Note: The new consumer group protocol defined in KIP-848 is not enabled by default. There are few contract change associated with the new protocol and might cause breaking changes. group.protocol configuration property dictates whether to use the new consumer protocol or older classic protocol. It defaults to classic if not provided.

Enhancements and Fixes

• Support for OAUTHBEARER metadata based authentication types, starting with Azure IMDS. Introduction available (#5155).
• Fix compression types read issue in GetTelemetrySubscriptions response for big-endian architectures (#5183, @paravoid).
• Fix for KIP-1102 time based re-bootstrap condition (#5177).
• Fix for discarding the member epoch in a consumer group heartbeat response when leaving with an inflight HB (#4672).
• Fix for an error being raised after a commit due to an existing error in the topic partition (#4672).
• Fix double free of headers in rd_kafka_produceva method (@blindspotbounty, #4628).
• Fix to ensure rd_kafka_query_watermark_offsets enforces the specified timeout and does not continue beyond timeout expiry (#5201).
• New walkthrough in the Wiki about configuring Kafka cross-realm authentication between Windows SSPI and MIT Kerberos.

Fixes

General fixes

• Issues: #5178. Fix for KIP-1102 time based re-bootstrap condition. Re-bootstrap is now triggered only after metadata.recovery.rebootstrap.trigger.ms have passed since first metadata refresh request after last successful metadata response. The calculation was since last successful metadata response so it's possible it did overlap with the periodic topic.metadata.refresh.interval.ms and cause a re-bootstrap even if not needed. Happening since 2.11.0 (#5177).
• Issues: #4878. Fix to ensure rd_kafka_query_watermark_offsets enforces the specified timeout and does not continue beyond timeout expiry. Happening since 2.3.0 (#5201).

Telemetry fixes

• Issues: #5179 . Fix issue in GetTelemetrySubscriptions with big-endian architectures where wrong values are read as accepted compression types causing the metrics to be sent uncompressed. Happening since 2.5.0. Since 2.10.1 unit tests are failing when run on big-endian architectures (#5183, @paravoid).

Consumer fixes

• Issues: #5199 Fixed an issue where topic partition errors were not cleared after a successful commit. Previously, a partition could retain a stale error state even though the most recent commit succeeded, causing misleading error reporting. Now, successful commits correctly clear the error state for the affected partitions Happening since 2.4.0 (#4672).

Producer fixes

• Issues: #4627. Fix double free of headers in rd_kafka_produceva method in cases where the partition doesn't exist. Happening since 1.x (@blindspotbounty, #4628).

Checksums

Release asset checksums:

• v2.12.0.zip SHA256 9b2f373e03f3d5d87c2075b3ce07ee9ea3802eea00cea41b99d8351a68d8a062
• v2.12.0.tar.gz SHA256 1355d81091d13643aed140ba0fe62437c02d9434b44e90975aaefab84c2bf237