JBCN_Testing_With_Containers
- 1. © 2021 IBM Corporation Replicating production on your laptop using the magic of containers Grace Jansen Developer Advocate @gracejansen27
- 2. Why do we write automated tests?
- 3. To have confidence that our applications work the way we want them to!
- 4. System/ UI testing Integration testing UnitTesting Types of testing
- 5. ManualTesting if I have time and remember Integration testing UnitTesting What we have time to do
- 6. Problem with just using Unit tests Tap turns on Tap turns off Drain works Sink does not overflow
- 8. The Magic of Containers • Virtualization from OS level • Lightweight • Faster start-up • Portable with images and config files such as a Dockerfile • Run Anywhere • Isolation • Complexity!
- 9. The Magic of Kubernetes • Automated rollouts and rollbacks • Automatic scaling of services (containers) • Health monitoring • Declarative management • Deploy anywhere (Hybrid deployments)
- 10. What Magic can Developers use? • Isolated development environments • Portable • Preconfigured images available • Fast start-up of applications • No need to have so many pre-reqs installed • Version control of dependencies • Can develop easily in the cloud • True-to production testing!
- 11. What Magic can Developers use? • Isolated development environments • Portable • Preconfigured images available • Fast start-up of applications • No need to have so many pre-reqs installed • Version control of dependencies • Can develop easily in the cloud • True-to production testing!
- 12. 1. Codebase 2. Dependencies 3. Config 4. Backing Services 5. Build, Release, Run 6. Stateless Processes 7. Port Binding 8. Concurrency 9. Disposability 10. Dev-Prod Parity 11. Logs 12. Admin processes
- 13. Dev-Prod Parity Keep development, staging, and production as similar as possible Comprised of three common issues: • The time gap • The personnel gap • The tools gap “The twelve-factor developer resists the urge to use different backing services between development and production, even when adapters theoretically abstract away any differences in backing services.”
- 15. Testing Problems that Containers can solve • Data access such access to databases • Integration testing • Automatic updating and version control • Complex setup on local machines • Portable testing environments (So others can run the same test easily) • …
- 17. my- app:latest (app container) mongo:4.0 (DB container) Dev/Test env Production env integration tests end users my- app:latest (app container) mongo:4.0 (DB container) Testcontainers • Integration tests that are easy to setup, write, and run • Test your apps the same way they run in production • Tests are portable to any compatible implementation: • Liberty • Wildfly • Payara • TomEE • etc…
- 18. AvailableTestcontainer Modules: Database Modules: • CouchBase • DB2 • MongoDB • MySQL • Postgress etc Other Modules: • Docker Compose • Elasticsearch • Kafka • Nginx • RabbitMQ
- 20. What is MicroShedTesting? The MicroshedTesting framework allows for true-to-production integration tests on your local machine.This enables you as a developer to minimize the amount of test failures due to differences in dev/test and production environments. Using the magic of containers, you can replicate what you have in your production environment without much setup at all.
- 21. MicroShed Example @MicroShedTest public class MyTest { // Search for Dockerfile. // Start app in Container. // Wait for Container before running tests. @Container public static MicroProfileApplication app = new MicroProfileApplication() .withAppContextRoot("/myservice"); // Inject JAX-RS REST Client @RestClient public static MyService mySvc; // A test method like any other @Test public void testMyService() { ... } } The @MicroShedTest annotation is required so that the build knows this is a MicroShed test The @Container annotation is required for setting up your container to run your tests inside The @RESTClient annotation is needed to give us something to test against The @Test annotation like you would in a normal JUnit test.
- 22. SharableConfiguration If multiple test classes can share the same container instances, they can offload their @Container annotated fields to a sperate class like so: public class AppContainerConfig implements SharedContainerConfiguration { @Container public static ApplicationContainer app = new ApplicationContainer() .withAppContextRoot("/myservice"); } @MicroShedTest @SharedContainerConfig(AppContainerConfig.class) public class MySimpleTestA { // ... } @MicroShedTest @SharedContainerConfig(AppContainerConfig.class) public class MySimpleTestB { // ... }
- 23. Different RuntimesAvailable • Open Liberty • Payara Micro • Payara Sever • Wildfly • Quarkus
- 24. True to production testing with MicroShed Testing
- 27. Interactive Demo Turning a JUnit test into a MicroShed test If you would like to follow along at the same time please go to the following link and select the “Testing a MicroProfile or Jakarta EE Application” Module https://openliberty.skillsnetwork.site/cloud-native-java-made- easy-microprofile-jakarta-ee
- 28. Summary • Containers are great! • They make developers lives easier (portable, configurable, lightweight…) • They can help solve some issues with testing such as dev/test prod parity • There are some great open source tools available to utilise testing with containers • Helps speed up time to production, making everyone happier!
- 29. Resources: • Run true-to-production tests on your MicroProfile and JakartaEE applications - https://developer.ibm.com/languages/java/articles/true-to-production-testing- microprofile-jakarta-ee/ • Five Java frameworks for improving your automated testing - https://developer.ibm.com/devpractices/continuous-delivery/blogs/five-frameworks-for- improving-your-java-automated-tests/ • Open Liberty - https://openliberty.io • MicroShed - https://microshed.org • Testcontainers - https://www.testcontainers.org/ • MicroProfile - https://microprofile.io/ • Jakarta EE - https://jakarta.ee/