kafka/server/src
Ismael Juma 87b37a4065
KAFKA-14552: Assume a baseline of 3.0 for server protocol versions (#18497)
Kafka 4.0 will remove support for zk mode and will require conversion to kraft
before upgrading to 4.0. The minimum kraft version is 3.0 (aka 3.0-IV1).

This provides an opportunity to remove exclusively server side protocols versions
that only exist to allow direct upgrades from versions older than 3.0 or that are
used only by zk mode.

Since KRaft became production ready in 3.3, we should consider setting the
baseline to 3.3. But that requires more discussion and it can be done via a
separate change (KAFKA-18601).

Protocol changes:
* Remove RequestHeader v0 (only used by ControlledShutdown v0)
* Remove WriteTxnMarkers v0
* Remove all versions of ControlledShutdown, LeaderAndIsr, StopReplica, UpdateMetadata

In order to remove all versions safely, extend generator to support setting
"versions" to "none". In this case, we no longer generate the `*Data` classes,
but we still reserve the id for the relevant protocol api (so it doesn't get
accidentally used for something else). The protocol documentation is correct
after these changes.

We kept a simplified version of `LeaderAndIsr{Request|Response}` because
it's used by many tests that are still relevant in kraft mode. Once
KAFKA-18486 is done, it may be possible to remove it (I left a comment on
the ticket). Similarly, KAFKA-18487 may make it possible to remove
the introduced `StopReplicaPartitionState` (left a comment on that ticket too).

There are a number of places that were adjusted to include an
`ApiKeys.hasValidVersion` check.

Reviewers: Chia-Ping Tsai <chia7712@gmail.com>
2025-01-20 13:51:44 -08:00
..
main/java/org/apache/kafka KAFKA-14552: Assume a baseline of 3.0 for server protocol versions (#18497) 2025-01-20 13:51:44 -08:00
test/java/org/apache/kafka KAFKA-14552: Assume a baseline of 3.0 for server protocol versions (#18497) 2025-01-20 13:51:44 -08:00