avro4s-kafka-schema-registry

Kafka Serializer, Deserializer, and Serde implementations for Avro-encoded messages, backed by avro4s for schema derivation and the Confluent Schema Registry for schema management.

Features

• Derives Avro schemas automatically from Scala case classes via avro4s
• Encodes/decodes messages using the Confluent wire format (magic byte + schema ID + Avro binary payload)
• Supports optional auto-registration of schemas in the registry
• Cross-built for Scala 2.12, 2.13, and 3

Usage

import com.lvitaly.avro4s.kafka.schema.registry.serde.Avro4sSerde
import io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient

case class MyEvent(id: String, value: Int)

val schemaRegistry = new CachedSchemaRegistryClient("http://localhost:8081", 100)

// Create a Serde for use with Kafka Streams or the Kafka consumer/producer API
val serde = Avro4sSerde[MyEvent](
  schemaRegistry,
  isKey = false,            // true for key serdes
  autoRegisterSchema = true // set to false to require pre-registered schemas
)

You can also use Avro4sSerializer and Avro4sDeserializer directly if you only need one direction.

Building

This project uses Mill.

./mill avro4s-kafka-schema-registry[2.13.18].compile

Dependencies

The Confluent Maven repository is required:

https://packages.confluent.io/maven/

License

This project is open source. See the repository for license details.