1 files changed, 44 insertions, 2 deletions
diff --git a/kamon-core/src/main/scala/kamon/metrics/Subscriptions.scala b/kamon-core/src/main/scala/kamon/metrics/Subscriptions.scala
index 654c37b0..2111563b 100644
--- a/kamon-core/src/main/scala/kamon/metrics/Subscriptions.scala
+++ b/kamon-core/src/main/scala/kamon/metrics/Subscriptions.scala
@@ -16,12 +16,13 @@
 
 package kamon.metrics
 
-import akka.actor.{ ActorRef, Actor }
+import akka.actor.{Props, ActorRef, Actor}
 import kamon.metrics.Subscriptions.{ MetricGroupFilter, FlushMetrics, TickMetricSnapshot, Subscribe }
 import kamon.util.GlobPathFilter
-import scala.concurrent.duration.Duration
+import scala.concurrent.duration.{FiniteDuration, Duration}
 import java.util.concurrent.TimeUnit
 import kamon.Kamon
+import kamon.metrics.TickMetricSnapshotBuffer.FlushBuffer
 
 class Subscriptions extends Actor {
   import context.system
@@ -85,5 +86,46 @@ object Subscriptions {
       category.equals(identity.category) && globFilter.accept(identity.name)
     }
   }
+}
+
+
+class TickMetricSnapshotBuffer(flushInterval: FiniteDuration, receiver: ActorRef) extends Actor {
+  val flushSchedule = context.system.scheduler.schedule(flushInterval, flushInterval, self, FlushBuffer)(context.dispatcher)
+
+  def receive = empty
+
+  def empty: Actor.Receive = {
+    case tick : TickMetricSnapshot  => context become(buffering(tick))
+    case FlushBuffer                => // Nothing to flush.
+  }
+
+  def buffering(buffered: TickMetricSnapshot): Actor.Receive = {
+    case TickMetricSnapshot(_, to, tickMetrics) =>
+      val combinedMetrics = combineMaps(buffered.metrics, tickMetrics)(mergeMetricGroup)
+      val combinedSnapshot = TickMetricSnapshot(buffered.from, to, combinedMetrics)
+
+      context become(buffering(combinedSnapshot))
+
+    case FlushBuffer =>
+      receiver ! buffered
+      context become(empty)
+
+  }
+
+
+  override def postStop(): Unit = {
+    flushSchedule.cancel()
+    super.postStop()
+  }
+
+  def mergeMetricGroup(left: MetricGroupSnapshot, right: MetricGroupSnapshot) = new MetricGroupSnapshot {
+    val metrics = combineMaps(left.metrics, right.metrics)((l, r) => l.merge(r))
+  }
+}
+
+object TickMetricSnapshotBuffer {
+  case object FlushBuffer
 
+  def props(flushInterval: FiniteDuration, receiver: ActorRef): Props =
+    Props[TickMetricSnapshotBuffer](new TickMetricSnapshotBuffer(flushInterval, receiver))
 }