Xiaobing Fang created KAFKA-15136: ------------------------------------- Summary: The inspection of field allowAutoTopicCreation field in MetadataRequest is unreasonable Key: KAFKA-15136 URL: https://issues.apache.org/jira/browse/KAFKA-15136 Project: Kafka Issue Type: Improvement Components: clients Reporter: Xiaobing Fang
```java if (!data.allowAutoTopicCreation() && version < 4) throw new UnsupportedVersionException("MetadataRequest versions older than 4 don't support the " + "allowAutoTopicCreation field"); ``` Background: Based on my understanding, the code in MetadataRequest is intended to ignore the allowAutoTopicCreation field when version≤4. However, if kafka server is configured with "auto.create.topics.enable"=false and the client sets allowAutoTopicCreation=false, UnsupportedVersionExceptionwill be thrown, which is not expected. Issues: # `KafkaAdminClient#handleDescribeTopicsByNames()` throws an exception when sending MetadataRequest to a lower version server, making it unusable. # MetadataRequestTest avoids this issue by setting `allowAutoTopicCreation=true` in tests for version≤4, but this is not reasonable. And the comments in [testAutoTopicCreation|https://github.com/apache/kafka/blob/1f4cbc5d53259031123b6e9e6bb9a5bbe1e084e8/core/src/test/scala/unit/kafka/server/MetadataRequestTest.scala#L146] may also be problematic. Solution: # Remove the checking code in MetadataRequest. # Add a field `hasSetAllowAutoTopicCreation` in MetadataRequest. Only throw an exception when `version≤4` and `hasSetAllowAutoTopicCreation=true`, without considering the value of allowAutoTopicCreation field. If there is indeed an issue, I can work on fixing it. Looking forward to your reply. -- This message was sent by Atlassian Jira (v8.20.10#820010)