j5ik2o

case class UserAcount(id: Long, name: String, groupId: Long) {
  
  // ...
  
  def groupName(groupRepository: GroupRepository): Task[GroupName] = groupRepository.resolveBy(groupId).map(_.name)
  
}

j5ik2o

package domain

trait Money {
  
  def plus(other: Money): Money
  
  def minus(other: Money): Money
  
  // ...
}

j5ik2o

型パラメータが高階型の場合のDIについて

トレイト: UserAccountRepository[M[_]] https://github.com/j5ik2o/scala-ddd-base/blob/master/example/src/main/scala/com/github/j5ik2o/dddbase/example/repository/UserAccountRepository.scala

実装: UserAccountRepositoryBySkinny https://github.com/j5ik2o/scala-ddd-base/blob/master/example/src/main/scala/com/github/j5ik2o/dddbase/example/repository/skinny/UserAccountRepositoryBySkinny.scala

があったとして、以下のようなDIをさせたいのですが、

j5ik2o

class ApiServer extends HttpApp {

  protected val design: Design = bind[Design] // ApiServerの外部で定義されているDesginを参照したい
    .bind[AtomicReference[ActorSystem]]
    .toInstance(systemReference)
    .bind[ActorSystem]
    .toInstanceProvider[AtomicReference[ActorSystem]](_.get)
  
  // snip
  

j5ik2o

package point

import akka.actor.{Actor, ActorRef, ActorSystem, Props}
import point.MainActor.Start
import point.Point.{Distance, DistanceResult}

import scala.concurrent.Await
import scala.concurrent.duration._

object MainActor {

j5ik2o

case class Room(id: Long, members: Seq[Member]) 
// このロジックはRoomが持つべき振る舞いだった場合（ドメインロジックがドメインオブジェクトの外側にある状態)
room.copy(members = room.members :+ newMember)

// ほんとは、こうしたらよいのでは
case class Room(id: Long, members: Seq[Member]) {
  def addMember(value: Member): Room = 
    copy(members = this.members :+ value)
}
room.addMember(newMember)

j5ik2o

package app

import cats.free._
import cats._

class DDD[ID, E] {

  def resolveBy(id: ID): Free[RepositoryDSL, Option[E]] = Free.liftF(ResolveBy(id))

  def store(id: ID, entity: E): Free[RepositoryDSL, Unit] = Free.liftF(Store(id, entity))

j5ik2o

package example

/**
  * 値が存在する・しないの両状態を表す型を表すトレイト。
  *
  * @tparam A 値の型
  */
sealed trait MyOption[+A] {

  /**

j5ik2o

import java.io._
import java.nio.charset.StandardCharsets

object LoarnMain extends App {

  def getFileBody(file: String): String =
    using(new FileInputStream(file)) { fis =>
      val text = new Array[Byte](fis.available)
      fis.read(text)
      new String(text, StandardCharsets.UTF_8)

j5ik2o

style = defaultWithAlign # For pretty alignment.
maxColumn = 100          # For my wide 30" display.
includeCurlyBraceInSelectChains = false
newlines.penalizeSingleSelectMultiArgList = false
project.git = true
project.excludeFilters = ["target/"]