fix: automatically cleanup ZeebeVolumes

[lenaschoenburg]

Accesses the internal of testcontainers-java to apply the correct label to ZeebeVolumes such that Ryuk (or an alternative ResourceReaper) can find the volume and automatically remove it after tests are done.

The tests are a bit hacky because we use reflection to get to the private implementations of ResourceReaper.

Closes #656

[npepinpe]

I guess this means it's at risk of being removed, or at least hidden? 🤔

[npepinpe]

Instead of relying on an internal API, what about adding our own marker label? So we keep adding the default labels, but then add our own label (e.g. io.camunda.zeebe.sessionId), and register it via

public final class ZeebeVolume {
  private static final String SESSION_LABEL = "io.zeebe.containers.sessionId";
  private static final Map<String, String> MARKER_LABELS = Collections.singletonMap(SESSION_LABEL, DockerClientFactory.SESSION_ID);

  static {
    ResourceReaper.instance().registerLabelsFilterForCleanup(MARKER_LABELS);
  }

  public static ZeebeVolume newVolume(final UnaryOperator<CreateVolumeCmd> configurator) {
    final DockerClient client = DockerClientFactory.instance().client();
    try (final CreateVolumeCmd command = client.createVolumeCmd()) {
      final Map<String, String> labels = new HashMap<String, String>(DockerClientFactory.DEFAULT_LABELS);
      labels.putAll(MARKER_LABELS);

      final CreateVolumeResponse response = configurator.apply(command.withLabels(labels).exec();
      return new ZeebeVolume(response.getName(), client);
    }
  }

[npepinpe]

This also means we won't need reflection in the test to check if everything is working as expected.

[lenaschoenburg]

Ah right, that's how this is supposed to work 🤦

Although I don't see how this removes the need for reflection in the tests. We'd still want to test that the container is actually removed, right?

[lenaschoenburg]

Yes, that's exactly what getCleanupRunnable does, right?

[npepinpe]

I thought maybe that part is not necessary?

        final Method performCleanup = reaperClass.getDeclaredMethod("performCleanup");
        performCleanup.setAccessible(true);
        performCleanup.invoke(reaper);

🤷 It's really minor anyway

[lenaschoenburg]

Ah yeah that works 👍

[lenaschoenburg]

Registering the new labels with Ryuk does work btw:

[testcontainers-ryuk] DEBUG org.testcontainers.utility.ResourceReaper - Sending 'label=io.zeebe.containers.sessionId%3D85662216-fce6-4aab-a7c1-fe9afd3e3419' to Ryuk

[npepinpe]

Cool, we can make use of that when they remove the deprecated API 😄

[npepinpe]

I guess I should update the build system to allow running with DinD even without a TCC token 😄

[npepinpe]

In the spirit of laziness, let's merge it and fix any issues after once tests are running automatically 🤘