56 lines
1.5 KiB
Scala
56 lines
1.5 KiB
Scala
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/**
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* Copyright (C) 2015 Typesafe <http://typesafe.com/>
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*/
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package docs.stream.cookbook
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import akka.stream.scaladsl.{ Sink, Source }
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import scala.collection.immutable
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import scala.concurrent.{ Await, Future }
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import scala.concurrent.duration._
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class RecipeSeq extends RecipeSpec {
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"Recipe for draining a stream into a strict collection" must {
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"work" in {
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//#draining-to-seq-unsafe
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val result = immutable.Seq[Message]("1", "2", "3")
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val myData = Source(result)
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val unsafe: Future[Seq[Message]] = myData.runWith(Sink.seq) // dangerous!
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//#draining-to-seq-unsafe
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Await.result(unsafe, 3.seconds) should be(result)
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}
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"work together with limit(n)" in {
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//#draining-to-seq-safe
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val result = List("1", "2", "3")
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val myData = Source(result)
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val max = 100
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// OK. Future will fail with a `StreamLimitReachedException`
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// if the number of incoming elements is larger than max
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val safe1: Future[immutable.Seq[Message]] = myData.limit(max).runWith(Sink.seq)
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//#draining-to-seq-safe
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Await.result(safe1, 3.seconds) should be(result)
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}
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"work together with take(n)" in {
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val result = List("1", "2", "3")
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val myData = Source(result)
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val max = 100
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//#draining-to-seq-safe
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// OK. Collect up until max-th elements only, then cancel upstream
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val safe2: Future[immutable.Seq[Message]] = myData.take(max).runWith(Sink.seq)
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//#draining-to-seq-safe
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Await.result(safe2, 3.seconds) should be(result)
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}
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}
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}
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