1500d1f36d
A SubFlow (or SubSource) is not a Graph, it is an unfinished builder that accepts transformations. This allows us to capture the substreams’ transformations before materializing the flow, which will be very helpful in fully fusing all operators. Another change is that groupBy now requires a maxSubstreams parameter in order to bound its resource usage. In exchange the matching merge can be unbounded. This trades silent deadlock for explicit stream failure. This commit also changes all uses of Predef.identity to use `conforms` and removes the HTTP impl.util.identityFunc.
37 lines
1.3 KiB
Scala
37 lines
1.3 KiB
Scala
/**
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* Copyright (C) 2015 Typesafe Inc. <http://www.typesafe.com>
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*/
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package akka.stream.impl
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import akka.stream._
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import akka.stream.scaladsl._
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import language.higherKinds
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object SubFlowImpl {
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trait MergeBack[In, F[+_]] {
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def apply[T](f: Flow[In, T, Unit], breadth: Int): F[T]
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}
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}
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class SubFlowImpl[In, Out, Mat, F[+_], C](val subFlow: Flow[In, Out, Unit],
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mergeBackFunction: SubFlowImpl.MergeBack[In, F],
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finishFunction: Sink[In, Unit] ⇒ C)
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extends SubFlow[Out, Mat, F, C] {
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override def deprecatedAndThen[U](op: Stages.StageModule): SubFlow[U, Mat, F, C] =
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new SubFlowImpl[In, U, Mat, F, C](subFlow.deprecatedAndThen(op), mergeBackFunction, finishFunction)
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override def via[T, Mat2](flow: Graph[FlowShape[Out, T], Mat2]): Repr[T] =
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new SubFlowImpl[In, T, Mat, F, C](subFlow.via(flow), mergeBackFunction, finishFunction)
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override def withAttributes(attr: Attributes): SubFlow[Out, Mat, F, C] =
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new SubFlowImpl[In, Out, Mat, F, C](subFlow.withAttributes(attr), mergeBackFunction, finishFunction)
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override def mergeSubstreams: F[Out] = mergeBackFunction(subFlow, Int.MaxValue)
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override def concatSubstreams: F[Out] = mergeBackFunction(subFlow, 1)
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def to[M](sink: Graph[SinkShape[Out], M]): C = finishFunction(subFlow.to(sink))
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}
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