Avro2s (Avro to Scala) is an avro schema to scala case class converter. It generates case classes that extend Avro's Java types, such as SpecificRecordBase, SpecificFixed, GenericEnumSymbol, etc. This ensures compatibility with community tooling, including Confluent Schema Registry.

Avro2s is essentially a rewrite of avrohugger. The motivations for the rewrite include:

• Enhanced support for Union types
• Improved maintainability by removing the use of and dependency on treehugger, which is no longer actively maintained
• Ease of implementing Scala 3 code generation

• Supports Scala 3
  • Union types are supported without the need for shapeless
  • Currently, Enums are still generated as Java enums
• Supports Scala 2.13
• Compatibility with all Avro types
• SBT plugin

Add sbt-avro2s to your project/plugins.sbt

addSbtPlugin("io.psilicon" % "sbt-avro2s" % "0.22.0")

Add the task as a compilation dependency in your build.sbt:

Compile / sourceGenerators += (Compile / avro2sGenerate).taskValue

Now when you compile your project the sbt-avro2s plugin will attempt to generate case classes for all *.avdl and *.avsc under the src/main/avro directory.

This is only going to succeed if you also have avro in your dependencies. For example,

libraryDependencies ++= Seq(
  "org.apache.avro" % "avro" % "1.11.3"
)

Add avro2s to your build.sbt:

libraryDependencies += "io.psilicon" % "avro2s_2.13" % "0.3.0"

For Scala 2.13 generation. If you are using Union types, other than unions representing nullable (["null", T]), you will need to add shapeless to your build.sbt to run the generated code:

libraryDependencies += "com.chuusai" % "shapeless_2.13" % "2.3.10"

Example usage:

import avro2s.generator.CodeGenerator
import avro2s.language.ScalaVersion

object Demo extends App {
  
  CodeGenerator.generateCode(
    "input_directory",
    "output_directory",
    GeneratorConfig(ScalaVersion.Scala_2_13, logicalTypesEnabled = true)
  )
}  

• Scaladoc generation
• Scala 3 Enum support

• Thank you to everyone who contributed to avrohugger, upon which this code is based.
  • Parts of this code are directly copied from avrohugger; a lot of the code within the filesorter, parser and schema packages has been changed only slightly.
• ScalaPB, for inspiration on streamlining the code generation process, particularly for the FunctionalPrinter class.