1 files changed, 61 insertions, 0 deletions
diff --git a/kamon-akka/src/main/scala/kamon/akka/instrumentation/RouterMonitor.scala b/kamon-akka/src/main/scala/kamon/akka/instrumentation/RouterMonitor.scala
new file mode 100644
index 00000000..5c4c7aa3
--- /dev/null
+++ b/kamon-akka/src/main/scala/kamon/akka/instrumentation/RouterMonitor.scala
@@ -0,0 +1,61 @@
+package akka.kamon.instrumentation
+
+import akka.actor.{ Cell, Props, ActorRef, ActorSystem }
+import akka.dispatch.{ Envelope, MessageDispatcher }
+import akka.routing.RoutedActorCell
+import kamon.Kamon
+import kamon.akka.RouterMetrics
+import kamon.metric.Entity
+import kamon.util.RelativeNanoTimestamp
+import org.aspectj.lang.ProceedingJoinPoint
+import org.aspectj.lang.annotation._
+
+trait RouterMonitor {
+  def processMessage(pjp: ProceedingJoinPoint): AnyRef
+  def processFailure(failure: Throwable): Unit
+  def cleanup(): Unit
+
+  def routeeAdded(): Unit
+  def routeeRemoved(): Unit
+}
+
+object RouterMonitor {
+
+  def createRouterInstrumentation(cell: Cell): RouterMonitor = {
+    val cellInfo = CellInfo.cellInfoFor(cell, cell.system, cell.self, cell.parent)
+    def routerMetrics = Kamon.metrics.entity(RouterMetrics, cellInfo.entity)
+
+    if (cellInfo.isTracked)
+      new MetricsOnlyRouterMonitor(cellInfo.entity, routerMetrics)
+    else NoOpRouterMonitor
+  }
+}
+
+object NoOpRouterMonitor extends RouterMonitor {
+  def processMessage(pjp: ProceedingJoinPoint): AnyRef = pjp.proceed()
+  def processFailure(failure: Throwable): Unit = {}
+  def routeeAdded(): Unit = {}
+  def routeeRemoved(): Unit = {}
+  def cleanup(): Unit = {}
+}
+
+class MetricsOnlyRouterMonitor(entity: Entity, routerMetrics: RouterMetrics) extends RouterMonitor {
+
+  def processMessage(pjp: ProceedingJoinPoint): AnyRef = {
+    val timestampBeforeProcessing = RelativeNanoTimestamp.now
+
+    try {
+      pjp.proceed()
+    } finally {
+      val timestampAfterProcessing = RelativeNanoTimestamp.now
+      val routingTime = timestampAfterProcessing - timestampBeforeProcessing
+
+      routerMetrics.routingTime.record(routingTime.nanos)
+    }
+  }
+
+  def processFailure(failure: Throwable): Unit = {}
+  def routeeAdded(): Unit = {}
+  def routeeRemoved(): Unit = {}
+  def cleanup(): Unit = Kamon.metrics.removeEntity(entity)
+}
+\ No newline at end of file