pizza_transformation.scala

/*
<build.sbt>
scalaVersion := "2.13.0"
libraryDependencies ++= Seq(
  "com.sksamuel.avro4s" %% "avro4s-core" % "3.0.1",
  "eu.timepit" %% "refined" % "0.9.9",
  "io.scalaland" %% "chimney" % "0.3.2"
)

<plugins.sbt>
addSbtPlugin("com.julianpeeters" % "sbt-avrohugger" % "2.0.0-RC19")
*/
package test01

import test.avro4s.{json => avro}
import eu.timepit.refined.api.Refined
import eu.timepit.refined.collection.NonEmpty
import eu.timepit.refined.refineMV
import io.scalaland.chimney.dsl._
import io.scalaland.chimney.Transformer

object Main01 {
  case class Amount(value: Double) extends AnyVal

  type Name = String Refined NonEmpty

  sealed trait VegetarianType
  object VegetarianType {
    case object None       extends VegetarianType
    case object Vegetarian extends VegetarianType
    case object Vegan      extends VegetarianType
  }

  case class Ingredient(
    name:  Name,
    sugar: Amount,
    fat:   Amount
  )
  case class Pizza(
    name:           Name,
    ingredients:    List[Ingredient],
    calories:       Int,
    vegetarianType: VegetarianType = VegetarianType.None
  )

  val domainPizza = Pizza(
    name        = refineMV("pepperoni"),
    ingredients = List(//| name        | sugar     | fat
      Ingredient(refineMV("pepperoni"), Amount(12), Amount(4.4)),
      Ingredient(refineMV("onions"),    Amount(1),  Amount(0.4))
    ),
    calories    = 98
  )

  val avroPizza1 = avro.Pizza(
    name        = domainPizza.name.value,
    ingredients = domainPizza.ingredients.map { i =>
      avro.Ingredient(
        name  = i.name.value,
        sugar = i.sugar.value,
        fat   = i.fat.value)
    },
    calories   = domainPizza.calories,
    vegetarian = domainPizza.vegetarianType != VegetarianType.None,
    vegan      = domainPizza.vegetarianType == VegetarianType.Vegan
  )

  implicit val nameToString: Transformer[Name, String] = _.value

  val avroPizza2 = domainPizza.into[avro.Pizza]
    .withFieldComputed(_.vegetarian, _.vegetarianType != VegetarianType.None)
    .withFieldComputed(_.vegan,      _.vegetarianType == VegetarianType.Vegan)
    .transform

  def main(args: Array[String]): Unit = {
    println(avroPizza1)
    println(avroPizza2)
  }
}