Overriding beans in Integration tests

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Overriding beans in Integration tests

  1. Overriding beans in Integration tests

    To keep context in cache do not use @DirtiesContext, but use @ContextConfiguration(name = "contextWithFakeBean") and it will create separate context, while it will keep default context in cache. Spring will keep both (or how many contexts you have) in cache.

  2. Overriding beans in Integration tests

    To keep context in cache do not use @DirtiesContext, but use @ContextConfiguration(name = "contextWithFakeBean") and it will create separate context, while it will keep default context in cache. Spring will keep both (or how many contexts you have) in cache.

Solution 1

Since Spring Boot 1.4.x there is an option to use @MockBean annotation to fake Spring beans.

Reaction on comment:

To keep context in cache do not use @DirtiesContext, but use @ContextConfiguration(name = "contextWithFakeBean") and it will create separate context, while it will keep default context in cache. Spring will keep both (or how many contexts you have) in cache.

Our build is this way, where most of the tests are using default non-poluted config, but we have 4-5 tests that are faking beans. Default context is nicely reused

Original Author luboskrnac Of This Content

Solution 2

1.
You can use @Primary annotation:

@Configuration
public class MockRestTemplateConfiguration {

    @Bean
    @Primary
    public RestTemplate restTemplate() {
        return Mockito.mock(RestTemplate.class)
    }
}

BTW, I wrote blog post about faking Spring bean

2.
But I would suggest to take a look at Spring RestTemplate testing support. This would be simple example:

  private MockRestServiceServer mockServer;

  @Autowired
  private RestTemplate restTemplate;

  @Autowired
  private UsersClient usersClient;

  @BeforeMethod
  public void init() {
    mockServer = MockRestServiceServer.createServer(restTemplate);
  }

  @Test
  public void testSingleGet() throws Exception {
    // GIVEN
    int testingIdentifier = 0;
    mockServer.expect(requestTo(USERS_URL + "/" + testingIdentifier))
      .andExpect(method(HttpMethod.GET))
      .andRespond(withSuccess(TEST_RECORD0, MediaType.APPLICATION_JSON));


    // WHEN
    User user = usersClient.getUser(testingIdentifier);

    // THEN
    mockServer.verify();
    assertEquals(user.getName(), USER0_NAME);
    assertEquals(user.getEmail(), USER0_EMAIL);
  }

More examples can be found in my Github repo here

Original Author luboskrnac Of This Content

Solution 3

With @Primary annotation, Bean overriding works with Spring Boot 1.5.X but fails with Spring Boot 2.1.X it throw error:

Invalid bean definition with name 'testBean' defined in sample..ConfigTest$SpringConfig:.. 
There is already .. defined in class path resource [TestConfig.class]] bound

Please add below properties= which will instruct Spring explicitly to allow overriding, it is self explainatory.

@SpringBootTest(properties = ["spring.main.allow-bean-definition-overriding=true"])

UPDATE: You can add the same property in application-test.yml (file name depend upon what test profile name you are tests with)

Original Author ynerdy Of This Content

Solution 4

The Problem in your configuration is that you are using @Configuration for your test configuration. This will replace your main configuration. Instead use @TestConfiguration which will append (override) your main configuration.

46.3.2 Detecting Test Configuration

If you want to customize the primary configuration, you can use a
nested @TestConfiguration class. Unlike a nested @Configuration class,
which would be used instead of your application’s primary
configuration, a nested @TestConfiguration class is used in addition
to your application’s primary configuration.

Example using SpringBoot:

Main class

@SpringBootApplication() // Will scan for @Components and @Configs in package tree
public class Main{
}

Main config

@Configuration
public void AppConfig() { 
    // Define any beans
}

Test config

@TestConfiguration
public void AppTestConfig(){
    // override beans for testing
} 

Test class

@RunWith(SpringRunner.class)
@Import(AppTestConfig.class)
@SpringBootTest
public void AppTest() {
    // use @MockBean if you like
}

Note: Be aware, that all Beans will be created, even those that you override. Use @Profile if you wish not to instantiate a @Configuration.

Original Author Torsten Of This Content

Conclusion

So This is all About This Tutorial. Hope This Tutorial Helped You. Thank You.

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Siddharth

I am an Information Technology Engineer. I have Completed my MCA And I have 4 Year Plus Experience, I am a web developer with knowledge of multiple back-end platforms Like PHP, Node.js, Python and frontend JavaScript frameworks Like Angular, React, and Vue.

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