Support a method to directly ingest logs from the S3 bucket of Security Lake

[valmet083]

Summary

To ingest logs from Security Lake, it is necessary to obtain the logs through a subscriber with the method described in the documentation below. Having a method to manually ingest specific logs can provide greater flexibility for log investigation. https://github.com/aws-samples/siem-on-amazon-opensearch-service/blob/main/docs/securitylake.md

Usecase

• Considering the cost, we have set the log retention period for SIEM on Amazon OpenSearch Service to 90 days.
• The S3 bucket and the SIEM on Amazon OpenSearch Service are on the same AWS account.
• We want to be able to import logs from the Security Lake's S3 bucket and analyze logs that have exceeded the retention period when necessary.