Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance. Project price only 1 $
You can buy this project and download/modify it how often you want.
/*
* Copyright (C) 2016-2020 Lightbend Inc.
*/
package akka.actor
import java.util.Optional
import java.util.concurrent._
import java.util.concurrent.TimeUnit.MILLISECONDS
import java.util.concurrent.atomic.AtomicReference
import java.util.function.Supplier
import scala.annotation.tailrec
import scala.compat.java8.FutureConverters._
import scala.compat.java8.OptionConverters._
import scala.concurrent.{ Await, ExecutionContext, Future, Promise }
import scala.concurrent.duration._
import scala.concurrent.duration.FiniteDuration
import scala.util.Try
import scala.util.control.NonFatal
import com.typesafe.config.Config
import com.typesafe.config.ConfigFactory
import akka.Done
import akka.annotation.InternalApi
import akka.dispatch.ExecutionContexts
import akka.event.Logging
import akka.pattern.after
import akka.util.OptionVal
object CoordinatedShutdown extends ExtensionId[CoordinatedShutdown] with ExtensionIdProvider {
/**
* The first pre-defined phase that applications can add tasks to.
* Note that more phases can be added in the application's
* configuration by overriding this phase with an additional
* depends-on.
*/
val PhaseBeforeServiceUnbind = "before-service-unbind"
/**
* Stop accepting new incoming requests in for example HTTP.
*/
val PhaseServiceUnbind = "service-unbind"
/**
* Wait for requests that are in progress to be completed.
*/
val PhaseServiceRequestsDone = "service-requests-done"
/**
* Final shutdown of service endpoints.
*/
val PhaseServiceStop = "service-stop"
/**
* Phase for custom application tasks that are to be run
* after service shutdown and before cluster shutdown.
*/
val PhaseBeforeClusterShutdown = "before-cluster-shutdown"
/**
* Graceful shutdown of the Cluster Sharding regions.
*/
val PhaseClusterShardingShutdownRegion = "cluster-sharding-shutdown-region"
/**
* Emit the leave command for the node that is shutting down.
*/
val PhaseClusterLeave = "cluster-leave"
/**
* Shutdown cluster singletons
*/
val PhaseClusterExiting = "cluster-exiting"
/**
* Wait until exiting has been completed
*/
val PhaseClusterExitingDone = "cluster-exiting-done"
/**
* Shutdown the cluster extension
*/
val PhaseClusterShutdown = "cluster-shutdown"
/**
* Phase for custom application tasks that are to be run
* after cluster shutdown and before ActorSystem termination.
*/
val PhaseBeforeActorSystemTerminate = "before-actor-system-terminate"
/**
* Last phase. See terminate-actor-system and exit-jvm above.
* Don't add phases that depends on this phase because the
* dispatcher and scheduler of the ActorSystem have been shutdown.
*/
val PhaseActorSystemTerminate = "actor-system-terminate"
/**
* Reason for the shutdown, which can be used by tasks in case they need to do
* different things depending on what caused the shutdown. There are some
* predefined reasons, but external libraries applications may also define
* other reasons.
*/
trait Reason
/**
* Scala API: The reason for the shutdown was unknown. Needed for backwards compatibility.
*/
case object UnknownReason extends Reason
/**
* Java API: The reason for the shutdown was unknown. Needed for backwards compatibility.
*/
def unknownReason: Reason = UnknownReason
/**
* Scala API: The shutdown was initiated by ActorSystem.terminate.
*/
case object ActorSystemTerminateReason extends Reason
/**
* Java API: The shutdown was initiated by ActorSystem.terminate.
*/
def actorSystemTerminateReason: Reason = ActorSystemTerminateReason
/**
* Scala API: The shutdown was initiated by a JVM shutdown hook, e.g. triggered by SIGTERM.
*/
case object JvmExitReason extends Reason
/**
* Java API: The shutdown was initiated by a JVM shutdown hook, e.g. triggered by SIGTERM.
*/
def jvmExitReason: Reason = JvmExitReason
/**
* Scala API: The shutdown was initiated by Cluster downing.
*/
case object ClusterDowningReason extends Reason
/**
* Java API: The shutdown was initiated by Cluster downing.
*/
def clusterDowningReason: Reason = ClusterDowningReason
/**
* Scala API: The shutdown was initiated by a failure to join a seed node.
*/
case object ClusterJoinUnsuccessfulReason extends Reason
/**
* Java API: The shutdown was initiated by a failure to join a seed node.
*/
def clusterJoinUnsuccessfulReason: Reason = ClusterJoinUnsuccessfulReason
/**
* Scala API: The shutdown was initiated by a configuration clash within the existing cluster and the joining node
*/
case object IncompatibleConfigurationDetectedReason extends Reason
/**
* Java API: The shutdown was initiated by a configuration clash within the existing cluster and the joining node
*/
def incompatibleConfigurationDetectedReason: Reason = IncompatibleConfigurationDetectedReason
/**
* Scala API: The shutdown was initiated by Cluster leaving.
*/
case object ClusterLeavingReason extends Reason
/**
* Java API: The shutdown was initiated by Cluster leaving.
*/
def clusterLeavingReason: Reason = ClusterLeavingReason
@volatile private var runningJvmHook = false
override def get(system: ActorSystem): CoordinatedShutdown = super.get(system)
override def get(system: ClassicActorSystemProvider): CoordinatedShutdown = super.get(system)
override def lookup = CoordinatedShutdown
override def createExtension(system: ExtendedActorSystem): CoordinatedShutdown = {
val conf = system.settings.config.getConfig("akka.coordinated-shutdown")
val phases = phasesFromConfig(conf)
val coord = new CoordinatedShutdown(system, phases)
initPhaseActorSystemTerminate(system, conf, coord)
initJvmHook(system, conf, coord)
// Avoid leaking actor system references when system is terminated before JVM is #23384
// Catching RejectedExecutionException in case extension is accessed first time when
// system is already terminated, see #25592. The extension is eagerly loaded when ActorSystem
// is started but it might be a race between (failing?) startup and shutdown.
def cleanupActorSystemJvmHook(): Unit = {
coord.actorSystemJvmHook match {
case OptionVal.Some(cancellable) if !runningJvmHook && !cancellable.isCancelled =>
cancellable.cancel()
coord.actorSystemJvmHook = OptionVal.None
case _ =>
}
}
try system.registerOnTermination(cleanupActorSystemJvmHook())
catch {
case _: RejectedExecutionException => cleanupActorSystemJvmHook()
}
coord
}
// locate reason-specific overrides and merge with defaults.
@InternalApi private[akka] def confWithOverrides(conf: Config, reason: Option[Reason]): Config = {
reason
.flatMap { r =>
val basePath = s"""reason-overrides."${r.getClass.getName}""""
if (conf.hasPath(basePath)) Some(conf.getConfig(basePath).withFallback(conf)) else None
}
.getOrElse(conf)
}
private def initPhaseActorSystemTerminate(
system: ExtendedActorSystem,
conf: Config,
coord: CoordinatedShutdown): Unit = {
coord.addTask(PhaseActorSystemTerminate, "terminate-system") { () =>
val confForReason = confWithOverrides(conf, coord.shutdownReason())
val terminateActorSystem = confForReason.getBoolean("terminate-actor-system")
val exitJvm = confForReason.getBoolean("exit-jvm")
val exitCode = confForReason.getInt("exit-code")
if (exitJvm && terminateActorSystem) {
// In case ActorSystem shutdown takes longer than the phase timeout,
// exit the JVM forcefully anyway.
// We must spawn a separate thread to not block current thread,
// since that would have blocked the shutdown of the ActorSystem.
val timeout = coord.timeout(PhaseActorSystemTerminate)
val t = new Thread {
override def run(): Unit = {
if (Try(Await.ready(system.whenTerminated, timeout)).isFailure && !runningJvmHook)
System.exit(exitCode)
}
}
t.setName("CoordinatedShutdown-exit")
t.start()
}
if (terminateActorSystem) {
system.finalTerminate()
system.whenTerminated.map { _ =>
if (exitJvm && !runningJvmHook) System.exit(exitCode)
Done
}(ExecutionContexts.parasitic)
} else if (exitJvm) {
System.exit(exitCode)
Future.successful(Done)
} else
Future.successful(Done)
}
}
private def initJvmHook(system: ActorSystem, conf: Config, coord: CoordinatedShutdown): Unit = {
val runByJvmShutdownHook = system.settings.JvmShutdownHooks && conf.getBoolean("run-by-jvm-shutdown-hook")
if (runByJvmShutdownHook) {
coord.actorSystemJvmHook = OptionVal.Some(coord.addCancellableJvmShutdownHook {
runningJvmHook = true // avoid System.exit from PhaseActorSystemTerminate task
if (!system.whenTerminated.isCompleted) {
coord.log.debug("Starting coordinated shutdown from JVM shutdown hook")
try {
// totalTimeout will be 0 when no tasks registered, so at least 3.seconds
val totalTimeout = coord.totalTimeout().max(3.seconds)
Await.ready(coord.run(JvmExitReason), totalTimeout)
} catch {
case NonFatal(e) =>
coord.log.warning("CoordinatedShutdown from JVM shutdown failed: {}", e.getMessage)
}
}
})
}
}
/**
* INTERNAL API
*/
private[akka] final case class Phase(
dependsOn: Set[String],
timeout: FiniteDuration,
recover: Boolean,
enabled: Boolean)
/**
* INTERNAL API
*/
private[akka] def phasesFromConfig(conf: Config): Map[String, Phase] = {
import akka.util.ccompat.JavaConverters._
val defaultPhaseTimeout = conf.getString("default-phase-timeout")
val phasesConf = conf.getConfig("phases")
val defaultPhaseConfig = ConfigFactory.parseString(s"""
timeout = $defaultPhaseTimeout
recover = true
enabled = true
depends-on = []
""")
phasesConf.root.unwrapped.asScala.toMap.map {
case (k, _: java.util.Map[_, _]) =>
val c = phasesConf.getConfig(k).withFallback(defaultPhaseConfig)
val dependsOn = c.getStringList("depends-on").asScala.toSet
val timeout = c.getDuration("timeout", MILLISECONDS).millis
val recover = c.getBoolean("recover")
val enabled = c.getBoolean("enabled")
k -> Phase(dependsOn, timeout, recover, enabled)
case (k, v) =>
throw new IllegalArgumentException(s"Expected object value for [$k], got [$v]")
}
}
/**
* INTERNAL API: https://en.wikipedia.org/wiki/Topological_sorting
*/
private[akka] def topologicalSort(phases: Map[String, Phase]): List[String] = {
var result = List.empty[String]
var unmarked = phases.keySet ++ phases.values.flatMap(_.dependsOn) // in case phase is not defined as key
var tempMark = Set.empty[String] // for detecting cycles
while (unmarked.nonEmpty) {
depthFirstSearch(unmarked.head)
}
def depthFirstSearch(u: String): Unit = {
if (tempMark(u))
throw new IllegalArgumentException(
"Cycle detected in graph of phases. It must be a DAG. " +
s"phase [$u] depends transitively on itself. All dependencies: $phases")
if (unmarked(u)) {
tempMark += u
phases.get(u) match {
case Some(p) => p.dependsOn.foreach(depthFirstSearch)
case None =>
}
unmarked -= u // permanent mark
tempMark -= u
result = u :: result
}
}
result.reverse
}
}
final class CoordinatedShutdown private[akka] (
system: ExtendedActorSystem,
phases: Map[String, CoordinatedShutdown.Phase])
extends Extension {
import CoordinatedShutdown.{ Reason, UnknownReason }
/** INTERNAL API */
private[akka] val log = Logging(system, getClass)
private val knownPhases = phases.keySet ++ phases.values.flatMap(_.dependsOn)
/** INTERNAL API */
private[akka] val orderedPhases = CoordinatedShutdown.topologicalSort(phases)
private trait PhaseDefinition {
def size: Int
def run(recoverEnabled: Boolean)(implicit ec: ExecutionContext): Future[Done]
}
private object tasks {
private val registeredPhases = new ConcurrentHashMap[String, StrictPhaseDefinition]()
private trait TaskDefinition extends Cancellable {
private[tasks] def run(recoverEnabled: Boolean)(implicit ec: ExecutionContext): Future[Done]
}
private object TaskDefinition {
def apply(phaseName: String, task: () => Future[Done], name: String): TaskDefinition = new TaskDefinition {
// This is a vanilla class instead of a case class to avoid default implementations of .hashCode() and .equals
// Different code paths could register the same task under the same name multiple times; in this case we want to
// run that task as many times as it was registered (minus the number of times those were cancelled), so they must
// be distinct in a Set[TaskDefinition].
private sealed trait TaskState
private case object Pending extends TaskState
private case object Cancelled extends TaskState
private case class Running(job: Promise[Done]) extends TaskState
private val taskState = new AtomicReference[TaskState](Pending)
@tailrec
override private[tasks] def run(recoverEnabled: Boolean)(implicit ec: ExecutionContext): Future[Done] = {
val job = Promise[Done]()
val nextTaskState = taskState.updateAndGet {
case Pending => Running(job)
case Cancelled => Cancelled
case Running(otherJob) => Running(otherJob)
}
nextTaskState match {
case Running(runningJob) if runningJob == job =>
// only start the job if atomic update succeeds and we were the winner of any race
if (log.isDebugEnabled) {
log.debug("Performing task [{}] in CoordinatedShutdown phase [{}]", name, phaseName)
}
job.completeWith(try {
task.apply().recover {
case NonFatal(exc) if recoverEnabled =>
log.warning("Task [{}] failed in phase [{}]: {}", name, phaseName, exc.getMessage)
Done
}
} catch { // in case task.apply() throws
case NonFatal(exc) if recoverEnabled =>
log.warning(
"Task [{}] in phase [{}] threw an exception before its future could be constructed: {}",
name,
phaseName,
exc.getMessage)
Future.successful(Done)
case NonFatal(exc) =>
Future.failed(exc)
})
job.future
case Running(otherJob) =>
log.warning("Task [{}] in phase [{}] was invoked multiple times and deduplicated.", name, phaseName)
otherJob.future
case Cancelled =>
Future.successful(Done)
case Pending =>
log.error("Atomic update produced an impossible value; this should never happen!")
run(recoverEnabled)
}
}
override def cancel(): Boolean = {
val nextTaskState = taskState.updateAndGet {
case Pending => Cancelled
case other => other
}
nextTaskState match {
case Cancelled =>
registeredPhases
.merge(phaseName, StrictPhaseDefinition.empty, (previous, incoming) => previous.merge(incoming))
if (log.isDebugEnabled) {
log.debug("Successfully cancelled CoordinatedShutdown task [{}] from phase [{}].", name, phaseName)
}
true
case _ =>
false
}
}
// must be side-effect free
override def isCancelled: Boolean = {
taskState.get() == Cancelled
}
}
}
private case class StrictPhaseDefinition(tasks: Set[TaskDefinition]) extends PhaseDefinition {
// This is a case class so that the update methods on ConcurrentHashMap can correctly deal with equality
override val size: Int = tasks.size
override def run(recoverEnabled: Boolean)(implicit ec: ExecutionContext): Future[Done] = {
Future.sequence(tasks.map(_.run(recoverEnabled))).map(_ => Done)(ExecutionContexts.parasitic)
}
// This method may be run multiple times during the compare-and-set loop of ConcurrentHashMap, so it must be side-effect-free
def merge(other: StrictPhaseDefinition): StrictPhaseDefinition = {
val nextTasks = (tasks ++ other.tasks).filterNot(_.isCancelled)
copy(tasks = nextTasks)
}
}
private object StrictPhaseDefinition {
def single(taskDefinition: TaskDefinition): StrictPhaseDefinition = {
StrictPhaseDefinition(Set(taskDefinition))
}
val empty: StrictPhaseDefinition = StrictPhaseDefinition(Set.empty)
}
def get(phaseName: String): Option[PhaseDefinition] = Option(registeredPhases.get(phaseName))
def totalDuration(): FiniteDuration = {
import akka.util.ccompat.JavaConverters._
registeredPhases.keySet.asScala.foldLeft(Duration.Zero) {
case (acc, phase) =>
acc + timeout(phase)
}
}
def register(phaseName: String, task: () => Future[Done], name: String): Cancellable = {
val cancellable: TaskDefinition = TaskDefinition(phaseName, task, name)
registeredPhases.merge(
phaseName,
StrictPhaseDefinition.single(cancellable),
(previous, incoming) => previous.merge(incoming))
cancellable
}
}
private val runStarted = new AtomicReference[Option[Reason]](None)
private val runPromise = Promise[Done]()
private val _jvmHooksLatch = new AtomicReference[CountDownLatch](new CountDownLatch(0))
@volatile private var actorSystemJvmHook: OptionVal[Cancellable] = OptionVal.None
/**
* INTERNAL API
*/
private[akka] lazy val terminationWatcher =
system.systemActorOf(CoordinatedShutdownTerminationWatcher.props, "coordinatedShutdownTerminationWatcher")
/**
* INTERNAL API
*/
private[akka] def jvmHooksLatch: CountDownLatch = _jvmHooksLatch.get
/**
* Scala API: Add a task to a phase, returning an object which will cancel it
* on demand and remove it from the task pool (so long as the same task has not
* been added elsewhere). Tasks in a phase are run concurrently, with no ordering
* assumed.
*
* Adding a task to a phase does not remove any other tasks from the phase.
*
* If the same task is added multiple times, each addition will be run unless cancelled.
*
* Tasks should typically be registered as early as possible -- once coordinated
* shutdown begins, tasks may be added without ever being run. A task may add tasks
* to a later stage with confidence that they will be run.
*/
def addCancellableTask(phase: String, taskName: String)(task: () => Future[Done]): Cancellable = {
require(
knownPhases(phase),
s"Unknown phase [$phase], known phases [$knownPhases]. All phases (along with their optional dependencies) must be defined in configuration")
require(
taskName.nonEmpty,
"Set a task name when adding tasks to the Coordinated Shutdown. " +
"Try to use unique, self-explanatory names.")
tasks.register(phase, task, taskName)
}
/**
* Java API: Add a task to a phase, returning an object which will cancel it
* on demand and remove it from the task pool (so long as the same task has not
* been added elsewhere). Tasks in a phase are run concurrently, with no ordering
* assumed.
*
* Adding a task to a phase does not remove any other tasks from the phase.
*
* If the same task is added multiple times, each addition will be run unless cancelled.
*
* Tasks should typically be registered as early as possible -- once coordinated
* shutdown begins, tasks may be added without ever being run. A task may add tasks
* to a later stage with confidence that they will be run.
*/
def addCancellableTask(phase: String, taskName: String, task: Supplier[CompletionStage[Done]]): Cancellable = {
addCancellableTask(phase, taskName)(() => task.get().toScala)
}
/**
* Scala API: Add a task to a phase. It doesn't remove previously added tasks.
* Tasks added to the same phase are executed in parallel without any
* ordering assumptions. Next phase will not start until all tasks of
* previous phase have been completed.
*
* Tasks should typically be registered as early as possible after system
* startup. When running the coordinated shutdown tasks that have been registered
* will be performed but tasks that are added too late will not be run.
* It is possible to add a task to a later phase by a task in an earlier phase
* and it will be performed.
*/
def addTask(phase: String, taskName: String)(task: () => Future[Done]): Unit = {
require(
knownPhases(phase),
s"Unknown phase [$phase], known phases [$knownPhases]. " +
"All phases (along with their optional dependencies) must be defined in configuration")
require(
taskName.nonEmpty,
"Set a task name when adding tasks to the Coordinated Shutdown. " +
"Try to use unique, self-explanatory names.")
tasks.register(phase, task, taskName)
}
/**
* Java API: Add a task to a phase. It doesn't remove previously added tasks.
* Tasks added to the same phase are executed in parallel without any
* ordering assumptions. Next phase will not start until all tasks of
* previous phase have been completed.
*
* Tasks should typically be registered as early as possible after system
* startup. When running the coordinated shutdown tasks that have been registered
* will be performed but tasks that are added too late will not be run.
* It is possible to add a task to a later phase by a task in an earlier phase
* and it will be performed.
*/
def addTask(phase: String, taskName: String, task: Supplier[CompletionStage[Done]]): Unit =
addTask(phase, taskName)(() => task.get().toScala)
/**
* Scala API: Add an actor termination task to a phase. It doesn't remove
* previously added tasks. Tasks added to the same phase are executed in
* parallel without any ordering assumptions. Next phase will not start until
* all tasks of previous phase have been completed.
*
* When executed, this task will first send the given stop message, if defined,
* to the actor, then it will watch the actor, and complete when the actor
* terminates.
*
* Tasks should typically be registered as early as possible after system
* startup. When running the coordinated shutdown tasks that have been registered
* will be performed but tasks that are added too late will not be run.
* It is possible to add a task to a later phase by a task in an earlier phase
* and it will be performed.
*/
def addActorTerminationTask(phase: String, taskName: String, actor: ActorRef, stopMsg: Option[Any]): Unit =
addTask(phase, taskName) { () =>
stopMsg.foreach(msg => actor ! msg)
// addTask will verify that phases(phase) exists, so this should be safe
val deadline = phases(phase).timeout.fromNow
// Note: we cannot use ask because we cannot spawn actors during shutdown
val completionPromise = Promise[Done]()
terminationWatcher ! CoordinatedShutdownTerminationWatcher.Watch(actor, deadline, completionPromise)
completionPromise.future
}
/**
* Java API: Add an actor termination task to a phase. It doesn't remove
* previously added tasks. Tasks added to the same phase are executed in
* parallel without any ordering assumptions. Next phase will not start until
* all tasks of previous phase have been completed.
*
* When executed, this task will first send the given stop message, if defined,
* to the actor, then it will watch the actor, and complete when the actor
* terminates.
*
* Tasks should typically be registered as early as possible after system
* startup. When running the coordinated shutdown tasks that have been registered
* will be performed but tasks that are added too late will not be run.
* It is possible to add a task to a later phase by a task in an earlier phase
* and it will be performed.
*/
def addActorTerminationTask(phase: String, taskName: String, actor: ActorRef, stopMsg: Optional[Any]): Unit =
addActorTerminationTask(phase, taskName, actor, stopMsg.asScala)
/**
* The `Reason` for the shutdown as passed to the `run` method. `None` if the shutdown
* has not been started.
*/
def shutdownReason(): Option[Reason] = runStarted.get()
/**
* The `Reason` for the shutdown as passed to the `run` method. `Optional.empty` if the shutdown
* has not been started.
*/
def getShutdownReason(): Optional[Reason] = shutdownReason().asJava
/**
* Scala API: Run tasks of all phases. The returned
* `Future` is completed when all tasks have been completed,
* or there is a failure when recovery is disabled.
*
* It's safe to call this method multiple times. It will only run the shutdown sequence once.
*/
def run(reason: Reason): Future[Done] = run(reason, None)
@deprecated("Use the method with `reason` parameter instead", since = "2.5.8")
def run(): Future[Done] = run(UnknownReason)
/**
* Java API: Run tasks of all phases. The returned
* `CompletionStage` is completed when all tasks have been completed,
* or there is a failure when recovery is disabled.
*
* It's safe to call this method multiple times. It will only run the shutdown sequence once.
*/
def runAll(reason: Reason): CompletionStage[Done] = run(reason).toJava
@deprecated("Use the method with `reason` parameter instead", since = "2.5.8")
def runAll(): CompletionStage[Done] = runAll(UnknownReason)
/**
* Scala API: Run tasks of all phases including and after the given phase.
* The returned `Future` is completed when all such tasks have been completed,
* or there is a failure when recovery is disabled.
*
* It's safe to call this method multiple times. It will only run shutdown sequence once.
*/
def run(reason: Reason, fromPhase: Option[String]): Future[Done] = {
if (runStarted.compareAndSet(None, Some(reason))) {
implicit val ec: ExecutionContext = system.dispatchers.internalDispatcher
val debugEnabled = log.isDebugEnabled
log.debug("Running CoordinatedShutdown with reason [{}]", reason)
def loop(remainingPhases: List[String]): Future[Done] = {
remainingPhases match {
case Nil => Future.successful(Done)
case phaseName :: remaining if !phases(phaseName).enabled =>
tasks.get(phaseName).foreach { phaseDef =>
log.info(s"Phase [{}] disabled through configuration, skipping [{}] tasks.", phaseName, phaseDef.size)
}
loop(remaining)
case phaseName :: remaining =>
val phaseResult = tasks.get(phaseName) match {
case None =>
if (debugEnabled) log.debug("Performing phase [{}] with [0] tasks", phaseName)
Future.successful(Done)
case Some(phaseDef) =>
if (debugEnabled) {
log.debug("Performing phase [{}] with [{}] tasks.", phaseName, phaseDef.size)
}
val recoverEnabled = phases(phaseName).recover
val result = phaseDef.run(recoverEnabled)
val timeout = phases(phaseName).timeout
val deadline = Deadline.now + timeout
val timeoutFut = try {
after(timeout, system.scheduler) {
if (phaseName == CoordinatedShutdown.PhaseActorSystemTerminate && deadline.hasTimeLeft()) {
// too early, i.e. triggered by system termination
result
} else if (result.isCompleted)
Future.successful(Done)
else if (recoverEnabled) {
log.warning("Coordinated shutdown phase [{}] timed out after {}", phaseName, timeout)
Future.successful(Done)
} else
Future.failed(
new TimeoutException(s"Coordinated shutdown phase [$phaseName] timed out after $timeout"))
}
} catch {
case _: IllegalStateException =>
// The call to `after` threw IllegalStateException, triggered by system termination
result
}
Future.firstCompletedOf(List(result, timeoutFut))
}
if (remaining.isEmpty)
phaseResult // avoid flatMap when system terminated in last phase
else
phaseResult.flatMap(_ => loop(remaining))
}
}
val remainingPhases = fromPhase match {
case None => orderedPhases // all
case Some(p) => orderedPhases.dropWhile(_ != p)
}
val done = loop(remainingPhases)
runPromise.completeWith(done)
}
runPromise.future
}
@deprecated("Use the method with `reason` parameter instead", since = "2.5.8")
def run(fromPhase: Option[String]): Future[Done] =
run(UnknownReason, fromPhase)
/**
* Java API: Run tasks of all phases including and after the given phase.
* The returned `CompletionStage` is completed when all such tasks have been completed,
* or there is a failure when recovery is disabled.
*
* It's safe to call this method multiple times. It will only run the shutdown sequence once.
*/
def run(reason: Reason, fromPhase: Optional[String]): CompletionStage[Done] =
run(reason, fromPhase.asScala).toJava
@deprecated("Use the method with `reason` parameter instead", since = "2.5.8")
def run(fromPhase: Optional[String]): CompletionStage[Done] =
run(UnknownReason, fromPhase)
/**
* The configured timeout for a given `phase`.
* For example useful as timeout when actor `ask` requests
* is used as a task.
*/
def timeout(phase: String): FiniteDuration =
phases.get(phase) match {
case Some(p) => p.timeout
case None =>
throw new IllegalArgumentException(s"Unknown phase [$phase]. All phases must be defined in configuration")
}
/**
* Sum of timeouts of all phases that have some task.
*/
def totalTimeout(): FiniteDuration = {
tasks.totalDuration()
}
/**
* Scala API: Add a JVM shutdown hook that will be run when the JVM process
* begins its shutdown sequence. Added hooks may run in any order
* concurrently, but they are running before Akka internal shutdown
* hooks, e.g. those shutting down Artery.
*/
def addJvmShutdownHook[T](hook: => T): Unit = addCancellableJvmShutdownHook(hook)
/**
* Scala API: Add a JVM shutdown hook that will be run when the JVM process
* begins its shutdown sequence. Added hooks may run in any order
* concurrently, but they are running before Akka internal shutdown
* hooks, e.g. those shutting down Artery.
*
* The returned ``Cancellable`` makes it possible to de-register the hook. For example
* on actor system shutdown to avoid leaking references to the actor system in tests.
*
* For shutdown hooks that does not have any requirements on running before the Akka
* shutdown hooks the standard library JVM shutdown hooks APIs are better suited.
*/
@tailrec def addCancellableJvmShutdownHook[T](hook: => T): Cancellable = {
if (runStarted.get.isEmpty) {
val currentLatch = _jvmHooksLatch.get
val newLatch = new CountDownLatch(currentLatch.getCount.toInt + 1)
if (_jvmHooksLatch.compareAndSet(currentLatch, newLatch)) {
val thread = new Thread {
override def run(): Unit = {
try hook
finally _jvmHooksLatch.get.countDown()
}
}
thread.setName(s"${system.name}-shutdown-hook-${newLatch.getCount}")
try {
Runtime.getRuntime.addShutdownHook(thread)
new Cancellable {
@volatile var cancelled = false
def cancel(): Boolean = {
try {
if (Runtime.getRuntime.removeShutdownHook(thread)) {
cancelled = true
_jvmHooksLatch.get.countDown()
true
} else {
false
}
} catch {
case _: IllegalStateException =>
// shutdown already in progress
false
}
}
def isCancelled: Boolean = cancelled
}
} catch {
case e: IllegalStateException =>
// Shutdown in progress, if CoordinatedShutdown is created via a JVM shutdown hook (Artery)
log.warning("Could not addJvmShutdownHook, due to: {}", e.getMessage)
_jvmHooksLatch.get.countDown()
Cancellable.alreadyCancelled
}
} else
addCancellableJvmShutdownHook(hook) // lost CAS, retry
} else {
Cancellable.alreadyCancelled
}
}
/**
* Java API: Add a JVM shutdown hook that will be run when the JVM process
* begins its shutdown sequence. Added hooks may run in any order
* concurrently, but they are running before Akka internal shutdown
* hooks, e.g. those shutting down Artery.
*/
def addJvmShutdownHook(hook: Runnable): Unit =
addJvmShutdownHook(hook.run())
/**
* Java API: Add a JVM shutdown hook that will be run when the JVM process
* begins its shutdown sequence. Added hooks may run in an order
* concurrently, but they are running before Akka internal shutdown
* hooks, e.g. those shutting down Artery.
*
* The returned ``Cancellable`` makes it possible to de-register the hook. For example
* on actor system shutdown to avoid leaking references to the actor system in tests.
*
* For shutdown hooks that does not have any requirements on running before the Akka
* shutdown hooks the standard library JVM shutdown hooks APIs are better suited.
*/
def addCancellableJvmShutdownHook(hook: Runnable): Cancellable =
addCancellableJvmShutdownHook(hook.run())
}
/** INTERNAL API */
@InternalApi
private[akka] object CoordinatedShutdownTerminationWatcher {
final case class Watch(actor: ActorRef, deadline: Deadline, completionPromise: Promise[Done])
private final case class WatchedTimedOut(actor: ActorRef, completionPromise: Promise[Done], timeout: FiniteDuration)
def props: Props = Props(new CoordinatedShutdownTerminationWatcher)
}
/** INTERNAL API */
@InternalApi
private[akka] class CoordinatedShutdownTerminationWatcher extends Actor with Timers {
private var waitingForActor: Map[ActorRef, Set[Promise[Done]]] = Map.empty
private var alreadySeenTerminated = Set.empty[ActorRef]
import CoordinatedShutdownTerminationWatcher._
override def receive: Receive = {
case Watch(actor, deadline, completionPromise) =>
if (alreadySeenTerminated(actor)) completionPromise.trySuccess(Done)
else {
val newWaiting =
waitingForActor.get(actor) match {
case Some(alreadyWaiting) =>
alreadyWaiting + completionPromise
case None =>
context.watch(actor)
Set(completionPromise)
}
waitingForActor = waitingForActor.updated(actor, newWaiting)
timers.startSingleTimer(
completionPromise,
WatchedTimedOut(actor, completionPromise, deadline.time),
deadline.timeLeft)
}
case Terminated(actor) =>
for {
waitingPromises <- waitingForActor.get(actor)
waitingPromise <- waitingPromises
} {
if (waitingPromise.trySuccess(Done)) {
timers.cancel(waitingPromise)
}
}
waitingForActor = waitingForActor - actor
alreadySeenTerminated += actor
case WatchedTimedOut(actor, completionPromise, timeout) =>
if (!completionPromise.isCompleted)
completionPromise.tryFailure(
new TimeoutException(s"Actor [$actor] termination timed out after [$timeout] during coordinated shutdown"))
}
}