testcontainers / workshop

Introduction

This workshop will explain how to use Testcontainers (https://www.testcontainers.com) in your Java applications.

We'll build a sample Spring Boot application, add tests to it, and explore Testcontainers for Java API you need to know to be effective with your tests.

Table of contents

• Introduction
• Step 1: Getting Started
• Step 2: Exploring the app
• Step 3: Adding some tests
• Step 4: Your first Testcontainers integration
• Step 5: Hello, r u 200 OK?
• Step 6: Adding Redis
• Step 7: Test the API
• Step 8: Local Development Environment with Testcontainers

Next steps which you can do in any order based on the interest:

• Edge cases
• Data initialization strategies
• Migrating from Docker Compose
• Chaos Engineering
• Custom Modules

workshop's Issues

Workshop Missing details on configuring Kafka

Kafka config not clear

The only thing written is

"Running Kafka in Docker is easy with TestContainers. There is a Testcontainers module providing integration with Kafka and the KafkaContainer abstraction for your code.

Just add it the same way as you added Redis and set the spring.kafka.bootstrap-servers system property.

I tried to do as instructed but the tests are failing.

static final GenericContainer<?> kafka = new GenericContainer("confluentinc/cp-kafka:5.4.6").withExposedPorts(9092);

And in the DynamicPropertySource annotation I wrote

@DynamicPropertySource
public static void configureRedisKafka(DynamicPropertyRegistry registry) {
    Stream.of(redis,kafka).parallel().forEach(GenericContainer::start);
    registry.add("spring.redis.host", redis::getHost);
    registry.add("spring.redis.port", redis::getFirstMappedPort);
    registry.add("spring.kafka.bostrap-servers", kafka::getHost);
}

Thus, what is the correct solution?

Add notice in step 3 that port must be available

I'm just going through the workshop and failed at step 3 "Our very first test" running the dummy test com.example.demo.DemoApplicationTest because the build in tomcat webserver could not be estabilshed.

It turned out that I had to stop Docker Desktop which was running in parallel. So I think they used the same port (8000 or 8080 as these were used by Docker).

I think there should be a note in the description. It may sounds obvious if you are familiar with Spring (which I never had worked with), but as someone like me who started with the official docker tutorial may get struck.

edit:
Maybe add the environment requirements in the workshop - what software has to be installed (and maybe how)

Licensing and reusing

Working on my Testcontainers presentation I wanted to create a sample/simple application with some use cases for the live coding section. However, in the meantime, I have found this workshop. I wonder what is the license of that project and can I use it and adapt to my needs (such as a variant in Spock or JUnit 5)?

Of course with the proper attribution where does this project come from.