[KAFKA-5030] Suggested clean-ups from message format V2 review

• Type: Sub-task
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: clients, core, producer
• Labels: exactly-once
• Assignee: Unassigned
• Reporter: Ismael Juma
• Created: 06/Apr/17 09:30
• Updated: 17/Feb/19 19:11

Description

A few random clean-ups raised during the review of the message format V2 PR:

1. We should use magic or message format version consistently. It seems like we are moving towards the former.
2. We should consider moving Log.analyzeAndValidateRecords to LogValidator so that the validation logic is all in the same class.
3. MemoryRecords.toString should include batch information, it currently only includes records information.
4. Record.hasMagic should be hasCompatibleMagic to make the behaviour clearer. For version 2, it returns true if the passed magic is greater than or equal to 2.
5. Once we move to Java 8, move AbstractRecordBatch's methods to RecordBatch (i.e. default methods) and remove AbstractRecordBatch.
6. Consider moving some of the down-conversion logic from KafkaApis to FetchRequest so that it can be more easily unit testable.