akka.routing.ScatterGatherFirstCompleted.scala Maven / Gradle / Ivy
/*
* Copyright (C) 2009-2019 Lightbend Inc.
*/
package akka.routing
import scala.collection.immutable
import akka.dispatch.Dispatchers
import com.typesafe.config.Config
import akka.actor.SupervisorStrategy
import akka.japi.Util.immutableSeq
import akka.actor.ActorRef
import scala.concurrent.Promise
import akka.pattern.ask
import akka.pattern.pipe
import akka.dispatch.ExecutionContexts
import scala.concurrent.duration.FiniteDuration
import akka.util.Timeout
import akka.util.Helpers.ConfigOps
import akka.util.JavaDurationConverters._
import akka.actor.ActorSystem
import scala.concurrent.Future
import java.util.concurrent.TimeoutException
/**
* Broadcasts the message to all routees, and replies with the first response.
*
* @param within expecting at least one reply within this duration, otherwise
* it will reply with [[akka.pattern.AskTimeoutException]] in a [[akka.actor.Status.Failure]]
*/
@SerialVersionUID(1L)
final case class ScatterGatherFirstCompletedRoutingLogic(within: FiniteDuration) extends RoutingLogic {
override def select(message: Any, routees: immutable.IndexedSeq[Routee]): Routee =
ScatterGatherFirstCompletedRoutees(routees, within)
}
/**
* INTERNAL API
*/
@SerialVersionUID(1L)
private[akka] final case class ScatterGatherFirstCompletedRoutees(
routees: immutable.IndexedSeq[Routee],
within: FiniteDuration)
extends Routee {
override def send(message: Any, sender: ActorRef): Unit =
if (routees.isEmpty) {
implicit val ec = ExecutionContexts.sameThreadExecutionContext
val reply = Future.failed(new TimeoutException("Timeout due to no routees"))
reply.pipeTo(sender)
} else {
implicit val ec = ExecutionContexts.sameThreadExecutionContext
implicit val timeout = Timeout(within)
val promise = Promise[Any]()
routees.foreach {
case ActorRefRoutee(ref) =>
promise.completeWith(ref.ask(message))
case ActorSelectionRoutee(sel) =>
promise.completeWith(sel.ask(message))
case _ =>
}
promise.future.pipeTo(sender)
}
}
/**
* A router pool that broadcasts the message to all routees, and replies with the first response.
*
* The configuration parameter trumps the constructor arguments. This means that
* if you provide `nrOfInstances` during instantiation they will be ignored if
* the router is defined in the configuration file for the actor being used.
*
* Supervision Setup
*
* Any routees that are created by a router will be created as the router's children.
* The router is therefore also the children's supervisor.
*
* The supervision strategy of the router actor can be configured with
* [[#withSupervisorStrategy]]. If no strategy is provided, routers default to
* a strategy of “always escalate”. This means that errors are passed up to the
* router's supervisor for handling.
*
* The router's supervisor will treat the error as an error with the router itself.
* Therefore a directive to stop or restart will cause the router itself to stop or
* restart. The router, in turn, will cause its children to stop and restart.
*
* @param nrOfInstances initial number of routees in the pool
*
* @param resizer optional resizer that dynamically adjust the pool size
*
* @param within expecting at least one reply within this duration, otherwise
* it will reply with [[akka.pattern.AskTimeoutException]] in a [[akka.actor.Status.Failure]]
*
* @param supervisorStrategy strategy for supervising the routees, see 'Supervision Setup'
*
* @param routerDispatcher dispatcher to use for the router head actor, which handles
* supervision, death watch and router management messages
*/
@SerialVersionUID(1L)
final case class ScatterGatherFirstCompletedPool(
nrOfInstances: Int,
override val resizer: Option[Resizer] = None,
within: FiniteDuration,
override val supervisorStrategy: SupervisorStrategy = Pool.defaultSupervisorStrategy,
override val routerDispatcher: String = Dispatchers.DefaultDispatcherId,
override val usePoolDispatcher: Boolean = false)
extends Pool
with PoolOverrideUnsetConfig[ScatterGatherFirstCompletedPool] {
def this(config: Config) =
this(
nrOfInstances = config.getInt("nr-of-instances"),
within = config.getMillisDuration("within"),
resizer = Resizer.fromConfig(config),
usePoolDispatcher = config.hasPath("pool-dispatcher"))
/**
* Java API
* @param nr initial number of routees in the pool
* @param within expecting at least one reply within this duration, otherwise
* it will reply with [[akka.pattern.AskTimeoutException]] in a [[akka.actor.Status.Failure]]
*/
def this(nr: Int, within: FiniteDuration) = this(nrOfInstances = nr, within = within)
/**
* Java API
* @param nr initial number of routees in the pool
* @param within expecting at least one reply within this duration, otherwise
* it will reply with [[akka.pattern.AskTimeoutException]] in a [[akka.actor.Status.Failure]]
*/
def this(nr: Int, within: java.time.Duration) = this(nr, within.asScala)
override def createRouter(system: ActorSystem): Router = new Router(ScatterGatherFirstCompletedRoutingLogic(within))
override def nrOfInstances(sys: ActorSystem) = this.nrOfInstances
/**
* Setting the supervisor strategy to be used for the “head” Router actor.
*/
def withSupervisorStrategy(strategy: SupervisorStrategy): ScatterGatherFirstCompletedPool =
copy(supervisorStrategy = strategy)
/**
* Setting the resizer to be used.
*/
def withResizer(resizer: Resizer): ScatterGatherFirstCompletedPool = copy(resizer = Some(resizer))
/**
* Setting the dispatcher to be used for the router head actor, which handles
* supervision, death watch and router management messages.
*/
def withDispatcher(dispatcherId: String): ScatterGatherFirstCompletedPool = copy(routerDispatcher = dispatcherId)
/**
* Uses the resizer and/or the supervisor strategy of the given RouterConfig
* if this RouterConfig doesn't have one, i.e. the resizer defined in code is used if
* resizer was not defined in config.
*/
override def withFallback(other: RouterConfig): RouterConfig = this.overrideUnsetConfig(other)
}
/**
* A router group that broadcasts the message to all routees, and replies with the first response.
*
* The configuration parameter trumps the constructor arguments. This means that
* if you provide `paths` during instantiation they will be ignored if
* the router is defined in the configuration file for the actor being used.
*
* @param paths string representation of the actor paths of the routees, messages are
* sent with [[akka.actor.ActorSelection]] to these paths
*
* @param within expecting at least one reply within this duration, otherwise
* it will reply with [[akka.pattern.AskTimeoutException]] in a [[akka.actor.Status.Failure]]
*
* @param routerDispatcher dispatcher to use for the router head actor, which handles
* router management messages
*/
@SerialVersionUID(1L)
final case class ScatterGatherFirstCompletedGroup(
paths: immutable.Iterable[String],
within: FiniteDuration,
override val routerDispatcher: String = Dispatchers.DefaultDispatcherId)
extends Group {
def this(config: Config) =
this(paths = immutableSeq(config.getStringList("routees.paths")), within = config.getMillisDuration("within"))
/**
* Java API
* @param routeePaths string representation of the actor paths of the routees, messages are
* sent with [[akka.actor.ActorSelection]] to these paths
* @param within expecting at least one reply within this duration, otherwise
* it will reply with [[akka.pattern.AskTimeoutException]] in a [[akka.actor.Status.Failure]]
*/
def this(routeePaths: java.lang.Iterable[String], within: FiniteDuration) =
this(paths = immutableSeq(routeePaths), within = within)
/**
* Java API
* @param routeePaths string representation of the actor paths of the routees, messages are
* sent with [[akka.actor.ActorSelection]] to these paths
* @param within expecting at least one reply within this duration, otherwise
* it will reply with [[akka.pattern.AskTimeoutException]] in a [[akka.actor.Status.Failure]]
*/
def this(routeePaths: java.lang.Iterable[String], within: java.time.Duration) =
this(immutableSeq(routeePaths), within.asScala)
override def paths(system: ActorSystem): immutable.Iterable[String] = this.paths
override def createRouter(system: ActorSystem): Router = new Router(ScatterGatherFirstCompletedRoutingLogic(within))
/**
* Setting the dispatcher to be used for the router head actor, which handles
* router management messages
*/
def withDispatcher(dispatcherId: String): ScatterGatherFirstCompletedGroup = copy(routerDispatcher = dispatcherId)
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy