Topic data pagination usability

[dweber019]

IMHO the pagination usability of the topic data view is broken.

I have a topic with 45 events

But if I navigate to the topic data view I only see 2 events right away

I can see on the pager that there should be 45 in the right upper corner.

When I navigate to the next page I can still see only 2 events, these are two other events

I would expect to see akhq.topic-data.size=50 events according to https://akhq.io/docs/configuration/akhq.html#topic-data per page.

Expectation:

1. akhq.topic-data.size works, if available 50 events per page are displayed
2. Pagination has a not only a next page button but a previous button too

Addition:

• I think it would even make sense to have the same paging experience as on the topic list view.
• I just realised that if I configure akhq.ui-options.topic-data.sort=OLDEST the akhq.topic-data.size is at least respected but never the less as the default is NEWEST, it's no a confusing experience

Context:
From time to time I give some Kafka courses and this usability is always an issue for the participants.

[tchiotludo]

Hey,

It's totally impossible due to Kafka Api:

• Kafka give us a number of record based on start offset and end offset (what is displayed on pagination).
• But these number are only bound number of offset and there no way to know what happen inside these bounds.
• Kafka have internal process that could leave empty offset that you will never be able to pull
  • each transaction will add empty offset for the BEGIN and the END at least
  • each compacted topic will remove duplicate key (what seems to be your case on the screenshot with multiple null key)
• it's why I added a ≈ everywhere, Kafka don't allow any correct pagination

[dweber019]

The topic is not compacted.

Are there any other reasons for this implementation / limitation?
I'm asking because other tools are able to do this like Kafka UI and wondering if there is a good reason why not to change this. Maybe there is something I'm not aware of 😅

[tchiotludo]

in that case, the number of records should be nearly relevant I think, but still not exact (depending on your workload, for example, transactions, ...)

[dweber019]

Sorry maybe my request was a bit misleading. The number next to the paging button isn't the issue for me. An issue is that only 2 messages are displayed per page and that we aren't able to page back to the previous page.