chimney

Author: baovitt

build.sbt

@@ -445,6 +445,7 @@ lazy val scala_libraries = (project in file("scala-libraries"))
       "org.elasticmq" %% "elasticmq-rest-sqs" % "1.6.7",
       "software.amazon.awssdk" % "sqs" % "2.27.10"
     ),
+    libraryDependencies += "io.scalaland" %% "chimney" % "1.4.0",
     Defaults.itSettings
   )
 

scala-libraries/src/main/scala/com/baeldung/chimney/Codec.scala

@@ -0,0 +1,10 @@
+package com.baeldung.chimney
+
+import io.scalaland.chimney.*, dsl.*, partial.*
+
+object ChimneyCodec extends App:
+
+  case class Domain(a: Int, b: String)
+  case class Dto(b: Option[String], a: Option[Int])
+
+  given Codec[Domain, Dto] = Codec.derive

scala-libraries/src/main/scala/com/baeldung/chimney/Iso.scala

@@ -0,0 +1,10 @@
+package com.baeldung.chimney
+
+import io.scalaland.chimney.*, dsl.*, partial.*
+
+object ChimneyIso extends App:
+
+  case class StructuredItem(uuid: java.util.UUID)
+  case class DomainItem(uuid: java.util.UUID)
+
+  given Iso[StructuredItem, DomainItem] = Iso.derive

scala-libraries/src/main/scala/com/baeldung/chimney/PartialTransformer.scala

@@ -0,0 +1,15 @@
+package com.baeldung.chimney
+
+import io.scalaland.chimney.*, dsl.*, partial.*
+
+object ChimneyPartialTransformer extends App:
+
+  val fn: Int => Boolean =
+    case 0 => false
+    case 1 => true
+    case i => throw Exception(s"Provided integer invalid: $i")
+
+  given PartialTransformer[Int, Boolean] =
+    PartialTransformer.fromFunction(fn)
+
+  val result: Result[Boolean] = 0.transformIntoPartial[Boolean]

scala-libraries/src/main/scala/com/baeldung/chimney/Patcher.scala

@@ -0,0 +1,22 @@
+package com.baeldung.chimney
+
+import io.scalaland.chimney.dsl.*
+
+object ChimneyPatcher extends App:
+
+  case class User(id: Int, email: Option[String], phone: Option[Long])
+
+  case class UserUpdateForm(email: String, phone: Long)
+
+  val user = User(10, Some("abc@@domain.com"), Some(1234567890L))
+  val updateForm = UserUpdateForm("xyz@@domain.com", 123123123L)
+
+  val patchedValue: User = user.patchUsing(updateForm)
+
+  // Standard Library Alternative
+
+  case class SimpleCaseClass(a: Int, b: Int)
+
+  val simpleClass = SimpleCaseClass(0, 0)
+
+  simpleClass.copy(b = 2) // SimpleCaseClass(0, 2)

scala-libraries/src/main/scala/com/baeldung/chimney/Transformer.scala

@@ -0,0 +1,106 @@
+package com.baeldung.chimney
+
+import io.scalaland.chimney.*, dsl.*, partial.*
+
+object ChimneyTransformers extends App:
+
+  class MyType(val a: Int)
+
+  class MyOtherType(val b: String):
+    override def toString: String = s"MyOtherType($b)"
+
+  val transformer: Transformer[MyType, MyOtherType] = (src: MyType) =>
+    new MyOtherType(src.a.toString)
+
+  transformer.transform(new MyType(10)) // new MyOtherType("10")
+
+  implicit val transformerAsImplicit: Transformer[MyType, MyOtherType] =
+    transformer
+
+  (new MyType(10)).transformInto[MyOtherType]
+
+  // Transitive Given Instances
+
+  trait Serial[T]:
+    def serial(v: T): String
+
+  given Serial[MyOtherType] with
+    def serial(v: MyOtherType): String = v.toString
+
+  given [F, T](using Serial[T], Transformer[F, T]): Serial[F] with
+    def serial(v: F): String =
+      summon[Serial[T]].serial:
+        summon[Transformer[F, T]].transform(v)
+
+  // Automatic Case Class Transformation
+
+  // UserDTO
+
+  case class UserDTO(
+    name: String, // 1. primitive
+    addresses: Seq[AddressDTO], // 2. Seq collection
+    recovery: Option[RecoveryMethodDTO] // 3. Option type
+  )
+
+  case class AddressDTO(street: String, city: String)
+
+  sealed trait RecoveryMethodDTO
+
+  object RecoveryMethodDTO:
+    case class Phone(value: PhoneDTO) extends RecoveryMethodDTO
+    case class Email(value: EmailDTO) extends RecoveryMethodDTO
+
+  case class PhoneDTO(number: String)
+  case class EmailDTO(email: String)
+
+  // User Domain Model
+
+  case class User(
+    name: Username,
+    addresses: List[Address],
+    recovery: RecoveryMethod
+  )
+
+  case class Username(name: String) extends AnyVal
+  case class Address(street: String, city: String)
+
+  enum RecoveryMethod:
+    case Phone(number: String)
+    case Email(email: String)
+
+  // we can do a transformation:
+
+  User(
+    Username("John"),
+    List(Address("Paper St", "Somewhere")),
+    RecoveryMethod.Email("[email protected]")
+  ).transformInto[UserDTO]
+
+  // Standard Library alternatives
+
+  // Selectable
+
+  class Record(elems: (String, Any)*) extends Selectable:
+    private val fields = elems.toMap
+    def selectDynamic(name: String): Any = fields(name)
+
+  type Person = Record {
+    val name: String
+    val age: Int
+  }
+
+  val person = Record(
+    "name" -> "Emma",
+    "age" -> 42
+  ).asInstanceOf[Person]
+
+  // Tuple Generics
+
+  case class Employee(name: String, number: Int, manager: Boolean)
+
+  val bob: Employee = Employee("Bob", 42, false)
+
+  val bobTuple: (String, Int, Boolean) = Tuple.fromProductTyped(bob)
+
+  val bobAgain: Employee =
+    summon[deriving.Mirror.Of[Employee]].fromProduct(bobTuple)