+ datadog: allow time and memory metrics be scaled before sending to datadog

2 files changed, 21 insertions, 2 deletions

diff --git a/kamon-datadog/src/main/resources/reference.conf b/kamon-datadog/src/main/resources/reference.conf
index 7da8e645..78b58a6e 100644
--- a/kamon-datadog/src/main/resources/reference.conf
+++ b/kamon-datadog/src/main/resources/reference.conf
@@ -37,6 +37,16 @@ kamon {
     # this pattern:
     #    application.entity-name.metric-name
     application-name = "kamon"
+
+    # All time values are collected in nanoseconds,
+    # to scale before sending to datadog set "time-units" to "s" or "ms" or "µs".
+    # Value "ns" is equivalent to omitting the setting
+    # time-units = "ns"
+
+    # All memory values are collected in bytes,
+    # to scale before sending to datadog set "memory-units" to "gb" or "mb" or "kb".
+    # Value "b" is equivalent to omitting the setting
+    # memory-units = "b"
   }
 
   modules {
diff --git a/kamon-datadog/src/main/scala/kamon/datadog/Datadog.scala b/kamon-datadog/src/main/scala/kamon/datadog/Datadog.scala
index ab909055..cde80531 100644
--- a/kamon-datadog/src/main/scala/kamon/datadog/Datadog.scala
+++ b/kamon-datadog/src/main/scala/kamon/datadog/Datadog.scala
@@ -27,6 +27,8 @@ import kamon.metric._
 import scala.collection.JavaConverters._
 import scala.concurrent.duration._
 
+import kamon.util.NeedToScale
+
 object Datadog extends ExtensionId[DatadogExtension] with ExtensionIdProvider {
   override def lookup(): ExtensionId[_ <: Extension] = Datadog
   override def createExtension(system: ExtendedActorSystem): DatadogExtension = new DatadogExtension(system)
@@ -57,11 +59,18 @@ class DatadogExtension(system: ExtendedActorSystem) extends Kamon.Extension {
     assert(flushInterval >= tickInterval, "Datadog flush-interval needs to be equal or greater to the tick-interval")
 
     val metricsSender = system.actorOf(DatadogMetricsSender.props(datadogHost, maxPacketSizeInBytes), "datadog-metrics-sender")
+
+    val decoratedSender = datadogConfig match {
+      case NeedToScale(scaleTimeTo, scaleMemoryTo) =>
+        system.actorOf(MetricScaleDecorator.props(scaleTimeTo, scaleMemoryTo, metricsSender), "datadog-metric-scale-decorator")
+      case _ => metricsSender
+    }
+
     if (flushInterval == tickInterval) {
       // No need to buffer the metrics, let's go straight to the metrics sender.
-      metricsSender
+      decoratedSender
     } else {
-      system.actorOf(TickMetricSnapshotBuffer.props(flushInterval, metricsSender), "datadog-metrics-buffer")
+      system.actorOf(TickMetricSnapshotBuffer.props(flushInterval, decoratedSender), "datadog-metrics-buffer")
     }
   }
 }