Spring Boot - Testing

Frameworks

Spring-boot-starter-test

• Always start with the starter 
• Integrate the above frameworks

<dependency>

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-test</artifactId>

<scope>test</scope>

</dependency>

JUnit

• For unit testing

Hamcrest

• Matching and assertion

Mockito

• Mock objects and verify

Spring Test

• Testing tools & integration testing support

Creating a Test

First in src/test/java create the following class for test the Controller

package com.ericsson.project;

import org.junit.Test;

public class AppTest 

{

   @Test

    public void testApp()

    {

    }

}

• Add the following code in testApp()

HomeController hc = new HomeController();

    String result = hc.home();

    assertEquals(result, "Das boot");

Creating a Mockito Test

Mockito helps to inject dependencies

• Create another test
• Inject the controller

@InjectMocks

private ShipwreckController swc;

• Inject the repository

@Mock

private ShipwreckRepository swr;

• Initialize all the mock objects 

@Before(value = "")

public void nit(){

MockitoAnnotations.initMocks(this);

}

• Create test method

@Test

public void testhipwreckGet(){

Shipwreck sw = new Shipwreck();

sw.setId(1L);

when(swr.findOne(1l)).thenReturn(sw);

Shipwreck sw2 = swc.get(1l);

assertEquals(1l, sw2.getId().longValue());

}

• All Mockito Test

package com.ericsson.project;

import static org.junit.Assert.*;

import static org.mockito.Mockito.*;

import org.junit.Before;

import org.junit.Test;

import org.mockito.InjectMocks;

import org.mockito.Mock;

import org.mockito.MockitoAnnotations;

import com.ericsson.project.controller.ShipwreckController;

import com.ericsson.project.model.Shipwreck;

import com.ericsson.project.repository.ShipwreckRepository;

public class ShimpwreckControllerTest {

@InjectMocks

private ShipwreckController swc;

@Mock

private ShipwreckRepository swr;

@Before

public void nit(){

MockitoAnnotations.initMocks(this);

}

@Test

public void testhipwreckGet(){

Shipwreck sw = new Shipwreck();

sw.setId(1L);

when(swr.findOne(1l)).thenReturn(sw);

Shipwreck sw2 = swc.get(1l);

assertEquals(1l, sw2.getId().longValue());

}

}

• Using Hamcrest

Has another syntax to create the matching

assertThat(sw2.getId(), is(1l));  

Create Integration Test

To convert JUnit test in Integration Test

• Annotate the tests with @RunWith( SpringJUnit4ClassRunner.class )
• Add @SpringApplicationConfiguration( App.class ) 
• Create the test method

package com.ericsson.project;

import java.util.List;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.boot.test.SpringApplicationConfiguration;

import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.ericsson.project.model.Shipwreck;

import com.ericsson.project.repository.ShipwreckRepository;

import static org.hamcrest.MatcherAssert.assertThat;

import static org.hamcrest.Matchers.*;

@RunWith( SpringJUnit4ClassRunner.class )

@SpringApplicationConfiguration( App.class ) 

public class ShipwreckIntegrationTest {

@Autowired

private ShipwreckRepository swr;

@Test

public void Test(){

List<Shipwreck> wrecks = swr.findAll();

assertThat( wrecks.size(), is( greaterThanOrEqualTo(0)));

}

}

Create Web Integration Test

Web Integration Test == calling Rest API 

• Add the annotation  @WebIntegrationTest
• Define the URL

@RunWith( SpringJUnit4ClassRunner.class )
@SpringApplicationConfiguration( App.class )
@org.springframework.boot.test.WebIntegrationTest
public class WebIntegrationTest {

@Test
public void testService() throws IOException{

RestTemplate rt = new TestRestTemplate();
ResponseEntity<String> response = rt.getForEntity("http://localhost:8080/api/v1/shipwrecks", String.class);

assertThat(response.getStatusCode(), equalTo(HttpStatus.OK));

ObjectMapper om = new ObjectMapper();
JsonNode responseJson = om.readTree(response.getBody());

assertThat(responseJson.isMissingNode(), is(false));
assertThat(responseJson.toString(), equalTo("[]"));

}
}