scala - 如何使用 Akka 以一秒的延迟限制 Futures

Question

我有一个 URI 列表，我想在请求之间延迟一秒。我该怎么做？

val uris: List[String] = List()
// How to make these URIs resolve 1 second apart?
val responses: List[Future[Response]] = uris.map(httpRequest(_))

Answer 1

您可以从 URI 列表中创建一个 Akka Streams Source，然后 throttle每个 URI 到 Future[Response] 的转换:

def httpRequest(uri: String): Future[Response] = ???

val uris: List[String] = ???

val responses: Future[Seq[Response]] =
  Source(uris)
    .throttle(1, 1 second)
    .mapAsync(parallelism = 1)(httpRequest)
    .runWith(Sink.seq[Response])