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The deprecated policy interfaces and configuration keys will be removed in a future Kafka version. If this KIP is accepted for Kafka 1.1.0 this removal could happen in Kafka 2.0.0 or a later major release.

This KIP proposes to retrospectively apply policies to two APIs (delete topics and delete records) exposed via the network protocol. Existing clients might not be expecting a POLICY_VIOLATION error code in the responses. To mitigate this, only the new version of these network protocols will actually return POLICY_VIOLATION. If a client is using an old version of either of these protocols, the policy violation will be returned an UNEXPECTED_SERVER_ERROR, and a message logged to explain that the error is in fact a policy violation.

Rejected Alternatives

The objectives of this KIP could be achieved without deprecating the existing policy classes, but that:

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