! all: improve the metric recorders infrastructure

1 files changed, 48 insertions, 0 deletions

diff --git a/kamon-core/src/main/scala/kamon/ModuleSupervisor.scala b/kamon-core/src/main/scala/kamon/ModuleSupervisor.scala
new file mode 100644
index 00000000..99d87719
--- /dev/null
+++ b/kamon-core/src/main/scala/kamon/ModuleSupervisor.scala
@@ -0,0 +1,48 @@
+package kamon
+
+import _root_.akka.actor
+import _root_.akka.actor._
+import kamon.ModuleSupervisor.CreateModule
+
+import scala.concurrent.{ Future, Promise }
+import scala.util.Success
+
+object ModuleSupervisor extends ExtensionId[ModuleSupervisorExtension] with ExtensionIdProvider {
+
+  def lookup(): ExtensionId[_ <: actor.Extension] = ModuleSupervisor
+  def createExtension(system: ExtendedActorSystem): ModuleSupervisorExtension = new ModuleSupervisorExtensionImpl(system)
+
+  case class CreateModule(name: String, props: Props, childPromise: Promise[ActorRef])
+}
+
+trait ModuleSupervisorExtension extends actor.Extension {
+  def createModule(name: String, props: Props): Future[ActorRef]
+}
+
+class ModuleSupervisorExtensionImpl(system: ExtendedActorSystem) extends ModuleSupervisorExtension {
+  import system.dispatcher
+  private lazy val supervisor = system.actorOf(Props[ModuleSupervisor], "kamon")
+
+  def createModule(name: String, props: Props): Future[ActorRef] = Future {} flatMap { _: Unit ⇒
+    val modulePromise = Promise[ActorRef]()
+    supervisor ! CreateModule(name, props, modulePromise)
+    modulePromise.future
+  }
+}
+
+class ModuleSupervisor extends Actor with ActorLogging {
+
+  def receive = {
+    case CreateModule(name, props, childPromise) ⇒ createChildModule(name, props, childPromise)
+  }
+
+  def createChildModule(name: String, props: Props, childPromise: Promise[ActorRef]): Unit = {
+    context.child(name).map { alreadyAvailableModule ⇒
+      log.warning("Received a request to create module [{}] but the module is already available, returning the existent one.")
+      childPromise.complete(Success(alreadyAvailableModule))
+
+    } getOrElse {
+      childPromise.complete(Success(context.actorOf(props, name)))
+    }
+  }
+}