+ newrelic: add possibility to send akka metrics to the newrelic

Added possibility to send akka metrics to the newrelic as custom metrics.
Externalized categories of newrelic subscription into the configuration file.
This allow to define which metrics categories should be send to newrelic
independent upon which metrics are actually collected.

Akka metrics exported to the newrelic as custom metrics and available in custom
dashboards in some format similar to:

Cusom/akka-actor/{ActorSystemName[user|system|...]\{ActorName}/{MetricName}

for actors and

Custom/akka-thread-pool-executor\Some-Service\akka.io.pinned-dispatcher/ProcessedTasks

for thread pools.

Same metrics for multiple actors can be displayed as a single chart by using *
(star) for part of the actor name. For example

Cusom/akka-actor\MyActor\user\*DatabaseWorker/ProcessingTime

will show processing time for all database workers.

Example of actor metrics displayed by newrelic:
http://s4.postimg.org/sfn9vjzgt/Screen_Shot_2015_04_22_at_11_24_15.png

Example of pool metrics displayed by newrelic:
http://s4.postimg.org/gchy7zoel/Screen_Shot_2015_04_22_at_11_24_24.png

1 files changed, 62 insertions, 5 deletions

diff --git a/kamon-newrelic/src/main/scala/kamon/newrelic/Agent.scala b/kamon-newrelic/src/main/scala/kamon/newrelic/Agent.scala
index 75f73ea4..3e43da36 100644
--- a/kamon-newrelic/src/main/scala/kamon/newrelic/Agent.scala
+++ b/kamon-newrelic/src/main/scala/kamon/newrelic/Agent.scala
@@ -16,10 +16,13 @@
 
 package kamon.newrelic
 
-import akka.actor.{ ActorLogging, Actor }
+import akka.actor.{ ActorRef, ActorLogging, Actor }
+import akka.event.LoggingAdapter
 import akka.io.IO
 import akka.util.Timeout
 import com.typesafe.config.Config
+import kamon.Kamon
+import kamon.metric.{ SegmentMetrics, TraceMetrics, MetricsModule, TickMetricSnapshotBuffer }
 import spray.can.Http
 import spray.json._
 import scala.concurrent.Future
@@ -30,16 +33,28 @@ import kamon.util.ConfigTools.Syntax
 import Agent._
 import JsonProtocol._
 import akka.pattern.pipe
-
+import scala.concurrent.duration._
 import scala.concurrent.duration.FiniteDuration
 
-class Agent extends Actor with SprayJsonSupport with ActorLogging {
+class Agent extends Actor with SprayJsonSupport with ActorLogging with MetricsSubscription {
   import context.dispatcher
 
-  val agentSettings = AgentSettings.fromConfig(context.system.settings.config)
+  private val config = context.system.settings.config
+
+  val agentSettings = AgentSettings.fromConfig(config)
 
   // Start the reporters
-  context.actorOf(MetricReporter.props(agentSettings), "metric-reporter")
+  private val reporter = context.actorOf(MetricReporter.props(agentSettings), "metric-reporter")
+
+  val metricsSubscriber = {
+    val tickInterval = Kamon.metrics.settings.tickInterval
+
+    // Metrics are always sent to New Relic in 60 seconds intervals.
+    if (tickInterval == 60.seconds) reporter
+    else context.actorOf(TickMetricSnapshotBuffer.props(1 minute, reporter), "metric-buffer")
+  }
+
+  subscribeToMetrics(config, metricsSubscriber, Kamon.metrics)
 
   // Start the connection to the New Relic collector.
   self ! Connect
@@ -143,4 +158,46 @@ object AgentSettings {
       newRelicConfig.getFiniteDuration("connect-retry-delay"),
       newRelicConfig.getFiniteDuration("apdexT").toMillis / 1E3D)
   }
+}
+
+trait MetricsSubscription {
+  import kamon.util.ConfigTools.Syntax
+  import scala.collection.JavaConverters._
+  import MetricsSubscription._
+
+  def log: LoggingAdapter
+
+  def subscriptions(config: Config) = config getConfig "kamon.newrelic" getConfig "custom-metric-subscriptions"
+
+  def subscriptionKeys(config: Config) = subscriptions(config).firstLevelKeys filterNot isTraceOrSegmentEntityName
+
+  def subscribeToMetrics(config: Config, metricsSubscriber: ActorRef, extension: MetricsModule): Unit = {
+    subscribeToCustomMetrics(config, metricsSubscriber, extension)
+    subscribeToTransactionMetrics(metricsSubscriber, extension)
+  }
+
+  def subscribeToCustomMetrics(config: Config, metricsSubscriber: ActorRef, extension: MetricsModule): Unit =
+    subscriptionKeys(config) foreach { subscriptionCategory ⇒
+      subscriptions(config).getStringList(subscriptionCategory).asScala foreach { pattern ⇒
+        log.debug("Subscribing NewRelic reporting for custom metric '{}' : {}", subscriptionCategory, pattern)
+        extension.subscribe(subscriptionCategory, pattern, metricsSubscriber)
+      }
+    }
+
+  def subscribeToTransactionMetrics(metricsSubscriber: ActorRef, extension: MetricsModule): Unit =
+    traceAndSegmentMetrics foreach { subscriptionCategory ⇒
+      log.debug("Subscribing NewRelic reporting for transaction metric '{}' : {}", subscriptionCategory, defaultPattern)
+      extension.subscribe(subscriptionCategory, defaultPattern, metricsSubscriber)
+    }
+
+}
+
+object MetricsSubscription {
+
+  private val defaultPattern = "**"
+
+  private val traceAndSegmentMetrics = Seq(TraceMetrics.category, SegmentMetrics.category)
+
+  def isTraceOrSegmentEntityName(name: String): Boolean = traceAndSegmentMetrics contains name
+
 }
\ No newline at end of file