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Current state: Under Discussion
Discussion thread: here
JIRA: here
Motivation
Old users of Kafka that still use the original MirrorMaker need a path to migrate to MirrorMaker2. This involves implementing a new ReplicationPolicy and due to the differences between MirrorMaker1 and MirrorMaker2 its proposed to add a new method called canTrackSource to the public interface of ReplicationPolicy so that its possible to abstract over replication policies that can either can or cannot track back to the original source.
Note that there is already a PR that implements both the original motivation (IdentityReplicationPolicy) along with the adjustments to the interface at https://github.com/apache/kafka/pull/10648. The PR is currently passing all tests, only this KIP is required to proceed.
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