GeeCON 2019: Testcontainers: a year-in-review

Unit testing is fine, but without proper integration testing, especially if you work with external resources like databases and other services, you might not know how your application will actually behave once it has been deployed to the real production environment.

Testcontainers is a popular JVM testing library that provides lightweight, throwaway instances of common databases, Selenium web browsers, or anything else that can run in a Docker container.

In this talk, we will briefly go throught the past, present and the future of the library.

Transcript

1. Testcontainers:
 a year-in-review Sergei Egorov Kraków, 15-17 May 2019 @bsideup
2. Top ques!ons (0) Room 11 Join at slido.com #geecon2019 Join at #geecon2019 Room 11 slido com Ask questions at
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 #geecon2019
 room 1
3. Tweet photos
 #geecon
 @bsideup
4. About me • Testcontainers co-maintainer • Staff Engineer at Pivotal’s Spring R&D, working on Project Reactor ⚛ • Berlin Spring User Group co-organizer • Developer tools geek @bsideup
5. Integration testing Why it matters?
6. @bsideup
7. @bsideup
8. 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 @bsideup
9. Integration testing transformation @bsideup
10. Mocking Integration testing transformation @bsideup
11. Mocking Local DBs Integration testing transformation @bsideup
12. Mocking Local DBs VMs
 (Vagrant) Integration testing transformation @bsideup
13. Mocking Local DBs VMs
 (Vagrant) Docker Integration testing transformation @bsideup
14. Mocking Local DBs VMs
 (Vagrant) Docker Fig
 (aka Docker Compose) Integration testing transformation @bsideup
15. Mocking Local DBs VMs
 (Vagrant) Docker Fig
 (aka Docker Compose) Docker API Integration testing transformation @bsideup
17. Abstraction layer
18. CI friendly
19. Cross-platform
20. Docker Compose FTW! redis:
 image: redis
 ports:
 - "6379:6379"
 postgres:
 image: postgres
 ports:
 - "5432:5432"
 elasticsearch:
 image: elasticsearch:5.0.0
 ports:
 - "9200:9200"
 @bsideup
21. But…
22. Declarative YAML redis:
 image: redis
 ports:
 - "6379:6379"
 postgres:
 image: postgres
 ports:
 - "5432:5432"
 elasticsearch:
 image: elasticsearch:5.0.0
 ports:
 - "9200:9200"
 @bsideup
23. ports randomization? redis:
 image: redis
 ports:
 - "6379:6379"
 postgres:
 image: postgres
 ports:
 - "5432:5432"
 elasticsearch:
 image: elasticsearch:5.0.0
 ports:
 - "9200:9200"
 @bsideup
24. Container per test? redis:
 image: redis
 ports:
 - "6379:6379"
 postgres:
 image: postgres
 ports:
 - "5432:5432"
 elasticsearch:
 image: elasticsearch:5.0.0
 ports:
 - "9200:9200"
 @bsideup
25. IDE integration? @bsideup
26. Fighting with Docker environment
27. There is no place like
28. There is no place like … unless there is
29. Can we improve that?
31. Testcontainers • http://github.com/testcontainers/testcontainers-java • Wraps docker-java library • Docker environment discovery (Win, Mac, Linux) • Containers cleanup on JVM shutdown @bsideup
32. As simple as PostgreSQLContainer postgresql = new PostgreSQLContainer()
 
 GenericContainer redis = new GenericContainer("redis:3")
 .withExposedPorts(6379) @bsideup
33. Users
34. @bsideup
35. Demo
36. 1.6.x Jan, 2018 @bsideup
37. 1.6.x • Kafka module Jan, 2018 @bsideup try (KafkaContainer kafka = new KafkaContainer()) { kafka.start(); testKafkaFunctionality(kafka.getBootstrapServers()); }
38. 1.6.x • Kafka module • “Ryuk” Jan, 2018 @bsideup
39. 1.7.x Apr, 2018 @bsideup
40. 1.7.x • Maven BOM Apr, 2018 @bsideup <dependencyManagement> <dependencies> <dependency> <groupId>org.testcontainers</groupId> <artifactId>testcontainers-bom</artifactId> <version>1.11.2</version> <type>bom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement>
41. 1.7.x • Maven BOM • DockerCompose
 wait strategies Apr, 2018 @bsideup new DockerComposeContainer(new File("docker-compose.yml")) .withExposedService( "redis_1", REDIS_PORT, Wait.forListeningPort() ) .withExposedService( "db_1", 3306, Wait.forLogMessage(".*ready for connections.*\\s", 1) );
42. 1.7.x • Maven BOM • DockerCompose
 wait strategies • Daemon threads Apr, 2018 @bsideup kiraThread.setDaemon(true); kiraThread.start();
43. 1.7.x • Maven BOM • DockerCompose
 wait strategies • Daemon threads • MockServer module Apr, 2018 @bsideup try (MockServerContainer mockServer = new MockServerContainer()) { mockServer.start(); String expectedBody = "Hello Default World!"; MockServerClient client = new MockServerClient( mockServer.getContainerIpAddress(), mockServer.getServerPort() ); client.when(request("/hello")).respond(response(expectedBody)); // ... }
44. 1.8.x Jun, 2018 @bsideup
45. 1.8.x • OkHttp transport Jun, 2018 @bsideup
46. 1.8.x • OkHttp transport • Test framework
 agnostic Jun, 2018 @bsideup public interface Startable extends AutoCloseable { void start(); void stop(); } public interface TestLifecycleAware { default void beforeTest(TestDescription description) {} default void afterTest( TestDescription description, Optional<Throwable> throwable ) {} }
47. 1.8.x • OkHttp transport • Test framework
 agnostic • Docker cred. helpers Jun, 2018 @bsideup { "auths": { }, "HttpHeaders": { "User-Agent": "Docker-Client/18.03.0-ce (darwin)" }, "credHelpers": { "registry.example.com": “helper" } }
48. 1.8.x • OkHttp transport • Test framework
 agnostic • Docker cred. helpers • copyFileToContainer Jun, 2018 @bsideup GenericContainer container = new GenericContainer("alpine:latest") // Look, Ma! No volumes mounting! .withCopyFileToContainer( MountableFile.forClasspathResource(“/mappable-resource/"), containerPath )
49. 1.8.x • OkHttp transport • Test framework
 agnostic • Docker cred. helpers • copyFileToContainer • Pulsar module • Couchbase module • Cassandra module Jun, 2018 @bsideup
50. 1.9.x Sep, 2018 @bsideup
51. 1.9.x • OkHttp by default Sep, 2018 @bsideup
52. 1.9.x • OkHttp by default • Windows npipe support Sep, 2018 @bsideup No longer needed
53. 1.9.x • OkHttp by default • Windows npipe support • Registry auth on Windows Sep, 2018 @bsideup
54. 1.9.x • OkHttp by default • Windows npipe support • Registry auth on Windows • Fix local Docker Compose
 on Windows Sep, 2018 @bsideup new DockerComposeContainer(new File("docker-compose.yml")) .withExposedService("redis_1", REDIS_PORT) .withExposedService("db_1", 3306) .withLocalCompose(true);
55. 1.9.x • OkHttp by default • Windows npipe support • Registry auth on Windows • Fix local Docker Compose
 on Windows • Host ports exposing Sep, 2018 @bsideup @BeforeClass public static void setUp() { localPort = server.getAddress().getPort(); Testcontainers.exposeHostPorts(localPort); } @Rule public BrowserWebDriverContainer browser = new BrowserWebDriverContainer() .withCapabilities(new ChromeOptions()); @Test public void testContainerRunningAgainstExposedHostPort() { RemoteWebDriver webDriver = browser.getWebDriver(); webDriver.get( String.format("http://host.testcontainers.internal:%d/", localPort)); final String pageSource = webDriver.getPageSource(); assertTrue(pageSource.contains("Hello from the host!")); }
56. 1.9.x • OkHttp by default • Windows npipe support • Registry auth on Windows • Fix local Docker Compose
 on Windows • Host ports exposing • Random ports in Couchbase Sep, 2018 @bsideup
57. 1.9.x • OkHttp by default • Windows npipe support • Registry auth on Windows • Fix local Docker Compose
 on Windows • Host ports exposing • Random ports in Couchbase Sep, 2018 @bsideup
58. 1.9.x • OkHttp by default • Windows npipe support • Registry auth on Windows • Fix local Docker Compose
 on Windows • Host ports exposing • Random ports in Couchbase • ClickHouse and Postgis modules Sep, 2018 @bsideup
59. 1.10.x Nov, 2018 @bsideup
60. 1.10.x • JUnit 5 support Nov, 2018 @bsideup @Testcontainers class MyTestcontainersTests { // will be shared between test methods @Container static final MySQLContainer MYSQL_CONTAINER = new MySQLContainer(); // will be started before and stopped after each test method @Container PostgreSQLContainer postgresqlContainer = new PostgreSQLContainer() .withDatabaseName("foo") .withUsername("foo") .withPassword(“secret"); @Test void test() { assertTrue(MYSQL_CONTAINER.isRunning()); assertTrue(postgresqlContainer.isRunning()); } }
61. 1.10.x • JUnit 5 support • New docs & more examples Nov, 2018 @bsideup
62. 1.10.x • JUnit 5 support • New docs & more examples • Env var to turn off Ryuk
 (for public CIs) Nov, 2018 @bsideup
63. 1.10.x • JUnit 5 support • New docs & more examples • Env var to turn off Ryuk
 (for public CIs) • shm + TmpFS settings Nov, 2018 @bsideup
64. 1.10.x • JUnit 5 support • New docs & more examples • Env var to turn off Ryuk
 (for public CIs) • shm + TmpFS settings • Auto dependency updates
 with Dependabot Nov, 2018 @bsideup
65. 1.10.x • JUnit 5 support • New docs & more examples • Env var to turn off Ryuk
 (for public CIs) • shm + TmpFS settings • Auto dependency updates
 with Dependabot Nov, 2018 @bsideup
66. 1.10.x • JUnit 5 support • New docs & more examples • Env var to turn off Ryuk
 (for public CIs) • shm + TmpFS settings • Auto dependency updates
 with Dependabot • Neo4j and Elasticsearch modules Nov, 2018 @bsideup
67. 1.11.x Mar, 2019 @bsideup
68. 1.11.x • Chaos Testing (toxiproxy) Mar, 2019 @bsideup @Rule public GenericContainer redis = new GenericContainer("redis:5.0.4") .withExposedPorts(6379) .withNetwork(network); @Rule public ToxiproxyContainer toxiproxy = new ToxiproxyContainer() .withNetwork(network); @Test public void testLatencyViaProxy() throws IOException { ContainerProxy proxy = toxiproxy.getProxy(redis, 6379); Jedis jedis = new Jedis( proxy.getContainerIpAddress(), proxy.getProxyPort() ); proxy.toxics() .latency("latency", ToxicDirection.DOWNSTREAM, 1_100) .setJitter(100); jedis.get("somekey"); }
69. 1.11.x • Chaos Testing (toxiproxy) • fsync=off for PostgreSQL Mar, 2019 @bsideup
70. 1.11.x • Chaos Testing (toxiproxy) • fsync=off for PostgreSQL • Drop Netty transport Mar, 2019 @bsideup
71. 1.11.x • Chaos Testing (toxiproxy) • fsync=off for PostgreSQL • Drop Netty transport Mar, 2019 @bsideup
72. 1.11.x • Chaos Testing (toxiproxy) • fsync=off for PostgreSQL • Drop Netty transport • Rework shading Mar, 2019 @bsideup
73. Roadmap
74. new DSL
75. What’s wrong with the current one?
76. KafkaContainer kafka = new KafkaContainer() .withLogConsumer(new Slf4jLogConsumer(log)) .withEmbeddedZookeeper() .withEnv("FOO", "BAR") .withStartupAttempts(5); Current DSL @bsideup
77. KafkaContainer kafka = new KafkaContainer() .withLogConsumer(new Slf4jLogConsumer(log)) .withEmbeddedZookeeper() .withEnv("FOO", "BAR") .withStartupAttempts(5); Current DSL GenericContainer @bsideup
78. KafkaContainer kafka = new KafkaContainer() .withLogConsumer(new Slf4jLogConsumer(log)) .withEmbeddedZookeeper() .withEnv("FOO", "BAR") .withStartupAttempts(5); Current DSL KafkaContainer @bsideup
79. KafkaContainer kafka = new KafkaContainer() .withLogConsumer(new Slf4jLogConsumer(log)) .withEmbeddedZookeeper() .withEnv("FOO", "BAR") .withStartupAttempts(5); Current DSL GenericContainer @bsideup
80. KafkaContainer kafka = new KafkaContainer() .withLogConsumer(new Slf4jLogConsumer(log)) .withEmbeddedZookeeper() .withEnv("FOO", "BAR") .withStartupAttempts(5); Current DSL GenericContainer @bsideup
81. KafkaContainer kafka = new KafkaContainer() .withLogConsumer(new Slf4jLogConsumer(log)) .withEmbeddedZookeeper() .withEnv("FOO", "BAR") .withStartupAttempts(5); Current DSL GenericContainer public SELF withStartupAttempts(int attempts) { this.startupAttempts = attempts; return self(); } @bsideup
82. public class KafkaContainer extends GenericContainer<KafkaContainer> {} public class GenericContainer<SELF extends GenericContainer<SELF>> /* */ {} @bsideup
83. public class KafkaContainer extends GenericContainer<KafkaContainer> {} public class GenericContainer<SELF extends GenericContainer<SELF>> /* */ {} https://youtrack.jetbrains.com/issue/KT-17186 https://stackoverflow.com/questions/39163749/how-to-use-a-java-self-bounded-class-in-scala @bsideup
84. ❌ Hard to maintain @bsideup
85. ❌ Hard to maintain ❌ Does not work with Kotlin/Scala @bsideup
86. ❌ Hard to maintain ❌ Does not work with Kotlin/Scala ❌ Externally mutable objects @bsideup
87. ❌ Hard to maintain ❌ Does not work with Kotlin/Scala ❌ Externally mutable objects ❌ “setX” isn’t supported, only “withX” (think collections) @bsideup
88. ❌ Hard to maintain ❌ Does not work with Kotlin/Scala ❌ Externally mutable objects ❌ “setX” isn’t supported, only “withX” (think collections) ❌ No imperative “if-else” with the fluent style @bsideup
89. KafkaContainer kafka = new KafkaContainer() { @Override protected void initialize() { withLogConsumer(new Slf4jLogConsumer(log)); withEmbeddedZookeeper(); withEnv("FOO", "BAR"); withStartupAttempts(5); } }; New “DSL”? @bsideup
90. KafkaContainer kafka = new KafkaContainer() { @Override protected void initialize() { withLogConsumer(new Slf4jLogConsumer(log)); withEmbeddedZookeeper(); withEnv("FOO", "BAR"); withStartupAttempts(5); } }; New “DSL”? Or even… @bsideup
91. KafkaContainer kafka = new KafkaContainer() {{ withLogConsumer(new Slf4jLogConsumer(log)); withEmbeddedZookeeper(); withEnv("FOO", "BAR"); withStartupAttempts(5); }} New “DSL”? @bsideup
92. KafkaContainer kafka = new KafkaContainer() {{ withLogConsumer(new Slf4jLogConsumer(log)); withEmbeddedZookeeper(); withEnv("FOO", "BAR"); withStartupAttempts(5); }} New “DSL”? public void withStartupAttempts(int attempts) { this.startupAttempts = attempts; } @bsideup
93. KafkaContainer kafka = new KafkaContainer() {{ withLogConsumer(new Slf4jLogConsumer(log)); withEmbeddedZookeeper(); withEnv("FOO", "BAR"); withStartupAttempts(5); }} New “DSL”? public void withStartupAttempts(int attempts) { this.startupAttempts = attempts; } @bsideup
94. ✓ Super easy to maintain @bsideup
95. ✓ Super easy to maintain ✓ Works with any JVM language @bsideup
96. ✓ Super easy to maintain ✓ Works with any JVM language ✓ “Controllable mutability” - no modifications outside of “initialize” @bsideup
97. ✓ Super easy to maintain ✓ Works with any JVM language ✓ “Controllable mutability” - no modifications outside of “initialize” ✓ Void-retuning “setX” can easily be used @bsideup
98. ✓ Super easy to maintain ✓ Works with any JVM language ✓ “Controllable mutability” - no modifications outside of “initialize” ✓ Void-retuning “setX” can easily be used ✓ Can use “if-else” @bsideup
99. GraalVM focus
100. @bsideup https://medium.com/graalvm/using-testcontainers-from-a-node-js- application-3aa2273bf3bb
101. @bsideup // JavaScript var GenericContainer = Java.type(’org.testcontainers.containers.GenericContainer’); var container = new GenericContainer("nginx"); container.setExposedPorts([80]); container.start(); console.log(container.getContainerIpAddress() + ‘:’ + container.getMappedPort(80)); https://medium.com/graalvm/using-testcontainers-from-a-node-js- application-3aa2273bf3bb
102. @bsideup // JavaScript var GenericContainer = Java.type(’org.testcontainers.containers.GenericContainer’); var container = new GenericContainer("nginx"); container.setExposedPorts([80]); container.start(); console.log(container.getContainerIpAddress() + ‘:’ + container.getMappedPort(80)); https://medium.com/graalvm/using-testcontainers-from-a-node-js- application-3aa2273bf3bb // Python import java generic = java.type('org.testcontainers.containers.GenericContainer') container = generic('nginx') container.setExposedPorts([80]) container.start(); print('%s:%s' % (container.getContainerIpAddress(), container.getMappedPort(80)));
103. “container core”
104. Testcontainers 1.x architecture Core
 (Docker, GenericContainer, 
 JUnit 4 int, test lifecycle) @bsideup
105. Testcontainers 1.x architecture Core
 (Docker, GenericContainer, 
 JUnit 4 int, test lifecycle) JUnit Jupiter int. @bsideup
106. Testcontainers 1.x architecture Core
 (Docker, GenericContainer, 
 JUnit 4 int, test lifecycle) JUnit Jupiter int. Modules like MySQL/Kafka/… @bsideup
107. Testcontainers 2.x architecture Container-core
 (GenericContainer) @bsideup
108. Testcontainers 2.x architecture Container-core
 (GenericContainer) Test Frameworks JUnit 4 JUnit Jupiter Scala test? … @bsideup
109. Testcontainers 2.x architecture Container-core
 (GenericContainer) Test Frameworks JUnit 4 JUnit Jupiter Scala test? … Executing engines Container-core-docker
 (env discovery, networks, …) Container-core-k8s? … @bsideup
110. Modules like MySQL/Kafka/… Testcontainers 2.x architecture Container-core
 (GenericContainer) Test Frameworks JUnit 4 JUnit Jupiter Scala test? … Executing engines Container-core-docker
 (env discovery, networks, …) Container-core-k8s? … @bsideup
112. Usability Flexibility Speed Features @bsideup
113. Usability Flexibility Speed Features @bsideup
114. Usability Flexibility Speed Features @bsideup
115. Please welcome…
116. Reusable containers
117. Reusable containers
118. Demo
119. @bsideup
120. ✓ Ultra-fast ITDD (Integration Test Driven Development) @bsideup
121. ✓ Ultra-fast ITDD (Integration Test Driven Development) ✓ Minimal effort for the users @bsideup
122. ✓ Ultra-fast ITDD (Integration Test Driven Development) ✓ Minimal effort for the users ✓ Works for most of the containers @bsideup
123. ✓ Ultra-fast ITDD (Integration Test Driven Development) ✓ Minimal effort for the users ✓ Works for most of the containers ✓ Eventually cleanups stale containers
 (unlike Docker Compose) @bsideup
124. ✓ Ultra-fast ITDD (Integration Test Driven Development) ✓ Minimal effort for the users ✓ Works for most of the containers ✓ Eventually cleanups stale containers
 (unlike Docker Compose) ✓ Available later this year. Pre-order now for $0 @bsideup
125. Takeaways • https://testcontainers.org • Works on Linux, Mac and Windows • …including CIs like Jenkins, Travis, CircleCI, BitBucket, AzurePipelines, … • Provides a great balance between 
 flexibility, usability, speed and features
 @bsideup
126. @bsideup bsideup