1.发布时间

KIP Freeze时间：2019年9月25日

Feature Freeze时间：2019年10月4日

Code Freeze时间：2019年10月16日

Release时间：2019年12月16日

2.版本需求

Kafka2.4.0版本对以下37个特性进行了开发。

KIP-213: Support non-key joining in KTable

KIP-307: Allow to define custom processor names with KStreams DSL

KIP-309: Add toUpperCase support to sasl.kerberos.principal.to.local rule

KIP-369: Alternative Partitioner to Support "Always Round-Robin" Selection

KIP-379: Multiple Consumer Group Management

KIP-382: MirrorMaker 2.0

KIP-392: Allow consumers to fetch from closest replica

KIP-412: Extend Admin API to support dynamic application log levels

KIP-429: Kafka Consumer Incremental Rebalance Protocol (Partially implemented)

KIP-434: Add Replica Fetcher and Log Cleaner Count Metrics

KIP-440: Extend Connect Converter to support headers

KIP-444: Augment metrics for Kafka Stream (Partially Implemented)

KIP-455: Admin API for Replica Reassignment (Partially implemented)

KIP-460: Admin Leader Election RPC

KIP-464: Defaults for AdminClient#createTopic

KIP-467: Augment ProduceResponse error messaging for specific culprit records (Partially implemented)

KIP-470: TopologyTestDriver test input and output usability improvements

KIP-471: Expose RocksDB Metrics in Kafka Streams (Partially Implemented)

KIP-474: To deprecate WindowStore#put(key, value)

KIP-475: New Metrics to Measure Number of Tasks on a Connector

KIP-479: Add StreamJoined config object to Join

KIP-480: Sticky Partitioner

KIP-481: SerDe Improvements for Connect Decimal type in JSON

KIP-482: The Kafka Protocol should Support Optional Fields

KIP-484: Expose metrics for group and transaction metadata loading duration

KIP-488: Clean up Sum,Count,Total Metrics

KIP-492: Add java security providers in Kafka Security config

KIP-495: Dynamically Adjust Log Levels in Connect

KIP-496: Administrative API to delete consumer offsets

KIP-503: Add metric for number of topics marked for deletion

KIP-504: Add new Java Authorizer Interface

KIP-525: Return topic metadata and configs in CreateTopics response

KIP-507: Securing Internal Connect REST Endpoints

KIP-511: Collect and Expose Client's Name and Version in the Brokers (Partially implemented)

KIP-517: Add consumer metrics to observe user poll behavior

KIP-521: Enable redirection of Connect's log4j messages to a file by default

KIP-528: Deprecate PartitionGrouper configuration and interface