HDDS-15304. DeleteObjects should enforce the request key limit

[sreejasahithi]

What changes were proposed in this pull request?

The multi object delete iterates all request entries and forwards them to bucket.deleteKeys without checking the S3 1000 key maximum limit.
It should reject DeleteObjects requests with more than 1000 objects before execution and return the error.

What is the link to the Apache JIRA

HDDS-15304

How was this patch tested?

Added testcases
Green CI : https://github.com/sreejasahithi/ozone/actions/runs/26077522597

[sreejasahithi]

@peterxcli could you please review this patch.

[peterxcli]

LGTM +1
https://docs.aws.amazon.com/AmazonS3/latest/API/API_DeleteObjects.html#:~:text=The%20request%20can%20contain,you%20want%20to%20delete

[sreejasahithi]

Sample output after the fix.

bash-5.1$ 
bash-5.1$ 
bash-5.1$ aws s3api delete-objects \
 --bucket test-delete-limit \
 --delete "$(python3 -c "
import json
keys = [{'Key': f'key-{i}'} for i in range(1, 1002)]
print(json.dumps({'Objects': keys, 'Quiet': False}))
")" \
 --endpoint-url http://localhost:9878/

An error occurred (MalformedXML) when calling the DeleteObjects operation: The XML you provided was not well-formed or did not validate against our published schema
bash-5.1$ 
bash-5.1$ 
bash-5.1$ aws s3api delete-objects \
 --bucket test-delete-limit \
 --delete "$(python3 -c "
import json
keys = [{'Key': f'key-{i}'} for i in range(1, 1000)]
print(json.dumps({'Objects': keys, 'Quiet': False}))
")" \
 --endpoint-url http://localhost:9878/
{
  "Deleted": [
    {
      "Key": "key-1"
    },
    {
      "Key": "key-2"
    },
    {
      "Key": "key-3"
    },
    {
      "Key": "key-4"
    },
    {
      "Key": "key-5"
    },
    {
      "Key": "key-6"
    },
    {
      "Key": "key-7"
    },
    {
      "Key": "key-8"
    },
    {
      "Key": "key-9"

[peterxcli]

I think we should throw clear exception

Suggested change

	throw newError(S3ErrorTable.MALFORMED_XML, bucketName);
	throw newError(S3ErrorTable.INVALID_ARGUMENT, "too many objects");

[adoroszlai]

Test case multiDeleteRejectsMoreThanMaxKeysPerRequest will need to be updated as well.

[sreejasahithi]

I think it would be better to keep MALFORMED_XML and maybe add reason along with it instead of INVALID_ARGUMENT
aws/aws-sdk#602 (comment)

[sreejasahithi]

@peterxcli could you please let me know which would be better to have INVALID_ARGUMENT or MALFORMED_XML because looks like aws uses MALFORMED_XML not sure if it later changed it.
we could probably update the message like follows:

throw newError(S3ErrorTable.MALFORMED_XML, bucketName)
.withMessage(S3ErrorTable.MALFORMED_XML.getErrorMessage()
+ ". A maximum of " + S3Consts.S3_DELETE_OBJECTS_MAX_KEYS
+ " objects may be specified per request.");

[peterxcli]

@sreejasahithi thanks for providing the specific issue link, after take deeper look I think you're right.

The existing ceph s3-test test case only assert the http code
https://ozone.s3.peterxcli.dev/?q=delete_bucket&run=2026-06-15T07-46-21Z&caseSuite=s3_tests&test=test_multi_object_delete_key_limit#search-section

I've checked the minio archive code, and it indeed return MALFORMED_XML for this delete object limit exceed case.
https://github.com/minio/minio/blob/7aac2a2c5b7c882e68c1ce017d8256be2feea27f/cmd/bucket-handlers.go#L472-L476

[adoroszlai]

nit: can simplify using EndpointTestUtils.assertErrorResponse

assertErrorResponse(S3ErrorTable.INVALID_ARGUMENT, () -> rest.multiDelete("b1", "", mdr));

(changed error code suggested by @peterxcli)

[peterxcli]

Thanks @sreejasahithi for the update, LGTM +1

[peterxcli]

@sreejasahithi thanks for providing the specific issue link, after take deeper look I think you're right.

The existing ceph s3-test test case only assert the http code
https://ozone.s3.peterxcli.dev/?q=delete_bucket&run=2026-06-15T07-46-21Z&caseSuite=s3_tests&test=test_multi_object_delete_key_limit#search-section

I've checked the minio archive code, and it indeed return MALFORMED_XML for this delete object limit exceed case.
https://github.com/minio/minio/blob/7aac2a2c5b7c882e68c1ce017d8256be2feea27f/cmd/bucket-handlers.go#L472-L476

[peterxcli]

Thanks @sreejasahithi for the patch, @adoroszlai for the review!