Hi chia, chia_13: `ConsumerGroupDescription` now gains a new method `groupCreationTimeMs()`:
`groupCreationTimeMs()` (`Optional<Long>`): the epoch-ms when this consumer group was first created on the broker. `Optional.empty()` if unknown. Please take a look at the updated KIP and let us know if you have further questions. Best Regards, Jiunn-Yang > Chia-Ping Tsai <[email protected]> 於 2026年4月2日 上午9:58 寫道： > > hi Jiunn > > chia_13: should we update the public API: ConsumerGroupDescription as well? > > Best, > Chia-Ping > > On 2026/04/01 11:59:46 黃竣陽 wrote: >> Hi chia, >> >> Thank you for the thoughtful feedback! >> >> chia_10: I have added a clarification in the Proposed Changes section to >> address this. In this case, >> ListOffsetsRequest will resolve to the Log End Offset, but this is not a >> fallback to `latest`. The distinction >> matters: `latest` is a direct seek to the Log End Offset, whereas >> `by_start_time` always anchors to the >> group creation timestamp and lets the lookup result follow naturally. The >> consumer will begin consuming >> any new records produced after this point normally. >> >> chia_11: I have introduced a new exception >> `GroupCreationTimeUnknownException` to signal >> this specific condition. >> >> chia_12: I have updated the KIP to expose the group creation timestamp via >> `AdminClient.describeConsumerGroups()` >> , accessible through `ConsumerGroupDescription.groupCreationTimeMs()`. This >> is backed by a new >> `GroupCreationTimeMs` field in `ConsumerGroupDescribeResponse. >> >> Best Regards, >> Jiunn-Yang >> >>> Chia-Ping Tsai <[email protected]> 於 2026年4月1日 下午2:33 寫道： >>> >>> hi Jiunn >>> >>> thanks for updating KIP. I have a couple of questions. >>> >>> chia_10: What happen if the group creation time is strictly greater than >>> the timestamp of the latest record in the partition? Will the consumer fall >>> back to the "latest" offset behaviour in this case? It could be good to >>> elucidate that in the KIP >>> >>> chia_11: Could you specify which exact exception will be thrown when the >>> group creation time is unknown >>> >>> chia_12: Since the group creation time is now a critical semantic anchor, >>> should we also expose it via the `DescribeGroupsResponse`? >>> >>> Best, >>> Chia-Ping >>> >>> On 2026/03/05 11:14:31 黃竣陽 wrote: >>>> Hello everyone, >>>> >>>> I would like to start a discussion on KIP-1282: Prevent data loss during >>>> partition expansion for dynamically added partitions >>>> <https://cwiki.apache.org/confluence/x/mIY8G> >>>> >>>> This proposal aims to introduce a new auto.offset.reset policy >>>> by_start_time, anchoring the >>>> offset reset to the consumer's startup timestamp rather than partition >>>> discovery time, to prevent >>>> silent data loss during partition expansion. >>>> >>>> Best regards, >>>> Jiunn-Yang >> >>
