Embedded Redis for Spring Boot

Question

I run my Integration Test cases with Spring Boot with the help of my local Redis server on my machine.

But I want an embedded Redis server which is not dependent on any

Answer 1

Another neat way is to use the testcontainers library which can run any type of application that can in a Docker container and Redis is no exception. What I like best is that it is lightly coupled with the Spring Test ecosystem.

maven's dependency:

    org.testcontainers
    testcontainers
    ${testcontainers.version}

simple integration test:

@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT, properties = {"management.port=0"})
@ContextConfiguration(initializers = AbstractIntegrationTest.Initializer.class)
@DirtiesContext
public abstract class AbstractIntegrationTest {

    private static int REDIS_PORT = 6379;

    @ClassRule
    public static GenericContainer redis = new GenericContainer("redis:5-alpine").withExposedPorts(REDIS_PORT);

    public static class Initializer implements ApplicationContextInitializer {
        @Override
        public void initialize(ConfigurableApplicationContext ctx) {
            // Spring Boot 1.5.x
            TestPropertySourceUtils.addInlinedPropertiesToEnvironment(ctx,
                "spring.redis.host=" + redis.getContainerIpAddress(),
                "spring.redis.port=" + redis.getMappedPort(REDIS_PORT));

            // Spring Boot 2.x.
            TestPropertyValues.of(
                "spring.redis.host:" + redis.getContainerIpAddress(),
                "spring.redis.port:" + redis.getMappedPort(REDIS_PORT))
                .applyTo(ctx);
        }
    }
}

Since Spring Framework 5.2.5 (Spring Boot 2.3.x) you can use the powerful DynamicPropertySource annotation. Here is an example:

@ExtendWith(SpringExtension.class)
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
@DirtiesContext(classMode = DirtiesContext.ClassMode.AFTER_CLASS)
public abstract class AbstractIT {

    static GenericContainer redisContainer = new GenericContainer("redis:5-alpine").withExposedPorts(6379);

    @DynamicPropertySource
    static void properties(DynamicPropertyRegistry r) throws IOException {
        r.add("spring.redis.host", redisContainer::getContainerIpAddress);
        r.add("spring.redis.port", redisContainer::getFirstMappedPort);
    }
}