How to use should_fail method of org.mockitousage.junitrule.VerificationCollectorImplTest class

Here is what I did to test my code using Mockito and Apache HttpBuilder:

Class under test:

import java.io.BufferedReader;
import java.io.IOException;

import javax.ws.rs.core.Response.Status;

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClientBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class StatusApiClient {
private static final Logger LOG = LoggerFactory.getLogger(StatusApiClient.class);

    private String targetUrl = "";
    private HttpClient client = null;
    HttpGet httpGet = null;

    public StatusApiClient(HttpClient client, HttpGet httpGet) {
        this.client = client;
        this.httpGet = httpGet;
    }

    public StatusApiClient(String targetUrl) {
        this.targetUrl = targetUrl;
        this.client = HttpClientBuilder.create().build();
        this.httpGet = new HttpGet(targetUrl);
    }

    public boolean getStatus() {
        BufferedReader rd = null;
        boolean status = false;
        try{
            LOG.debug("Requesting status: " + targetUrl);


            HttpResponse response = client.execute(httpGet);

            if(response.getStatusLine().getStatusCode() == Status.OK.getStatusCode()) {
                LOG.debug("Is online.");
                status = true;
            }

        } catch(Exception e) {
            LOG.error("Error getting the status", e);
        } finally {
            if (rd != null) {
                try{
                    rd.close();
                } catch (IOException ioe) {
                    LOG.error("Error while closing the Buffered Reader used for reading the status", ioe);
                }
            }   
        }

        return status;
    }
}

Test:

import java.io.IOException;

import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.conn.HttpHostConnectException;
import org.junit.Assert;
import org.junit.Test;
import org.mockito.Mockito;

public class StatusApiClientTest extends Mockito {

    @Test
    public void should_return_true_if_the_status_api_works_properly() throws ClientProtocolException, IOException {
        //given:
        HttpClient httpClient = mock(HttpClient.class);
        HttpGet httpGet = mock(HttpGet.class);
        HttpResponse httpResponse = mock(HttpResponse.class);
        StatusLine statusLine = mock(StatusLine.class);

        //and:
        when(statusLine.getStatusCode()).thenReturn(200);
        when(httpResponse.getStatusLine()).thenReturn(statusLine);
        when(httpClient.execute(httpGet)).thenReturn(httpResponse);

        //and:
        StatusApiClient client = new StatusApiClient(httpClient, httpGet);

        //when:
        boolean status = client.getStatus();

        //then:
        Assert.assertTrue(status);
    }

    @Test
    public void should_return_false_if_status_api_do_not_respond() throws ClientProtocolException, IOException {
        //given:
        HttpClient httpClient = mock(HttpClient.class);
        HttpGet httpGet = mock(HttpGet.class);
        HttpResponse httpResponse = mock(HttpResponse.class);
        StatusLine statusLine = mock(StatusLine.class);

        //and:
        when(httpClient.execute(httpGet)).thenThrow(HttpHostConnectException.class);

        //and:
        StatusApiClient client = new StatusApiClient(httpClient, httpGet);

        //when:
        boolean status = client.getStatus();

        //then:
        Assert.assertFalse(status);
    }

}

What do you think folks, do I need to improve something? (Yeah, I know, the comments. That is something I brought from my Spock background :D)

I think you need to pass the Matcher to the jsonPath method. For example.

.andExpect(jsonPath("$.version", is("0.1")))

References:
http://docs.spring.io/spring/docs/3.2.x/javadoc-api/org/springframework/test/web/servlet/result/MockMvcResultMatchers.html#jsonPath(java.lang.String,%20org.hamcrest.Matcher)

https://www.petrikainulainen.net/programming/spring-framework/integration-testing-of-spring-mvc-applications-write-clean-assertions-with-jsonpath/

SpringMVC/ mockMVC/ jsonpath compare list of strings

Further reading has led me to try using ArgumentCaptors and the following works, although much more verbose than I would like.

ArgumentCaptor<String> argument = ArgumentCaptor.forClass(String.class);

verify(errors, atLeastOnce()).add(argument.capture(), any(ActionMessage.class));

List<String> values = argument.getAllValues();

assertTrue(values.contains("exception.message"));
assertTrue(values.contains("exception.detail"));

Why do you need spring to do unit testing? You can only use Mockito to do so without the need to start spring context. This is explained and discussed in details here: https://reflectoring.io/unit-testing-spring-boot/

It's also very confusing for me when it comes to using @MockBean! Is that considered a unit or an integration test? In my opinion, even we're using a mocked bean, but we're still running within spring context and for me this is an integration test (as a unit test doesn't need any spring context to run within). Same site that Brandon mentioned considers @MockBean an integration test https://www.baeldung.com/java-spring-mockito-mock-mockbean.

Image from above site

From Brandon response: "Integration tests should not contain any mocking and both types of testing should be run separately."

What if you want to test an api starting from the controller all the way to DB, but you want to exclude other systems (like kafka or external Microservices)? How would you achieve this? You definitely need @MockBean. This is an integration test even it has mocked beans.

In summary (based on my experience and after searching and reading a lot of contradicting info for days). Here is my opinion:

• I would say, stay away from using spring for unit testing as much as possible and just use Mockito or another framework that doesn’t need spring context. For example, when writing a test for a service class to test some calculation logic, we don’t need spring context and this is a PURE unit test.
• We still can write PURE unit tests for controller classes. We can do that by calling the methods in the controller, then assert that these methods did what is expected (e.g. calling the right underlying methods with correct parameters ..etc). Basically the same way when writing a unit test for a service class. (Maybe these aren’t needed if it’s already gonna be covered in the following types of tests?)
• We still can write pure unit tests for apis without any spring context. This described here. I tried and it worked for me. I'll paste the code at the end of the post.
• When running a test in spring context, this is considered an integration test even if you're using @MockBean. An example of this: if we want to test an api starting from the controller all the way to the DB, but we want to exclude other systems (like kafka, email, or other external Microservices). How would we achieve this? We definitely need @MockBean. This is an integration test even though it uses some mocked beans.

• I think the most confusing part is when testing the api layer only using spring as UserControllerTest in the question does (I mean by that calling the api and making sure it returns the right status code and response format). Is that considered a unit test or an integration test? It is not a unit as unit tests don’t need spring context to run within. It is actually something in between unit and integration tests. This source explains this concept very well https://blog.marcnuri.com/mockmvc-spring-mvc-framework/ (more specifically MockMvc standalone setup) So I think, it goes back then to the team where to place these tests (in the unit test folder, in the integration test folder, in a separate folder?) Also a good naming convention is needed to be used to avoid any confusion with pure unit tests or pure integration tests for the same class. From what I saw, most teams consider those unit tests, but I am not sure if that is the best practice!

  //unit test to call an api using MockMvc and mockito only
  @RunWith(MockitoJUnitRunner.class)
  public class UserControllerTest {
  
  private MockMvc mockMvc;
  @Mock
  UserService userService;
  @InjectMocks
  UserController controllerUnderTest;
  
  @Before
  public void setup() {
      MockitoAnnotations.initMocks(this);
      mockMvc = MockMvcBuilders.standaloneSetup(controllerUnderTest).build();
  }
  
  @Test
  public void testGetUser() throws Exception {
  
      //given:
      when(userService.getUser(.......)).thenReturn(....);
  
      //when:
      String url = "http://localhost:8081/api/ ....your url";
  
      //then:
      this.mockMvc.perform(get(url)).andDo(print()).andExpect(status().isOk());
  }
  

  }

Hope that helps and please let me know if there is any better opinion because I struggled a lot with that :)

You could capture the value, e.g.

final ArgumentCaptor<Double> captor = ArgumentCaptor.forClass(Double.class)
...
verify(myManager).method1(captor.capture());

Then assert:

assertEquals(expected, captor.getValue(), delta)

Or, perhaps, use an argument matcher which does the assertion:

verify(myManager).method1(doubleThat(new ArgumentMatcher<Double>() 
{
    @Override 
    public boolean matches(final Object actual)
    {
        return Math.abs(expected - (Double) actual) <= delta;
    }
}));

Update:

Instead of using either of the methods above, you could use AdditionalMatchers.eq(double, double) instead, e.g.:

verify(myManager).method1(AdditionalMatchers.eq(expected, delta));

Although use AdditonalMatchers matchers wisely, as per the documentation:

AdditionalMatchers provides rarely used matchers, kept only for somewhat compatibility with EasyMock. Use additional matchers very judiciously because they may impact readability of a test. It is recommended to use matchers from Matchers and keep stubbing and verification simple.

So I was actually able to solve my problem. The trick is to manually create your own MockRestServiceServerBuilder to build your MockRestServiceServer instead of using the createServer(RestTemplate) or bindTo(RestTemplate).build() methods, like so:

MockRestServiceServer.MockRestServiceServerBuilder builder = 
    MockRestServiceServer.bindTo(restTemplate);
builder.ignoreExpectOrder(true);
MockRestServiceServer server = builder.build();

By doing so, the underlying RequestExpectationManager field in the MockRestServiceServer is initialized as an UnorderedRequestExpectationManager, allowing you to match requests regardless of the order in which they were made. This solved a lot of headaches for me.

how about you create an anonymous exception of type JsonProcessingException

when(mapper.writeValueAsString(any(Object.class))).thenThrow(new JsonProcessingException("Error"){});

The {} braces does the trick. This is much better since it is not confusing to the reader of the test code.

Take a look at the Mockito API docs. As the linked document mentions (Point # 12) you can use any of the doThrow(),doAnswer(),doNothing(),doReturn() family of methods from Mockito framework to mock void methods.

For example,

Mockito.doThrow(new Exception()).when(instance).methodName();

or if you want to combine it with follow-up behavior,

Mockito.doThrow(new Exception()).doNothing().when(instance).methodName();

Presuming that you are looking at mocking the setter setState(String s) in the class World below is the code uses doAnswer method to mock the setState.

World mockWorld = mock(World.class); 
doAnswer(new Answer<Void>() {
    public Void answer(InvocationOnMock invocation) {
      Object[] args = invocation.getArguments();
      System.out.println("called with arguments: " + Arrays.toString(args));
      return null;
    }
}).when(mockWorld).setState(anyString());

Just incase any M1 Mac users stumble onto this page like I did.

My Issue -

My spring boot project with wiremock tests, would run on my old intel mac but failed to run when I moved to my new M1 Mac.

_ _

I had 2 error messages

• java.lang.IllegalStateException: No Server ALPNProcessors!
• Suppressed: java.lang.UnsatisfiedLinkError: no conscrypt_openjdk_jni-osx-aarch_64

Fix -

I needed a property to test.application

wiremock.server.httpsPort=-1