One of the best experiences you might have as a developer is when you are running your continuous delivery pipeline and one of the test failed because it has found a bug. At this point you see that thanks of your tests you are producing a less buggy software. This should be the normal case, in green field projects, but unlikely to happen when running legacy code with a lot of untested code.

1. USING DOCKER FOR TESTING LEGACY
@alexsotob

2. @alexsotob2
Alex Soto
Red Hat Engineer
www.lordofthejars.com
@alexsotob
Who Am I?

3. @alexsotob3
https://www.manning.com/books/testing-java-microservices

4. @alexsotob4
Questions

5. @alexsotob5
ENIAC

6. @alexsotob
Quality for your Customers
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7. @alexsotob
Enable change
Refactor code
Validate functionality
The right thing, and the thing right
Trust deployments
Testing
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8. @alexsoto8
What is Legacy Code?

9. @alexsotob
Old Code Needs To Be Maintained
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Apply Test First Strategies
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How To Start?
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12. @alexsotob
Characterization Tests
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13. @alexsotob
Tests By Division
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15. @alexsotob

16. @alexsotob
Testing Containers
docker build -t myorg/myservice:1.0.0 .
docker run --rm -ti -p 8080:8080 myorg/myservice:1.0.0
docker-compose up
mvn clean test
docker-compose stop
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Docker Run
Docker Compose Run
Run tests
Stop Docker Containers

17. @alexsotob17

18. @alexsotob
Arquillian Cube DSL
@RunWith(SpringRunner.class)
@SpringBootTest(classes = PingPongController.class, webEnvironment = RANDOM_PORT)
@ContextConfiguration(initializers = PingPongSpringBootTest.Initializer.class)
public class PingPongSpringBootTest {
@ClassRule
public static ContainerDslRule redis = new ContainerDslRule("redis:3.2.6")
.withPortBinding(6379);
@Autowired
TestRestTemplate restTemplate;
@Test
public void should_get_data_from_redis() {
}
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Spring Boot Test
Custom Initializer
Container Definition
public static class Initializer implements
ApplicationContextInitializer<ConfigurableApplicationContext> {
@Override
public void initialize(ConfigurableApplicationContext configurableApplicationContext) {
EnvironmentTestUtils.addEnvironment("testcontainers",
configurableApplicationContext.getEnvironment(),
"spring.redis.host=" + redis.getIpAddress(),
"spring.redis.port=" + redis.getBindPort(6379)
);
Sets Container Environment

19. @alexsotob
Arquillian Cube Example
@RunWith(Arquillian.class)
public class HelloWorldTest {
@ArquillianResource
@DockerUrl(containerName = "helloworld", exposedPort = 8080)
RequestSpecBuilder requestSpecBuilder;
@Test
public void should_receive_ok_message() {
RestAssured
.given()
.spec(requestSpecBuilder.build())
.when()
.get()
.then()
.assertThat().body("status", equalTo("OK"));
}
}
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Arquillian Runner
REST-Assured Integration
Environment Resolver
Normal REST-Assured Call
helloworld:
image: jonmorehouse/ping-pong
ports:
- "8080:8080"
src/test/docker/docker-compose.yml

20. @alexsotob
DEMO
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21. @alexsotob21
Persistence Tests

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APE

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APE SQL example
@Rule
public ArquillianPersistenceRule arquillianPersistenceRule =
new ArquillianPersistenceRule();
@DbUnit
@ArquillianResource
RdbmsPopulator rdbmsPopulator;
@Before
public void populateData() {
// Given:
rdbmsPopulator.forUri(jdbcUri).withDriver(Driver.class).withUsername("sa")
.withPassword("").usingDataSet("composers.yml")
.execute();
}
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APE JUnit Rule
(not necessary with
Arquillian Runner)
Set DBUnit usage
Configure Connection and Dataset
Populate
composers:
- id: 1
name: Wolfgang Amadeus Mozart
birthdate: 27/1/1756
died: 5/12/1791

24. @alexsotob
APE SQL example
@After
public void clean_database() {
// Given:
rdbmsPopulator.forUri(jdbcUri).withDriver(Driver.class).withUsername("sa")
.withPassword("").usingDataSet("composers.yml")
.clean();
}
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Clean After Test
Clean Database

25. @alexsotob
Boilerplate Code
Programmatic/Declarative
@UsingDataSet/@ShouldMatchDataSet
SQL Support
DBUnit and Flyway
REST API Support
Postman Collections
NoSQL Support
MongoDB, Couchbase, CouchDB, Vault, Redis, Infinispan
Benefits of Arquillian APE
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26. @alexsotob26
DEMO

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Visual Testing

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Selenium
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Arquillian Drone
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30. @alexsotob
Arquillian Drone example
@RunWith(Arquillian.class)
public class LoginScreenTest {
@Drone
private WebDriver browser;
@Test
public void should_login_user() {
driver.get("www.mypage.com/login");
driver.findElement(By.id("loginForm:login")).click();
}
}
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Arquillian Runner
Injection of WebDriver instance

31. @alexsotob
Arquillian Graphene
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Arquillian Graphene Page Object example
@Location("login.xhtml")
public class HomePage {
@Page
private UserPage userPage;
@FindBy(id = "submit")
private WebElement submitButton;
@FindBy(id = "form")
private LoginPopup loginPopup;
// methods
}
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Location of the page
Another Page Object
Find web element by id
Page fragment

33. @alexsotob
Arquillian Graphene example
@RunWith(Arquillian.class)
public class LoginTest {
@Drone
WebDriver webDriver;
@Test
public void should_create_a_new_speaker(@InitialPage HomePage homePage) {
homePage.login("username", "pasword");
}
}
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Open given page
Use Page Object method

34. @alexsotob34
Docker and Selenium

35. @alexsotob
DEMO
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36. @alexsotob36
Let’s Wind Down

37. @alexsotob37

38. @alexsotob38
Automate Everything

39. @alexsotob39

40. @alexsotob40

41. Thank You
https://github.com/lordofthejars/conference-testbed
https://github.com/lordofthejars/jpa-onetomany-springboot-maven-mysql