title: Cannot find an implicit ExecutionContext. You might pass spray scala
body: <p>I have this two erros:</p>
  
  <pre><code>Error:(39, 20) Cannot find an implicit ExecutionContext. You might pass
  an (implicit ec: ExecutionContext) parameter to your method
  or import scala.concurrent.ExecutionContext.Implicits.global.
      val pipeline = sendReceive
  
                 ^
  
  Error:(39, 20) not enough arguments for method sendReceive: (implicit refFactory: akka.actor.ActorRefFactory, implicit executionContext: scala.concurrent.ExecutionContext, implicit futureTimeout: akka.util.Timeout)spray.client.pipelining.SendReceive.
  Unspecified value parameter executionContext.
      val pipeline = sendReceive
                 ^
  </code></pre>
  
  <p>My Code is:  </p>
  
  <pre><code>import scala.util.{Success, Failure}
  import scala.concurrent.duration._
  import akka.actor.ActorSystem
  import akka.pattern.ask
  import akka.event.Logging
  import akka.io.IO
  import spray.can.Http
  import spray.client.pipelining._
  import spray.util._
  import argonaut._, Argonaut._
  
  object test {
  
  case class Elevation(location: Location, elevation: Double)
  
  case class Location(lat: Double, lng: Double)
  
  case class GoogleApiResult(status: String, results: List[Elevation])
  
  implicit def locationFormat: CodecJson[Location] =    casecodec2(Location.apply, Location.unapply)("lat", "lng")
  
  implicit def elevationFormat: CodecJson[Elevation] = casecodec2(Elevation.apply, Elevation.unapply)("location", "elevation")
  
  implicit def googleApiResultFormat: CodecJson[GoogleApiResult] = casecodec2(GoogleApiResult.apply, GoogleApiResult.unapply)("status", "results")
  
  
  object Main extends App {
  // we need an ActorSystem to host our application in
  implicit val system = ActorSystem("simple-spray-client")
  
  // execution context for futures below
  val log = Logging(system, getClass)
  
  log.info("Requesting the elevation of Mt. Everest from Googles Elevation API...")
  
  val pipeline = sendReceive
  
  val responseFuture= pipeline {
    Get("http://maps.googleapis.com/maps/api/elevation/json?locations=27.988056,86.925278&amp;sensor=false")
  }
  
  responseFuture.onComplete {
    case Success(result) =&gt;
      println(result)
      log.info("The elevation of Mt.Everest is: {} m", result.toString.decodeOption[Elevation].get)
      shutdown()
  
    case Failure(error) =&gt;
      log.error(error, "Couldn't get elevation")
      shutdown()
  }
  def shutdown(): Unit = {
    IO(Http).ask(Http.CloseAll)(1.second).await
    system.shutdown()
  }
   }
  
  }`
  </code></pre>