Failed commands in SelectionHandler are now notified in a nicer way.

akka-actor-tests/src/test/scala/akka/io/TcpListenerSpec.scala

@@ -20,7 +20,7 @@ class TcpListenerSpec extends AkkaSpec("akka.io.tcp.batch-accept-limit = 2") {
     "register its ServerSocketChannel with its selector" in new TestSetup
 
     "let the Bind commander know when binding is completed" in new TestSetup {
-      listener ! KickStartDone
+      listener ! WorkerForCommandDone
       bindCommander.expectMsg(Bound)
     }
 
@@ -36,13 +36,13 @@ class TcpListenerSpec extends AkkaSpec("akka.io.tcp.batch-accept-limit = 2") {
 
       parent.expectMsg(AcceptInterest)
       // FIXME: ugly stuff here
-      selectorRouter.expectMsgType[KickStartCommand]
-      selectorRouter.expectMsgType[KickStartCommand]
+      selectorRouter.expectMsgType[WorkerForCommand]
+      selectorRouter.expectMsgType[WorkerForCommand]
       selectorRouter.expectNoMsg(100.millis)
 
       // and pick up the last remaining connection on the next ChannelAcceptable
       listener ! ChannelAcceptable
-      selectorRouter.expectMsgType[KickStartCommand]
+      selectorRouter.expectMsgType[WorkerForCommand]
     }
 
     "react to Unbind commands by replying with Unbound and stopping itself" in new TestSetup {
@@ -61,7 +61,7 @@ class TcpListenerSpec extends AkkaSpec("akka.io.tcp.batch-accept-limit = 2") {
       attemptConnectionToEndpoint()
 
       listener ! ChannelAcceptable
-      val props = selectorRouter.expectMsgType[KickStartCommand].childProps
+      val props = selectorRouter.expectMsgType[WorkerForCommand].childProps
       // FIXME: need to instantiate propss
       //selectorRouter.expectMsgType[RegisterChannel].channel.isOpen must be(true)
 
@@ -87,7 +87,7 @@ class TcpListenerSpec extends AkkaSpec("akka.io.tcp.batch-accept-limit = 2") {
     parent.expectMsgType[RegisterChannel]
 
     def bindListener() {
-      listener ! KickStartDone
+      listener ! WorkerForCommandDone
       bindCommander.expectMsg(Bound)
     }
 

akka-actor/src/main/scala/akka/io/IO.scala

@@ -6,7 +6,7 @@ package akka.io
 
 import akka.actor._
 import akka.routing.RandomRouter
-import akka.io.SelectionHandler.KickStartCommand
+import akka.io.SelectionHandler.WorkerForCommand
 
 object IO {
 
@@ -16,22 +16,25 @@ object IO {
 
   def apply[T <: Extension](key: ExtensionKey[T])(implicit system: ActorSystem): ActorRef = key(system).manager
 
+  trait HasFailureMessage {
+    def failureMessage: Any
+  }
+
   abstract class SelectorBasedManager(selectorSettings: SelectionHandlerSettings, nrOfSelectors: Int) extends Actor {
 
     val selectorPool = context.actorOf(
       props = Props(new SelectionHandler(self, selectorSettings)).withRouter(RandomRouter(nrOfSelectors)),
       name = "selectors")
 
-    def createKickStart(pf: PartialFunction[Any, Props], cmd: Any): PartialFunction[Any, KickStartCommand] = {
-      pf.andThen { props ⇒
+    private def createKickStart(pf: PartialFunction[HasFailureMessage, Props]): PartialFunction[HasFailureMessage, WorkerForCommand] = {
+      case cmd ⇒
+        val props = pf(cmd)
         val commander = sender
-        KickStartCommand(cmd, commander, props)
-      }
+        WorkerForCommand(cmd, commander, props)
     }
 
     def kickStartReceive(pf: PartialFunction[Any, Props]): Receive = {
-      //case KickStartFailed =
-      case cmd if pf.isDefinedAt(cmd) ⇒ selectorPool ! createKickStart(pf, cmd)(cmd)
+      case cmd: HasFailureMessage if pf.isDefinedAt(cmd) ⇒ selectorPool ! createKickStart(pf)(cmd)
     }
   }
 

akka-actor/src/main/scala/akka/io/SelectionHandler.scala

@@ -14,6 +14,7 @@ import scala.concurrent.duration._
 import akka.actor._
 import com.typesafe.config.Config
 import akka.actor.Terminated
+import akka.io.IO.HasFailureMessage
 
 abstract class SelectionHandlerSettings(config: Config) {
   import config._
@@ -42,14 +43,12 @@ abstract class SelectionHandlerSettings(config: Config) {
 
 private[io] object SelectionHandler {
 
-  //FIXME: temporary
-  case class KickStartCommand(apiCommand: Any, commander: ActorRef, childProps: Props)
+  case class WorkerForCommand(apiCommand: HasFailureMessage, commander: ActorRef, childProps: Props)
   // FIXME: all actors should listen to this
-  case object KickStartDone
-  case class KickStartFailed(apiCommand: Any, commander: ActorRef)
+  case object WorkerForCommandDone
 
   case class RegisterChannel(channel: SelectableChannel, initialOps: Int)
-  case class Retry(command: KickStartCommand, retriesLeft: Int) { require(retriesLeft >= 0) }
+  case class Retry(command: WorkerForCommand, retriesLeft: Int) { require(retriesLeft >= 0) }
 
   case object ChannelConnectable
   case object ChannelAcceptable
@@ -75,21 +74,21 @@ private[io] class SelectionHandler(manager: ActorRef, settings: SelectionHandler
     case ReadInterest   ⇒ execute(enableInterest(OP_READ, sender))
     case AcceptInterest ⇒ execute(enableInterest(OP_ACCEPT, sender))
 
+    // FIXME: provide StopReading functionality
     //case StopReading    ⇒ execute(disableInterest(OP_READ, sender))
 
-    case cmd: KickStartCommand ⇒
+    case cmd: WorkerForCommand ⇒
       // FIXME: factor out to common
-      withCapacityProtection(cmd, SelectorAssociationRetries) { spawnChild(cmd.childProps) ! KickStartDone }
+      withCapacityProtection(cmd, SelectorAssociationRetries) { spawnChild(cmd.childProps) ! WorkerForCommandDone }
 
     case RegisterChannel(channel, initialOps) ⇒
       execute(registerChannel(channel, sender, initialOps))
 
-    case Retry(cmd, 0) ⇒
-      // FIXME: extractors
-      manager ! KickStartFailed(cmd.apiCommand, cmd.commander)
+    case Retry(WorkerForCommand(cmd, commander, _), 0) ⇒
+      commander ! cmd.failureMessage
 
     case Retry(cmd, retriesLeft) ⇒
-      withCapacityProtection(cmd, retriesLeft) { spawnChild(cmd.childProps) ! KickStartDone }
+      withCapacityProtection(cmd, retriesLeft) { spawnChild(cmd.childProps) ! WorkerForCommandDone }
 
     case Terminated(child) ⇒
       execute(unregister(child))
@@ -114,7 +113,7 @@ private[io] class SelectionHandler(manager: ActorRef, settings: SelectionHandler
   // we can never recover from failures of a connection or listener child
   override def supervisorStrategy = SupervisorStrategy.stoppingStrategy
 
-  def withCapacityProtection(cmd: KickStartCommand, retriesLeft: Int)(body: ⇒ Unit): Unit = {
+  def withCapacityProtection(cmd: WorkerForCommand, retriesLeft: Int)(body: ⇒ Unit): Unit = {
     log.debug("Executing {}", cmd)
     if (MaxChannelsPerSelector == -1 || childrenKeys.size < MaxChannelsPerSelector) {
       body

akka-actor/src/main/scala/akka/io/Tcp.scala

@@ -6,7 +6,7 @@ package akka.io
 
 import java.net.InetSocketAddress
 import java.net.Socket
-import akka.io.Inet.SocketOption
+import akka.io.Inet._
 import com.typesafe.config.Config
 import scala.concurrent.duration._
 import scala.collection.immutable
@@ -58,7 +58,9 @@ object Tcp extends ExtensionKey[TcpExt] {
   }
 
   /// COMMANDS
-  trait Command
+  trait Command extends IO.HasFailureMessage {
+    def failureMessage = CommandFailed(this)
+  }
 
   case class Connect(remoteAddress: InetSocketAddress,
                      localAddress: Option[InetSocketAddress] = None,

akka-actor/src/main/scala/akka/io/TcpListener.scala

@@ -5,7 +5,7 @@
 package akka.io
 
 import java.net.InetSocketAddress
-import java.nio.channels.{ SelectionKey, ServerSocketChannel }
+import java.nio.channels.{ SocketChannel, SelectionKey, ServerSocketChannel }
 import scala.annotation.tailrec
 import scala.collection.immutable
 import scala.util.control.NonFatal
@@ -13,6 +13,17 @@ import akka.actor.{ Props, ActorLogging, ActorRef, Actor }
 import akka.io.SelectionHandler._
 import akka.io.Inet.SocketOption
 import akka.io.Tcp._
+import akka.io.IO.HasFailureMessage
+
+private[io] object TcpListener {
+
+  case class RegisterIncoming(channel: SocketChannel) extends HasFailureMessage {
+    def failureMessage = FailedRegisterIncoming(channel)
+  }
+
+  case class FailedRegisterIncoming(channel: SocketChannel)
+
+}
 
 private[io] class TcpListener(selectorRouter: ActorRef,
                               handler: ActorRef,
@@ -23,6 +34,7 @@ private[io] class TcpListener(selectorRouter: ActorRef,
                               options: immutable.Traversable[SocketOption]) extends Actor with ActorLogging {
 
   def selector: ActorRef = context.parent
+  import TcpListener._
   import tcp.Settings._
 
   context.watch(handler) // sign death pact
@@ -38,7 +50,7 @@ private[io] class TcpListener(selectorRouter: ActorRef,
   log.debug("Successfully bound to {}", endpoint)
 
   def receive: Receive = {
-    case KickStartDone ⇒
+    case WorkerForCommandDone ⇒
       bindCommander ! Bound
       context.become(bound)
   }
@@ -47,12 +59,12 @@ private[io] class TcpListener(selectorRouter: ActorRef,
     case ChannelAcceptable ⇒
       acceptAllPending(BatchAcceptLimit)
 
-    //    case CommandFailed(RegisterIncomingConnection(socketChannel, _, _)) ⇒
-    //      log.warning("Could not register incoming connection since selector capacity limit is reached, closing connection")
-    //      try socketChannel.close()
-    //      catch {
-    //        case NonFatal(e) ⇒ log.error(e, "Error closing channel")
-    //      }
+    case FailedRegisterIncoming(socketChannel) ⇒
+      log.warning("Could not register incoming connection since selector capacity limit is reached, closing connection")
+      try socketChannel.close()
+      catch {
+        case NonFatal(e) ⇒ log.error(e, "Error closing channel")
+      }
 
     case Unbind ⇒
       log.debug("Unbinding endpoint {}", endpoint)
@@ -72,9 +84,7 @@ private[io] class TcpListener(selectorRouter: ActorRef,
       if (socketChannel != null) {
         log.debug("New connection accepted")
         socketChannel.configureBlocking(false)
-        //selectorRouter ! RegisterIncomingConnection(socketChannel, handler, options)
-        // FIXME null is not nice. There is no explicit API command here
-        selectorRouter ! KickStartCommand(null, context.system.deadLetters, Props(new TcpIncomingConnection(socketChannel, tcp, handler, options)))
+        selectorRouter ! WorkerForCommand(RegisterIncoming(socketChannel), self, Props(new TcpIncomingConnection(socketChannel, tcp, handler, options)))
         acceptAllPending(limit - 1)
       }
     } else context.parent ! AcceptInterest

akka-actor/src/main/scala/akka/io/TcpManager.scala

@@ -4,10 +4,8 @@
 
 package akka.io
 
-import akka.actor.{ ActorLogging, Actor, Props }
-import akka.routing.RandomRouter
 import Tcp._
-import akka.io.SelectionHandler.{ KickStartFailed, KickStartCommand }
+import akka.actor.{ ActorLogging, Props }
 import akka.io.IO.SelectorBasedManager
 
 /**

akka-actor/src/main/scala/akka/io/UdpFF.scala

@@ -15,7 +15,9 @@ object UdpFF extends ExtensionKey[UdpFFExt] {
   // Java API
   override def get(system: ActorSystem): UdpFFExt = system.extension(this)
 
-  trait Command
+  trait Command extends IO.HasFailureMessage {
+    def failureMessage = CommandFailed(this)
+  }
 
   case object NoAck
   case class Send(payload: ByteString, target: InetSocketAddress, ack: Any) extends Command {

akka-actor/src/main/scala/akka/io/UdpFFManager.scala

@@ -3,11 +3,9 @@
  */
 package akka.io
 
-import akka.actor.{ ActorRef, Props, Actor }
-import akka.io.UdpFF._
-import akka.routing.RandomRouter
-import akka.io.SelectionHandler.{ KickStartFailed, KickStartCommand }
+import akka.actor.{ ActorRef, Props }
 import akka.io.IO.SelectorBasedManager
+import akka.io.UdpFF._
 
 /**
  * UdpFFManager is a facade for simple fire-and-forget style UDP operations