= core: first simple approach to providing traces and a subscription mechanism.

1 files changed, 29 insertions, 0 deletions

diff --git a/kamon-core/src/main/scala/kamon/trace/TraceSubscriptions.scala b/kamon-core/src/main/scala/kamon/trace/TraceSubscriptions.scala
new file mode 100644
index 00000000..d533a344
--- /dev/null
+++ b/kamon-core/src/main/scala/kamon/trace/TraceSubscriptions.scala
@@ -0,0 +1,29 @@
+package kamon.trace
+
+import akka.actor.{ Terminated, ActorRef, Actor }
+
+class TraceSubscriptions extends Actor {
+  import TraceSubscriptions._
+
+  var subscribers: List[ActorRef] = Nil
+
+  def receive = {
+    case Subscribe(newSubscriber) ⇒
+      if (!subscribers.contains(newSubscriber))
+        subscribers = context.watch(newSubscriber) :: subscribers
+
+    case Unsubscribe(leavingSubscriber) ⇒
+      subscribers = subscribers.filter(_ == leavingSubscriber)
+
+    case Terminated(terminatedSubscriber) ⇒
+      subscribers = subscribers.filter(_ == terminatedSubscriber)
+
+    case trace: TraceInfo ⇒
+      subscribers.foreach(_ ! trace)
+  }
+}
+
+object TraceSubscriptions {
+  case class Subscribe(subscriber: ActorRef)
+  case class Unsubscribe(subscriber: ActorRef)
+}