robhinds

trait DocumentRoute[F[_]] extends DocumentRepository[F]{
  def F: Monad[F]

  val getDocuments: Route = (get & path("documents")) { 
      complete(
        documents()
      )
  }

robhinds

trait S3DocumentRepository[Future] {
  def documents:Future[Seq[Document]] = ???
}

robhinds

trait DocumentRepository[F[_]] {
  def documents: F[Seq[Document]]
}

robhinds

object idInterpreter extends (IndexAlg ~> Id) {
 override def apply[A](fa: IndexAlg[A]): Id[A] = fa match {
   case CreateIndex(_) => ().asRight[String]
   case DeleteIndex(_) => ().asRight[String]
 }
}

robhinds

def recreateIndex(name: String): IndexDSL[Either[String, CreateIndexResponse]] = 
  for { 
    _ <- deleteIndex(name) 
    created <- createIndex(name) 
  } yield created

robhinds

type IndexDSL[A] = Free[IndexAlg, A] 
def createIndex(name: String): IndexDSL[Either[String, CreateIndexResponse]] = Free.liftF(CreateIndex(name)) 
def deleteIndex(name: String): IndexDSL[Either[String, DeleteIndexResponse]] = Free.liftF(DeleteIndex(name))

robhinds

def recreateIndex(name: String) = 
  for { 
    _ <- deleteIndex(name) 
    created <- createIndex(name) 
  } yield created

robhinds

val sequentialFuture = for {
 x <- Future { Thread sleep 1000; 10 }
 y <- Future { Thread sleep 2000; 32 }
} yield x + y

robhinds

sealed trait IndexAlg[A] 
case class CreateIndex(name: String) extends IndexAlg[Either[String, CreateIndexResponse]] 
case class DeleteIndex(name: String) extends IndexAlg[Either[String, DeleteIndexResponse]]

robhinds

import cats.{Id, Monad}
import cats.data.EitherT
import cats.implicits._
import cats.syntax.functor._
import cats.syntax.flatMap._

import scala.concurrent.Future
import scala.concurrent.ExecutionContext.Implicits.global