TestContainers: JEEConf 2017

http://jeeconf.com/program/testcontainers-integration-testing-without-the-hassle/

Transcript

1. TestContainers Integration testing without the hassle Sergei @bsideup Egorov
2. About me • Site Reliability Engineer at • Before: ZeroTurnaround, TransferWise, etc… • TestContainers’ co-maintainer • In love with Docker since 2013 @bsideup
3. Integration testing Why it matters?
6. Verify how your software product will behave in real-world conditions
7. Isolated from other system components to avoid false negatives
8. Real: databases, file systems, network interfaces, …
9. Grey box testing - we know some inner details, but mostly use public APIs
11. Unit testing • Simulation tests are green, yay! • Everything is mocked • DB is written by others, why should I test it?
12. Integration testing https://commons.wikimedia.org/wiki/File:Cd4007.jpg • Jeez, how did it passed the Unit testing? • Is it a smoke? @#$%! YES IT IS! • Who knew that 100w soldering gun was a bit too powerful for it?
13. System testing https://commons.wikimedia.org/wiki/File:UART_8250_Microchip.jpg • Takes a lot of time to solder • “Oh no, the power bus is too far away from my microchip!” • Interference between the components
14. Production
15. Integration testing Real-world, but isolated testing Spot the issues before the real environment Can be run during the development You have to start real databases Should be cross-platform Slower than Unit testing Pros Cons
16. Obvious solution
18. Abstraction layer
19. CI friendly
20. Cross-platform
21. Docker Compose FTW! redis:
 image: redis
 ports:
 - "6379:6379"
 postgres:
 image: postgres
 ports:
 - "5432:5432"
 elasticsearch:
 image: elasticsearch:5.0.0
 ports:
 - "9200:9200"

22. But…
23. No ports randomization redis:
 image: redis
 ports:
 - "6379:6379"
 postgres:
 image: postgres
 ports:
 - "5432:5432"
 elasticsearch:
 image: elasticsearch:5.0.0
 ports:
 - "9200:9200"

24. Fighting with Docker environment
25. There is no place like
26. There is no place like Except Docker Machine
27. Can we improve that?
29. Remove the database
30. Remove the database
32. TestContainers • http://github.com/testcontainers/testcontainers-java • Wraps docker-java library • Docker environment discovery (Win, Mac, Linux) • Will start docker-machine if it’s not started yet • Containers cleanup on JVM shutdown
33. As simple as PostgreSQLContainer postgresql = new PostgreSQLContainer()
 
 GenericContainer redis = new GenericContainer("redis:3")
 .withExposedPorts(6379)
34. Users
35. Use case #1: testing of microservices • REST service • Java, Spring Boot • Redis and PostgreSQL • Calls some other micro-services
36. @RunWith(SpringRunner.class) @SpringBootTest(webEnvironment = RANDOM_PORT) @ContextConfiguration(initializers = Initializer.class) public abstract class AbstractIntegrationTest { @ClassRule public static PostgreSQLContainer postgreSql = new PostgreSQLContainer(); @ClassRule public static GenericContainer redis = new GenericContainer("redis:3.0.6") .withExposedPorts(6379); @ClassRule public static MockServerContainer mockServer = new MockServerContainer(); }
37. @RunWith(SpringRunner.class) @SpringBootTest(webEnvironment = RANDOM_PORT) @ContextConfiguration(initializers = Initializer.class) public abstract class AbstractIntegrationTest { @ClassRule public static PostgreSQLContainer postgreSql = new PostgreSQLContainer(); @ClassRule public static GenericContainer redis = new GenericContainer("redis:3.0.6") .withExposedPorts(6379); @ClassRule public static MockServerContainer mockServer = new MockServerContainer(); } Still using all the Spring goodies!
38. @RunWith(SpringRunner.class) @SpringBootTest(webEnvironment = RANDOM_PORT) @ContextConfiguration(initializers = Initializer.class) public abstract class AbstractIntegrationTest { @ClassRule public static PostgreSQLContainer postgreSql = new PostgreSQLContainer(); @ClassRule public static GenericContainer redis = new GenericContainer("redis:3.0.6") .withExposedPorts(6379); @ClassRule public static MockServerContainer mockServer = new MockServerContainer(); } External dependencies
40. public class MockServerContainer<SELF extends MockServerContainer<SELF>> extends GenericContainer<SELF> { public MockServerContainer() { super("jamesdbloom/mockserver:latest"); addExposedPorts(8080); } private MockServerClient client; @Override protected void containerIsStarted(InspectContainerResponse containerInfo) { super.containerIsStarted(containerInfo); client = new MockServerClient(getContainerIpAddress(), getMappedPort(getExposedPorts().get(0))); } }
41. public class MockServerContainer<SELF extends MockServerContainer<SELF>> extends GenericContainer<SELF> { public MockServerContainer() { super("jamesdbloom/mockserver:latest"); addExposedPorts(8080); } private MockServerClient client; @Override protected void containerIsStarted(InspectContainerResponse containerInfo) { super.containerIsStarted(containerInfo); client = new MockServerClient(getContainerIpAddress(), getMappedPort(getExposedPorts().get(0))); } }
42. Demo
43. Use case #2: Docker as Selenium driver • Selenium/Selenide tests • No need to install Chrome/Firefox/etc • CI friendly
44. @Rule public BrowserWebDriverContainer chrome = new BrowserWebDriverContainer() .withDesiredCapabilities(DesiredCapabilities.chrome()) .withRecordingMode(RECORD_ALL, new File("target"));
45. @Rule public BrowserWebDriverContainer chrome = new BrowserWebDriverContainer() .withDesiredCapabilities(DesiredCapabilities.chrome()) .withRecordingMode(RECORD_ALL, new File("target")); RemoteWebDriver driver = chrome.getWebDriver(); driver.get("https://wikipedia.org"); WebElement searchInput = driver.findElementByName("search"); searchInput.sendKeys("Rick Astley"); searchInput.submit(); WebElement otherPage = driver.findElementByLinkText("Rickrolling"); otherPage.click(); boolean expectedTextFound = driver.findElementsByCssSelector("p") .stream() .anyMatch(element -> element.getText().contains("meme")); assertTrue("The word 'meme' is found on a page about rickrolling", expectedTextFound);
46. @Rule public BrowserWebDriverContainer chrome = new BrowserWebDriverContainer() .withDesiredCapabilities(DesiredCapabilities.chrome()) .withRecordingMode(RECORD_ALL, new File("target")); RemoteWebDriver driver = chrome.getWebDriver(); driver.get("https://wikipedia.org"); WebElement searchInput = driver.findElementByName("search"); searchInput.sendKeys("Rick Astley"); searchInput.submit(); WebElement otherPage = driver.findElementByLinkText("Rickrolling"); otherPage.click(); boolean expectedTextFound = driver.findElementsByCssSelector("p") .stream() .anyMatch(element -> element.getText().contains("meme")); assertTrue("The word 'meme' is found on a page about rickrolling", expectedTextFound); import org.openqa.selenium.remote.RemoteWebDriver;
47. @Rule public BrowserWebDriverContainer chrome = new BrowserWebDriverContainer() .withDesiredCapabilities(DesiredCapabilities.chrome()) .withRecordingMode(RECORD_ALL, new File("target")); RemoteWebDriver driver = chrome.getWebDriver(); driver.get("https://wikipedia.org"); WebElement searchInput = driver.findElementByName("search"); searchInput.sendKeys("Rick Astley"); searchInput.submit(); WebElement otherPage = driver.findElementByLinkText("Rickrolling"); otherPage.click(); boolean expectedTextFound = driver.findElementsByCssSelector("p") .stream() .anyMatch(element -> element.getText().contains("meme")); assertTrue("The word 'meme' is found on a page about rickrolling", expectedTextFound);
48. Demo
49. • http://testcontainers.org • testcontainers/testcontainers-java-examples • Integration testing is a must • Docker works great for testing • Unified env for Dev and CI
50. Questions?
51. @bsideup bsideup
52. https://commons.wikimedia.org/wiki/File:Thats_all_folks.svg