Akka-Http WebSocket: Akka stream use WebSocket as a sink

1
votes

Using Akka-Http and Akka-Streams version 2.4 how can I construct a stream so that it has a sink that is a websocket.

For example I would like to have a source that generates random numbers, these numbers get filtered, lets say keep even numbers, then flow to a WebSocket as a sink.

Thanks

1
scalawebsocketakkaakka-streamakka-http

1 Answers

3
votes

This code put into a akka http route will output a continuous stream of random numbers without overwhelming the websocket

path("randomNums") {
  val src =
    Source.fromIterator(() => Iterator.continually(ThreadLocalRandom.current.nextInt()))
          .filter(i => i > 0 && i % 2 == 0).map(i => TextMessage(i.toString))

    extractUpgradeToWebsocket { upgrade =>
      complete(upgrade.handleMessagesWithSinkSource(Sink.ignore, src))
    }
}