timeouts.scala

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.duration._
import cats.effect.{IO, Timer}
import cats._
import cats.implicits._

object X extends App {

  def recoverTimeout[A](fa: IO[A], after: FiniteDuration, fallback: A)
                  (implicit timer: Timer[IO]): IO[A] = {

    IO.race(fa.recover { case _ => fallback}, timer.sleep(after)).flatMap {
      case Left(a) => IO.pure(a)
      case Right(_) => IO.pure(fallback)
    }
  }

  def call1 = { println("starting call1"); Thread.sleep(1000);println("finished call1");  1}
  def call2 = { println("starting call2"); Thread.sleep(2000);println("finished call2");  2}
  def call3 = { throw new Exception("boom")}

  println("Starting")

  private val duration: FiniteDuration = 1.5 second // try 0.5, 2.5

   val l  = (
      recoverTimeout(IO.shift *> IO { call1 }, duration, 11),
      recoverTimeout(IO.shift *> IO { call2 }, duration, 12),
      recoverTimeout(IO.shift *> IO { call3 }, duration, 13)
   ).parMapN( (x,y,z) => (x,y,z))

  val result = l.unsafeRunSync()

  println(s"Finished $result")

}