Change value inside Future(success(Some(List(BN))) - scala

Question

I have a class as
case class BN[A] (val BNId: Long, score: Double, child: A)
and a database as BnDAO
class BnDAO(...) {
def readAsync(info : scala.Long)(implicit ec : scala.concurrent.ExecutionContext) : scala.concurrent.Future[scala.Option[scala.List[BN]]] = { /* compiled code */ }
}
During my function of calling BnDAO to retrieve BN for set of ids, I want to change the result BN's score according to a Map[InfoId: Long, score: Double]
Here is my current code
val infoIds = scoreMap.keys.toSet
val futureBN = infoIds.map {
id =>
val curBN = interestsDAO.readAsync(id)
//curBN is now "Future(Success(Some(List(BN))))"
val curScore = scoreMap.get(id)
//how to change curBN's score with curSocre?
}
Thank you!!
//Thank you for Allen's answer. Based on his answer. Is it possible to create a Set of Future[Option[List[BN]]] and a Map of Long to List[Long] (infoId -> List[BNId]) within one traverse.

Answer 1

I was not sure what you meant, so I created two answers. Pick the one that you want.
import scala.concurrent.duration._
val ids = scoreMap.keys.toVector
val futureBN = ids.map { id =>
val curBNFut = interestsDAO.readAsync(id)
val v = curBNFut.map(opt => opt.map(l =>
id -> l.map(e =>
scoreMap.get(e.id).map(escore => e.copy(score = escore)).getOrElse(e)
)
)
}
val mapResultFut = Future.sequence(futureBN).map(m =>
m.flatMap(identity).toMap
)
val mapResult = Await.result(mapResultFut, 5.seconds)
val setFut = futureBN.map(fut => fut.map{opt => opt.map{case (id, l) => l }}).toSet
or
import scala.concurrent.duration._
val ids = scoreMap.keys.toVector
val futureBN = ids.map { id =>
val curBNFut = interestsDAO.readAsync(id)
val v = curBNFut.map(opt => opt.map(l =>
id -> l.map(e =>
scoreMap.get(id).map(escore => e.copy(score = escore)).getOrElse(e)
)
)
}
val mapResultFut = Future.sequence(futureBN).map(m =>
m.flatMap(identity).toMap
)
val mapResult = Await.result(mapResultFut, 5.seconds)
val setFut = futureBN.map(fut => fut.map{opt => opt.map{case (id, l) => l }}).toSet
The difference is in the input to scoreMap.get
I am not sure which one you want.
Post a comment if there is anything wrong. Make sure to test my answer, so that it is what you want.