Description
Is there an existing issue for this?
- I have searched the existing issues
Current Behavior
I uploaded a file to an S3 bucket in my Localstack server using multipart features with checksum enabled. The upload generated three parts. After the end of the process, the command
awslocal s3api get-object-attributes --bucket test-bucket --key file.txt --object-attributes Checksum ObjectParts
returns:
{
"LastModified": "Sun, 15 Jun 2025 04:33:36 GMT",
"Checksum": {
"ChecksumSHA256": "R6zkFE4j0YnCkZJk/cJ+dI+Z/BcS9Ug1g+p3VNqF5Ik=",
"ChecksumType": "COMPOSITE"
},
"ObjectParts": {
"TotalPartsCount": 3
}
}
Expected Behavior
The expected return is something like this:
{
"LastModified": "Sun, 15 Jun 2025 04:33:36 GMT",
"Checksum": {
"ChecksumSHA256": "R6zkFE4j0YnCkZJk/cJ+dI+Z/BcS9Ug1g+p3VNqF5Ik=",
"ChecksumType": "COMPOSITE"
},
"ObjectParts": {
"TotalPartsCount": 3,
"Parts": [
{
"PartNumber": 1,
"Size": 5242880,
"ChecksumSHA256": "abc123..."
},
{
"PartNumber": 2,
"Size": 5242880,
"ChecksumSHA256": "def456..."
},
{
"PartNumber": 3,
"Size": 1048576,
"ChecksumSHA256": "ghi789..."
}
]
}
}
How are you starting LocalStack?
I have executed a JUnit test with Testcontainers, implementing my custom container for S3
Steps To Reproduce
this is a fragment of the testcontainer implementation:
public class S3Container
extends LocalStackContainer
{
private static final String LOCALSTACK = "localstack";
private static final String IMAGE_NAME = "%1$s/%1$s:4.5.0".formatted(LOCALSTACK);
...
private static final String GET_OBJECT_ATTRIBUTES_COMMAND = "awslocal s3api get-object-attributes --bucket %s --key %s --object-attributes %s %s";
...
public String checksum(String bucketName, String key)
{
String result;
Object[] array = {bucketName, key, "Checksum", "ObjectParts"};
var command = GET_OBJECT_ATTRIBUTES_COMMAND.formatted(array);
try (var jsonb = JsonbBuilder.create())
{
var output = execInContainer("sh", "-c", command);
var message = "Failed to retrieve the checksum of object %s in bucket %s";
Assertions.assertEquals(0, output.getExitCode(), message.formatted(key, bucketName));
var attributes = jsonb.fromJson(output.getStdout(), ObjectAttributes.class);
result = attributes.checksum().checksumSha256();
}
catch (InterruptedException x)
{
Thread.currentThread().interrupt();
result = Assertions.fail(x);
}
catch (Exception x)
{
result = Assertions.fail(x);
}
return result;
}
...
}
Invoke this method after having created a bucket and uploaded a file with multipart and checksum enabled using your preferred API.
Attached you can find the usage of all the phases of the multipart upload through the Java AWS SDK and the status of the debugger when the upload is going to complete. Checksums of every parts have been calculated as expected.
Environment
- OS:
- LocalStack: Community
LocalStack version: 4.5.0
LocalStack Docker image sha: localstack/localstack:4.5.0
LocalStack build date: 2025, 5th of JuneAnything else?
In order to check that my Java multipart upload has been successfully completed, I want to calculate the checksum of my local file applying the same algorithm explained here. Expand the "Using the AWS SDKs" section and see the method validateExistingFileAgainstS3Checksum for further details.