How do I set up LocalStackContainer for KMS using the AWS Java SDK v2?

Question

My KMSClient is being instantiated way before LocalStack is started and I don't know how I should initialise my KmsClientBuilder to override the endpoint.

KmsClient.builder().endpointOverride("some sort of static value")).build();

LocalStackContainer = new LocalStackContainer(DockerImageName.parse("localstack/localstack:2.3.0").withServices(LocalStackContainer.Service.KMS)

Answer 1

You should instantiate the LocalStack container first before trying to create a KMS client.

Then as per docs, you need to instantiate your client(s) with the right:

• endpoint
• credentials
• region

For KMS (and other clients), this should work:

import org.testcontainers.containers.localstack.LocalStackContainer;
import org.testcontainers.utility.DockerImageName;
import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.kms.KmsClient;
...

DockerImageName image = DockerImageName.parse("localstack/localstack:2.3.0");

LocalStackContainer container = new LocalStackContainer(image)
        .withServices(LocalStackContainer.Service.KMS);

KmsClient client = KmsClient.builder()
        .endpointOverride(container.getEndpoint())
        .credentialsProvider(
                StaticCredentialsProvider.create(
                        AwsBasicCredentials.create(container.getAccessKey(), container.getSecretKey())
                )
        )
        .region(Region.of(container.getRegion()))
        .build();