v2.16.0

New experimental features

• Serializers and deserializers can now be supplied to a producer, dependent
  producer or consumer as a builder, which the client invokes during its own
  construction and then owns, disposing it (and any Schema Registry client it
  created) when the client itself is disposed. See the AvroGeneric example (#2661)
• Schema Registry serde builders are now available for each supported format,
  each configurable with a Schema Registry client you own or the
  configuration to build one from. See the AvroGeneric,
  JsonSerialization and Protobuf examples (#2661)
• Producers, consumers and admin clients can now report the id of the Kafka
  cluster they're connected to (#2661)
• The Kafka cluster id is now propagated to Schema Registry serializers and
  deserializers automatically, and resolved lazily on first use, so subject
  name strategies based on the cluster no longer need it configured by hand.
  See the AvroGenericAssociation example (#2661)
• The serializer and deserializer builder APIs (Set*SerializerBuilder and
  Set*DeserializerBuilder on the producer and consumer builders, the Schema
  Registry serde builders), IClusterIdAware, ISerdeDisposable, SerdeExtensions
  and the ClusterId client extension are experimental: they are subject to
  change or removal in a future release (#2661)

Enhancements

• References librdkafka.redist 2.16.0. Refer to the librdkafka v2.16.0 release notes for more information
• Add support for saving Azure key version with DEK (#2641)
• Pass context when clients make KEK calls to DEK Registry (#2642)
• Add support for inline validation rules (#2651)
• Add Variant, Decimal, and Timestamp CEL functions (#2653)
• Add support for linux-s390x (IBM Z), with CI coverage on s390x (#2646)
• Add support for AliCloud KMS provider with CSFLE/CSPE (#2648)
• Schema Registry examples now use the serde builder API (#2661)

Fixes

• Fix the CSFLE ciphertext version field being written little-endian on big-endian
  platforms, which made encrypted fields unreadable across architectures
• Fix message Timestamp.Type being read as NotAvailable on big-endian platforms
  (e.g. s390x): librdkafka's rd_kafka_timestamp_type_t out-parameter (a 32-bit enum)
  was marshalled as a pointer-sized IntPtr, so the value landed in the high word and
  was truncated to 0 on big-endian

v2.15.1

Enhancements

• References librdkafka.redist 2.15.1. Refer to the librdkafka v2.15.1 release notes for more information.

Fixes

• Fix early return in FindMessageByName (#2644)
• Preserve HTTP status for retriable SR errors (#2647)
• Security patch in examples and tests using old NJsonSchema versions, test framework upgrade in Confluent.Kafka tests (#2656)

v2.15.0

Upgrade considerations

Ensure you're not calling StoreOffset with an EOF message.
As when calling Commit with an EOF message, it will throw an InvalidOperationException.
Previously this could cause skipping an offset (<2.1.0) or message reprocessing (>=2.1.0).

New features

• New optional package Confluent.Kafka.OAuthBearer.Aws provides AWS IAM-based
  OAUTHBEARER authentication via AWS STS GetWebIdentityToken. Activate by
  setting SaslOauthbearerMethod = SaslOauthbearerMethod.Oidc,
  SaslOauthbearerMetadataAuthenticationType.AwsIam, and supplying
  region and audience in SaslOauthbearerConfig. See the package's README
  for details.

Enhancements

• References librdkafka.redist 2.15.0. Refer to the librdkafka v2.15.0 release notes for more information.
• Added support for .NET 10 (LTS) and dropped support for .NET 6 (end of support since November 2024). The library now multi-targets net8.0 and net10.0 alongside netstandard2.0 and net462. Builds on the approach proposed in #2545 by Fernando Luiz de Lima (@ffernandolima), adapted for the centralized Directory.Build.props structure on current master.
• Adds support for union-of-pools/ auto pool mapping for Schema Registry (#2634)

Fixes

• Throw an InvalidOperationException when calling StoreOffset with an EOF consume result, to match Commit behavior (#2621)
• Handle non-http errors during retries (#2633)

v2.14.2

Enhancements

• References librdkafka.redist 2.14.2. Refer to the librdkafka v2.14.2 release notes for more information.
• Add IHeader overload to Headers.Add() method (#2604)

Fixes

• Handle anyOf/allOf in JSON transforms (#2611)
• Allow encrypting enum for JObject in dotnet (#2615)
• Fix 'occured' -> 'occurred' typo in ConsumeException XML doc comments (#2609)

v2.14.0

Enhancements

• References librdkafka.redist 2.14.0. Refer to the librdkafka v2.14.0 release notes for more information.
• Add AssociatedNameStrategy (#2577)
• Add enableAt to RuleSet (#2593)
• Add config to validate before domain rules for JSON Schema (#2596)
• Cache FieldAccessor to address CSFLE perf with JSON (#2601)

Fixes

• Ensure dispose methods clean up properly (#2595)

v2.13.2

Enhancements

• Preserve inner exceptions in RestService (#2571)

Fixes

• Support multi-certificate PEM bundles in Schema Registry SslCaLocation (#2576)

v2.13.1

Enhancements

• Unify build configurations and remove redundant properties (#2464)
• JSONSchema Validation Errors: Include paths to nested properties (#2554)
• Add Confluent-Client-Version header to requests to SR, C# client (#2549)

Fixes

• Fix DeriveKey in Hkdf implementation (#2559)
• Ensure single use of HttpRequestMessage for token fetch (#2544)
• Fix race conditions when retrieving KEK/DEK (#2565)
• Allowing for Confluent-Identity-Pool-Id to be optional (#2564)
• Ensure JSON schema access is thread-safe (#2567)
• Use lock on root schema when protecting access to subschemas (#2568)
• Processing arrays and maps sequentially to avoid race conditions (#2569)

v2.13.0

Enhancements

• References librdkafka.redist 2.13.0. Refer to the librdkafka v2.13.0 release notes for more information.
• Support Avro schema references for C# client (#2534)
• Add Accept-Version header (#2536)
• Handle evolution during field transformation (#2541)
• Re-enable deserialization optimization by removing unnecessary array conversions (#2531)

Fixes

• Ensure schemaId initialization is thread-safe (#2540)
• Ensure all deps are strongly named (#2548)

v2.12.0

KIP-848 – General Availability

Starting with Confluent.Kafka 2.12.0, the next generation consumer group rebalance protocol defined in KIP-848 is production-ready. Please refer to the following migration guide for moving from Classic to Consumer protocol.

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. GroupProtocol configuration property dictates whether to use the new Consumer protocol or older Classic protocol. It defaults to Classic if not provided.

Enhancements

• References librdkafka.redist 2.12.0. Refer to the librdkafka v2.12.0 release notes for more information.
• OAuth OIDC method example for Kafka metadata based authentication with
  an Azure IMDS endpoint using an attached managed identity as principal (#2526).

v2.11.1

Enhancements

• References librdkafka.redist 2.11.1. Refer to the librdkafka v2.11.1 release notes for more information.