我正在使用spray-client,希望使用spray-json(与之搭配)从谷歌地图API中获取一个经纬度对象。为此,我需要将整个响应结构设置好:
case class AddrComponent(long_name: String, short_name: String, types: List[String])
case class Location(lat: Double, lng: Double)
case class ViewPort(northeast: Location, southwest: Location)
case class Geometry(location: Location, location_type: String, viewport: ViewPort)
case class EachResult(address_components: List[AddrComponent],
formatted_address: String,
geometry: Geometry,
types: List[String])
case class GoogleApiResult[T](status: String, results: List[T])
object AddressProtocol extends DefaultJsonProtocol {
implicit val addrFormat = jsonFormat3(AddrComponent)
implicit val locFormat = jsonFormat2(Location)
implicit val viewPortFormat = jsonFormat2(ViewPort)
implicit val geomFormat = jsonFormat3(Geometry)
implicit val eachResFormat = jsonFormat4(EachResult)
implicit def GoogleApiFormat[T: JsonFormat] = jsonFormat2(GoogleApiResult.apply[T])
}
import AddressProtocol._
有没有办法从响应的json中只获取Location
并避免所有这些冗长的代码?
spray-client 代码:
implicit val system = ActorSystem("test-system")
import system.dispatcher
private val pipeline = sendReceive ~> unmarshal[GoogleApiResult[EachResult]]
def getPostcode(postcode: String): Point = {
val url = s"http://maps.googleapis.com/maps/api/geocode/json?address=$postcode,+UK&sensor=true"
val future = pipeline(Get(url))
val result = Await.result(future, 10 seconds)
result.results.size match {
case 0 => throw new PostcodeNotFoundException(postcode)
case x if x > 1 => throw new MultipleResultsException(postcode)
case _ => {
val location = result.results(0).geometry.location
new Point(location.lng, location.lat)
}
}
}
或者,我如何在spray-client中使用jackson?