monix.reactive.internal.builders.ResourceCaseObservable.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
package internal
package builders
import cats.effect.ExitCase
import monix.execution.Callback
import monix.eval.Task
import monix.execution.Ack.{Continue, Stop}
import monix.execution.Cancelable
import monix.execution.cancelables.AssignableCancelable
import monix.reactive.observables.ChainedObservable
import monix.reactive.observers.Subscriber
import scala.util.Success
private[reactive] final class ResourceCaseObservable[A](
acquire: Task[A],
release: (A, ExitCase[Throwable]) => Task[Unit])
extends ChainedObservable[A] {
def unsafeSubscribeFn(conn: AssignableCancelable.Multi, subscriber: Subscriber[A]): Unit = {
implicit val s = subscriber.scheduler
acquire.runAsyncUncancelable(new Callback[Throwable, A] {
def onSuccess(value: A): Unit = {
conn := new StreamOne(value)
.guaranteeCase(e => release(value, e))
.unsafeSubscribeFn(subscriber)
}
def onError(ex: Throwable): Unit =
subscriber.onError(ex)
})
}
private final class StreamOne(value: A) extends Observable[A] {
def unsafeSubscribeFn(out: Subscriber[A]): Cancelable = {
import monix.execution.schedulers.TrampolineExecutionContext.immediate
out.onNext(value) match {
case Continue =>
out.onComplete()
case Stop =>
()
case async =>
async.onComplete {
case Success(Continue) => out.onComplete()
case _ => ()
}(immediate)
}
Cancelable.empty
}
}
}