pekko/akka-stream/src/main/scala/akka/stream/impl/io/OutputStreamSubscriber.scala
Martynas Mickevičius f2553eb3b6 #19446 #18869 Add IOResult
which is used as a materialized value for Sources/Sinks that work with IO.
2016-01-21 18:06:42 +02:00

68 lines
2 KiB
Scala

/**
* Copyright (C) 2015 Typesafe Inc. <http://www.typesafe.com>
*/
package akka.stream.impl.io
import java.io.OutputStream
import akka.Done
import akka.actor.{ Deploy, ActorLogging, Props }
import akka.stream.actor.{ ActorSubscriberMessage, WatermarkRequestStrategy }
import akka.stream.io.IOResult
import akka.util.ByteString
import scala.concurrent.Promise
import scala.util.{ Failure, Success }
/** INTERNAL API */
private[akka] object OutputStreamSubscriber {
def props(os: OutputStream, completionPromise: Promise[IOResult], bufSize: Int) = {
require(bufSize > 0, "buffer size must be > 0")
Props(classOf[OutputStreamSubscriber], os, completionPromise, bufSize).withDeploy(Deploy.local)
}
}
/** INTERNAL API */
private[akka] class OutputStreamSubscriber(os: OutputStream, completionPromise: Promise[IOResult], bufSize: Int)
extends akka.stream.actor.ActorSubscriber
with ActorLogging {
override protected val requestStrategy = WatermarkRequestStrategy(highWatermark = bufSize)
private var bytesWritten: Long = 0
def receive = {
case ActorSubscriberMessage.OnNext(bytes: ByteString)
try {
// blocking write
os.write(bytes.toArray)
bytesWritten += bytes.length
} catch {
case ex: Exception
completionPromise.success(IOResult(bytesWritten, Failure(ex)))
cancel()
}
case ActorSubscriberMessage.OnError(ex)
log.error(ex, "Tearing down OutputStreamSink due to upstream error, wrote bytes: {}", bytesWritten)
completionPromise.success(IOResult(bytesWritten, Failure(ex)))
context.stop(self)
case ActorSubscriberMessage.OnComplete
context.stop(self)
os.flush()
}
override def postStop(): Unit = {
try {
if (os ne null) os.close()
} catch {
case ex: Exception
completionPromise.success(IOResult(bytesWritten, Failure(ex)))
}
completionPromise.trySuccess(IOResult(bytesWritten, Success(Done)))
super.postStop()
}
}