vvcephei commented on a change in pull request #9836: URL: https://github.com/apache/kafka/pull/9836#discussion_r561985705
########## File path: clients/src/main/java/org/apache/kafka/clients/consumer/internals/Fetcher.java ########## @@ -637,20 +636,32 @@ private ListOffsetResult fetchOffsetsByTimes(Map<TopicPartition, Long> timestamp } else { List<ConsumerRecord<K, V>> records = fetchRecords(nextInLineFetch, recordsRemaining); - if (!records.isEmpty()) { - TopicPartition partition = nextInLineFetch.partition; - List<ConsumerRecord<K, V>> currentRecords = fetched.get(partition); - if (currentRecords == null) { - fetched.put(partition, records); - } else { - // this case shouldn't usually happen because we only send one fetch at a time per partition, - // but it might conceivably happen in some rare cases (such as partition leader changes). - // we have to copy to a new list because the old one may be immutable - List<ConsumerRecord<K, V>> newRecords = new ArrayList<>(records.size() + currentRecords.size()); - newRecords.addAll(currentRecords); - newRecords.addAll(records); - fetched.put(partition, newRecords); + TopicPartition partition = nextInLineFetch.partition; + + if (subscriptions.isAssigned(partition)) { + // initializeCompletedFetch, above, has already persisted the metadata from the fetch in the + // SubscriptionState, so we can just read it out, which in particular lets us re-use the logic + // for determining the end offset + final long receivedTimestamp = nextInLineFetch.receivedTimestamp; + final Long beginningOffset = subscriptions.logStartOffset(partition); + final Long endOffset = subscriptions.logEndOffset(partition, isolationLevel); + final FetchPosition fetchPosition = subscriptions.position(partition); + + final FetchedRecords.FetchMetadata fetchMetadata = fetched.metadata().get(partition); + if (fetchMetadata == null + || !fetchMetadata.position().offsetEpoch.isPresent() + || fetchPosition.offsetEpoch.isPresent() + && fetchMetadata.position().offsetEpoch.get() <= fetchPosition.offsetEpoch.get()) { Review comment: Ah, good catch. It looks like this was also leftover from a previous version. I used to directly populate the returned metadata from the fetch response, but now I'm just populating the returned metadata from the subscription state, which `initializeCompletedFetch` has already updated. The benefit is that we don't have to worry about cases like this, since they've already been checked. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org