monix.reactive.internal.operators.OnCancelTriggerErrorObservable.scala Maven / Gradle / Ivy
/*
* Copyright (c) 2014-2020 by The Monix Project Developers.
* See the project homepage at: https://monix.io
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package monix.reactive.internal.operators
import monix.execution.Ack.{Continue, Stop}
import monix.execution.{Ack, Cancelable}
import monix.reactive.Observable
import monix.reactive.observers.Subscriber
import scala.concurrent.Future
import scala.concurrent.CancellationException
private[reactive] final class OnCancelTriggerErrorObservable[A](source: Observable[A]) extends Observable[A] {
def unsafeSubscribeFn(downstream: Subscriber[A]): Cancelable = {
val out: Subscriber[A] = new Subscriber[A] { self =>
implicit val scheduler = downstream.scheduler
private[this] var isDone = false
def onNext(elem: A): Future[Ack] =
self.synchronized {
if (isDone) Stop
else
stopStreamOnCancel(downstream.onNext(elem))
}
def onError(ex: Throwable): Unit =
self.synchronized {
if (!isDone) {
isDone = true
downstream.onError(ex)
}
}
def onComplete(): Unit =
self.synchronized {
if (!isDone) {
isDone = true
downstream.onComplete()
}
}
private def stopStreamOnCancel(ack: Future[Ack]): Future[Ack] = {
if (ack eq Continue)
Continue
else if (ack eq Stop) {
isDone = true
Stop
} else if (ack.isCompleted) {
val sync = ack.value.get
if (sync.isSuccess) stopStreamOnCancel(sync.get)
else {
isDone = true
scheduler.reportFailure(sync.failed.get)
Stop
}
} else {
ack.onComplete(result => self.synchronized(stopStreamOnCancel(ack)))
ack
}
}
}
val subscription = source.unsafeSubscribeFn(out)
Cancelable(() => {
try out.onError(new CancellationException("Connection was cancelled"))
finally subscription.cancel()
})
}
}