Steadybit Testcontainers

What is it?

Steadybit Testcontainers is a helper library to the Testcontainers Project to implement Resilience Tests.

Getting Started

We have a blog post discussing "Resilience Tests with Testcontainers" which gives a more detailed explanation.

1. Add Steadybit Testcontainers to your project:

Add this to the test dependencies in your pom.xml:

<dependency>  
  <groupId>com.steadybit</groupId>
  <artifactId>steadybit-testcontainers</artifactId>
  <version>1.0.1</version>
  <scope>test</scope>
</dependency>

2. Add some Chaos to your Testcontainers Test:

Here is an example for delaying the Redis traffic:

@Testcontainers
public class RedisBackedCacheIntTest {
    private RedisBackedCache underTest;

    @Container
    public GenericContainer redis = new GenericContainer(DockerImageName.parse("redis:5.0.3-alpine")).withExposedPorts(6379);

    @BeforeEach
    public void setUp() {
        underTest = new RedisBackedCache(redis.getHost(), redis.getFirstMappedPort());
    }

    @Test
    public void testFindingAnInsertedValue() {
        underTest.put("foo", "FOO");

        Optional<String> foundObject = Steadybit.networkDelayPackages(Duration.ofSeconds(2))
                .forContainers(redis)
                .exec(() -> {
                    //this code runs after the attack was started.
                    //As soon as this lambda exits the attack will be stopped.
                    return underTest.get("foo", String.class);
                });

        assertTrue("When an object in the cache is retrieved, it can be found", foundObject.isPresent());
        assertEquals("When we put a String in to the cache and retrieve it, the value is the same", "FOO", foundObject.get());
    }
}

Available Attacks

networkDelayPackages: Delays egress tcp/udp network packages for containers (on eth0 by default)
networkLoosePackages: Looses egress tcp/udp network packages for containers (on eth0 by default)
networkCorruptPackages: Corrupts egress tcp/udp network packages for containers (on eth0 by default)
networkLimitBandwidth: Limits tcp/udp network bandwidth for containers (on eth0 by default)
networkBlackhole: Blocks all network traffic for containers
networkBlockDns: Blocks all network traffic for containers on dns port (53)

steadybit / testcontainers