get /api/{cluster}/topic/last-record fails when topic has only a single record

[xhedoja]

The current implementation of getLastRecord in RecordRepository only works if a topic has more than one record. For topics only one record there is, no result because the code does endOffset - 2 and then performs a single poll. If the partition only contains one record, this logic skips it.

Steps to Reproduce:

• Create a topic with only one partition.
• Produce a single message to that topic.
• Call get /api/{cluster}/topic/last-record for said record
• Empty response returned

[MusaabAlfalahi]

Hi @xhedoja,

I was exploring the codebase and came across this issue you described regarding getLastRecord and single-record topics. I looked into it and ran some tests, and it seems that the current implementation actually handles single-record topics correctly.

The code seeks to Math.max(0, offset - 2), so for a partition with just one record, it seeks to offset 0, which is exactly where the single record lives. The poll then retrieves that record, so the method returns the expected result.

Based on this, it looks like there isn’t an issue with single-record topics. Happy to share the test I ran if it’s helpful.