BigDecimal("499"), LocalDate.of(2018, 1, 6)));
        given(service.get(99L)).willThrow(new BookNotFoundException(99L));

        String ok = mvc.perform(get("/api/books/1"))
                .andExpect(status().isOk())
                .andExpect(jsonPath("$.title").value("Effective Java"))
                .andExpect(jsonPath("$.price").value("INR 499.00"))
                .andExpect(jsonPath("$.published_on").value("2018-01-06"))
                .andReturn().getResponse().getContentAsString();

        String missing = mvc.perform(get("/api/books/99"))
                .andExpect(status().isNotFound())
                .andExpect(jsonPath("$.title").value("Book not found"))
                .andReturn().getResponse().getContentAsString();

        Transcript t = new Transcript("01-webmvc-slice.txt")
                .line("@WebMvcTest(BookController.class) with @MockitoBean BookService")
                .line("")
                .line("GET /api/books/1   -> 200 %s", ok)
                .line("GET /api/books/99  -> 404 %s", missing)
                .line("")
                .line("beans in this context:");
        BeanProbe.record("WebMvcTest", ctx).forEach(l -> t.line("  %s", l));
        t.write();

        assertThat(ctx.getBeanNamesForType(BookService.class)).as("the mock is the only BookService").hasSize(1);
        assertThat(ctx.getBeanNamesForType(BookRepository.class)).isEmpty();
        assertThat(ctx.getBeanNamesForType(AuditLogger.class)).isEmpty();
    }
}