Testing with Testcontainers

This guide covers how to test TPF applications with a focus on unit tests and integration tests using Testcontainers.

Goals

• Keep business logic tests fast and deterministic.
• Use Testcontainers only when you need real dependencies (Postgres, Redis, external services).
• Separate framework development tests from application tests.

Unit Tests (No Containers)

For unit tests, keep the step logic isolated and mock dependencies where possible.

@QuarkusTest
class ProcessPaymentServiceTest {

  @Inject
  ProcessPaymentService service;

  @Test
  void processesPayment() {
    PaymentRecord record = new PaymentRecord("id-1", BigDecimal.TEN);
    Uni<PaymentStatus> result = service.process(record);
    UniAssertSubscriber<PaymentStatus> subscriber =
        result.subscribe().withSubscriber(UniAssertSubscriber.create());
    PaymentStatus status = subscriber.awaitItem().getItem();
    assertNotNull(status);
    assertNull(subscriber.getFailure());
  }
}

Integration Tests with Testcontainers

Use Testcontainers when you need real infrastructure. The pattern below uses Postgres and Redis as examples.

public class PostgresRedisResource implements QuarkusTestResourceLifecycleManager {

  private PostgreSQLContainer<?> postgres;
  private GenericContainer<?> redis;

  @Override
  public Map<String, String> start() {
    postgres = new PostgreSQLContainer<>("postgres:17");
    redis = new GenericContainer<>("redis:7-alpine").withExposedPorts(6379);

    postgres.start();
    redis.start();

    return Map.of(
        "quarkus.datasource.jdbc.url", postgres.getJdbcUrl(),
        "quarkus.datasource.username", postgres.getUsername(),
        "quarkus.datasource.password", postgres.getPassword(),
        "quarkus.redis.hosts", "redis://" + redis.getHost() + ":" + redis.getMappedPort(6379)
    );
  }

  @Override
  public void stop() {
    if (redis != null) {
      redis.stop();
    }
    if (postgres != null) {
      postgres.stop();
    }
  }
}

@QuarkusTest
@QuarkusTestResource(value = PostgresRedisResource.class, restrictToAnnotatedClass = true)
class PersistenceIntegrationIT {

  @Inject
  PaymentRepository repository;

  @Test
  void persistsRecords() {
    PaymentEntity entity = new PaymentEntity("id-1", BigDecimal.TEN);
    repository.persist(entity);
    assertTrue(repository.findByIdOptional("id-1").isPresent());
  }
}

Running Tests

./mvnw test

./mvnw verify

./mvnw test runs the fast test phase and is the right home for unit tests such as *Test. ./mvnw verify includes the verify phase, where integration tests such as *IT and container-backed checks should run.

Tips

• Prefer unit tests for step logic, reserve containers for persistence, cache, or orchestration tests.
• Keep container startup localized to integration tests to avoid slowing down unit test runs.
• If you need to run container-backed tests in CI, make sure Docker is available and stable.

Framework vs Application Tests

Application tests (this guide) focus on your pipeline behavior. If you are contributing to the framework itself, use the maintainer guide at Testing Guidelines.