Status

Current state: "Under Discussion"

Discussion thread: here

JIRA:  Unable to render Jira issues macro, execution error.

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

Motivation

Currently when a user sends a null key to a log compacted topic, the broker returns CorruptRecordException, which is a retriable exception. As such, the producer keeps retrying until retries are exhausted or request.timeout.ms expires and eventually throws a TimeoutException. This is confusing and not user-friendly. 

The broker should throw a non-retriable exception with a message explaining the error.

New or Changed Public Interfaces

This KIP introduces a new error type INVALID_KEY.

It introduces a new non-retriable exception InvalidKeyException. Going forward user request will fail without doing retries, if they try to produce to a log compacted topic with a null key.

Proposed Changes

Add a new error code and exception as follows :

Error Code :

INVALID_KEY(45, new InvalidKeyException("Message key is invalid."))

Exception :

public class InvalidKeyException extends ApiException {
    
private static final long serialVersionUID = 1L;

    public InvalidKeyException() {
        super();
    }

    public InvalidKeyException(String message, Throwable cause) {
        super(message, cause);
    }

    public InvalidKeyException(String message) {
        super(message);
    }

    public InvalidKeyException(Throwable cause) {
        super(cause);
    }
}

Compatibility, Deprecation, and Migration Plan

We will only return this exception for ProduceRequest V3 or higher. The older version of ProduceRequest will still get the CorruptRecordException.

Rejected Alternatives