make version non-optional

[mr-git]

No description provided.

[coveralls]

Pull Request Test Coverage Report for Build 11837553250

Details

• 7 of 10 (70.0%) changed or added relevant lines in 5 files are covered.
• 7 unchanged lines in 7 files lost coverage.
• Overall coverage increased (+0.2%) to 83.298%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
eventual-cassandra/src/main/scala/com/evolutiongaming/kafka/journal/eventual/cassandra/JournalStatements.scala	0	1	0.0%
replicator/src/main/scala/com/evolutiongaming/kafka/journal/replicator/ReplicateRecords.scala	2	4	50.0%

Files with Coverage Reduction	New Missed Lines	%
journal/src/main/scala/com/evolutiongaming/kafka/journal/eventual/ReplicatedPartitionJournal.scala	1	74.14%
replicator/src/main/scala/com/evolutiongaming/kafka/journal/replicator/ReplicateRecords.scala	1	84.48%
replicator/src/main/scala/com/evolutiongaming/kafka/journal/replicator/Batch.scala	1	97.83%
journal/src/main/scala/com/evolutiongaming/kafka/journal/HeadInfo.scala	1	81.08%
cassandra/src/main/scala/com/evolutiongaming/kafka/journal/eventual/cassandra/CassandraSession.scala	1	92.31%
core/src/main/scala/com/evolutiongaming/kafka/journal/Key.scala	1	81.82%
snapshot/src/main/scala/com/evolutiongaming/kafka/journal/BufferNr.scala	1	88.89%

Totals
Change from base Build 11741973464:	0.2%
Covered Lines:	3167
Relevant Lines:	3802

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💛 - Coveralls

[mr-git]

Technically, we do not need here and in 3 other places the default value, right?

All clients with versions since 0.0.152 have to provide these in payload over Kafka. Oldest client we have is 0.0.177, IIRC, thus all of them must provide version field, right?

I checked the history for those journal/src/test/resources/com/evolutiongaming/kafka/journal and related unit-tests - they are more than 6 years old, they were introduced in version 0.0.10 - I am leaning on upgrading them to state/format, which is expected at 0.0.177 - then we will require these fallbacks

Other option would be to introduce protocol version, but that could be overkill at this moment

[dfakhritdinov]

This PR contains braking changes in public API (including some case classes). I see no nice & simple option to overcome this by making desired change backward compatible and propose postponing the PR til next major version bump.

cc @mr-git