Enhanced Testcontainers Support

[mbechto]

We were trying to use the mq-container with Spring Boot 3.x Testcontainers with @ServiceConnection similar to what you can do with a PostgreSQL container:

@TestConfiguration(proxyBeanMethods = false)
public class TestcontainersConfiguration {
  @Bean
  @ServiceConnection
  @RestartScope
  PostgreSQLContainer<?> postgresContainer() {
    return new PostgreSQLContainer<>(DockerImageName.parse("postgres:latest"));
  }
}

Our intention is to avoid unnecessary container restarts between @SpringBootTests as that slows down the testing process significantly therefore @RestartScope. Maybe more importantly @ServiceConnection configures the correct connection properties, since Testcontainers exposes services on a random port (by default) this is crucial. So similar to PostgreSQL, we tried something like this:

@TestConfiguration(proxyBeanMethods = false)
public class TestcontainersConfiguration {
  @Bean
  @ServiceConnection
  @RestartScope
  GenericContainer<?> ibmMqTestContainer() {
    return new GenericContainer<>(DockerImageName.parse("ibm-messaging/mq-container:latest"));
  }
}

Resulting in the following error on startup:

org.springframework.boot.autoconfigure.service.connection.ConnectionDetailsNotFoundException: No ConnectionDetails found for source '@ServiceConnection source for Bean 'ibmMqTestContainer' defined in class path resource [TestcontainersConfiguration.class]'. You may need to add a 'name' to your @ServiceConnection annotation

After some debugging through Spring code, I guess this would require some integration to make it work, e.g. implementing some classes similar to the ActiveMQ Testcontainers integration.

• ibmmq-jms-spring version: 3.3.1
• Java version (including vendor and platform): Temurin-21.0.3+9
• A small code sample that demonstrates the issue.

[mbechto]

Hi @ibmmqmet, I forked the repository and had a go at implementing a very rudimentary PoC (see mbechto@30768a3), but maybe that gives an idea of the changes in order to achieve this. These are:

• Extend the ConnectionDetails interface, allowing to provide alternative (to the properties) connection details
• Using those as a preferred way of configuring the MQConnectionFactory, while falling back to properties
• Implementing a factory that creates MQConnectionDetails sourced from the containers mapped random port
• In order for that to work, implement an MQContainer

I have added an integration test to further illustrate the use case: https://github.com/mbechto/mq-jms-spring/blob/30768a386c7ca9436d49da3b3260d000e44788ee/mq-jms-spring-boot-starter/src/test/java/com/ibm/mq/spring/boot/TestcontainersTest.java

Caveats

• This requires Spring Boot 3, since 2 is missing the ConnectionDetails interface. It won't build with Spring Boot 2...
• Architecturally, the Testcontainers related classes should reside in their own library or even upstream in spring-boot-starter-testcontainers
• MQContainer is very rudimentary and needs more configuration options
• Backward compatibility: I think I managed to keep the public static methods backward compatible, but I could have made a mistake along the way...

[eddumelendez]

Hi, spring boot 3.1 should be required in order to support ConnectionDetails and ServiceConnection

[mbechto]

Hi @eddumelendez, thanks for the heads up! That's right. As I pointed out in my caveats section, the PoC I wrote does not support Spring 2 due to what you mentioned. So that poses a problem, which is one reason why I didn't create a PR from my fork yet.

[ibmmqmet]

Thanks for raising this. It looks like it might be interesting. I plan to dig deeper into it when I get some time. Without looking at all yet, one thing I want to be wary of is any bloat in the dependency chains.