Merge branch 'master' into release-0.2

Conflicts:
	kamon-play/src/test/scala/kamon/play/WSInstrumentationSpec.scala
	kamon-statsd/src/main/scala/kamon/statsd/StatsD.scala
	project/Dependencies.scala
	project/Projects.scala
	version.sbt

4 files changed, 57 insertions, 42 deletions

diff --git a/kamon-statsd/src/main/resources/reference.conf b/kamon-statsd/src/main/resources/reference.conf
index f648b7af..fd6293d9 100644
--- a/kamon-statsd/src/main/resources/reference.conf
+++ b/kamon-statsd/src/main/resources/reference.conf
@@ -13,14 +13,15 @@ kamon {
     # kamon.metrics.tick-interval setting.
     flush-interval = 1 second
 
-    # Max packet size in bytes for UDP metrics data sent to StatsD.
-    max-packet-size = 1024
+    # Max packet size for UDP metrics data sent to StatsD.
+    max-packet-size = 1024 bytes
 
     # Subscription patterns used to select which metrics will be pushed to StatsD. Note that first, metrics
     # collection for your desired entities must be activated under the kamon.metrics.filters settings.
     includes {
-      actor = [ "*" ]
-      trace = [ "*" ]
+      actor      =  [ "*" ]
+      trace      =  [ "*" ]
+      dispatcher =  [ "*" ]
     }
 
     simple-metric-key-generator {
diff --git a/kamon-statsd/src/main/scala/kamon/statsd/StatsD.scala b/kamon-statsd/src/main/scala/kamon/statsd/StatsD.scala
index 7676f97f..f10406ed 100644
--- a/kamon-statsd/src/main/scala/kamon/statsd/StatsD.scala
+++ b/kamon-statsd/src/main/scala/kamon/statsd/StatsD.scala
@@ -60,6 +60,12 @@ class StatsDExtension(system: ExtendedActorSystem) extends Kamon.Extension {
     Kamon(Metrics)(system).subscribe(TraceMetrics, tracePathPattern, statsDMetricsListener, permanently = true)
   }
 
+  // Subscribe to Dispatchers
+  val includedDispatchers = statsDConfig.getStringList("includes.dispatcher").asScala
+  for (dispatcherPathPattern ← includedDispatchers) {
+    Kamon(Metrics)(system).subscribe(DispatcherMetrics, dispatcherPathPattern, statsDMetricsListener, permanently = true)
+  }
+
   def buildMetricsListener(tickInterval: Long, flushInterval: Long): ActorRef = {
     assert(flushInterval >= tickInterval, "StatsD flush-interval needs to be equal or greater to the tick-interval")
 
diff --git a/kamon-statsd/src/main/scala/kamon/statsd/StatsDMetricsSender.scala b/kamon-statsd/src/main/scala/kamon/statsd/StatsDMetricsSender.scala
index cff970b4..adda18cc 100644
--- a/kamon-statsd/src/main/scala/kamon/statsd/StatsDMetricsSender.scala
+++ b/kamon-statsd/src/main/scala/kamon/statsd/StatsDMetricsSender.scala
@@ -20,18 +20,21 @@ import akka.actor.{ ActorSystem, Props, ActorRef, Actor }
 import akka.io.{ Udp, IO }
 import java.net.InetSocketAddress
 import akka.util.ByteString
-import kamon.Kamon
 import kamon.metrics.Subscriptions.TickMetricSnapshot
 import kamon.metrics.MetricSnapshot.Measurement
 import kamon.metrics.InstrumentTypes.{ Counter, Gauge, Histogram, InstrumentType }
-import java.text.DecimalFormat
+import java.text.{ DecimalFormatSymbols, DecimalFormat }
+import java.util.Locale
 
-class StatsDMetricsSender(remote: InetSocketAddress, maxPacketSize: Int) extends Actor with UdpExtensionProvider {
+class StatsDMetricsSender(remote: InetSocketAddress, maxPacketSizeInBytes: Long) extends Actor with UdpExtensionProvider {
   import context.system
 
   val metricKeyGenerator = new SimpleMetricKeyGenerator(context.system.settings.config)
-  val samplingRateFormat = new DecimalFormat()
-  samplingRateFormat.setMaximumFractionDigits(128) // Absurdly high, let the other end loss precision if it needs to.
+  val symbols = DecimalFormatSymbols.getInstance(Locale.US)
+  symbols.setDecimalSeparator('.') // Just in case there is some weird locale config we are not aware of.
+
+  // Absurdly high number of decimal digits, let the other end lose precision if it needs to.
+  val samplingRateFormat = new DecimalFormat("#.################################################################", symbols)
 
   udpExtension ! Udp.SimpleSender
 
@@ -45,14 +48,14 @@ class StatsDMetricsSender(remote: InetSocketAddress, maxPacketSize: Int) extends
   }
 
   def writeMetricsToRemote(tick: TickMetricSnapshot, udpSender: ActorRef): Unit = {
-    val dataBuilder = new MetricDataPacketBuilder(maxPacketSize, udpSender, remote)
+    val dataBuilder = new MetricDataPacketBuilder(maxPacketSizeInBytes, udpSender, remote)
 
     for (
       (groupIdentity, groupSnapshot) ← tick.metrics;
       (metricIdentity, metricSnapshot) ← groupSnapshot.metrics
     ) {
 
-      val key = ByteString(metricKeyGenerator.generateKey(groupIdentity, metricIdentity))
+      val key = metricKeyGenerator.generateKey(groupIdentity, metricIdentity)
 
       for (measurement ← metricSnapshot.measurements) {
         val measurementData = encodeMeasurement(measurement, metricSnapshot.instrumentType)
@@ -63,61 +66,63 @@ class StatsDMetricsSender(remote: InetSocketAddress, maxPacketSize: Int) extends
     dataBuilder.flush()
   }
 
-  def encodeMeasurement(measurement: Measurement, instrumentType: InstrumentType): ByteString = {
-    def statsDMetricFormat(value: String, metricType: String, samplingRate: Double = 1D): ByteString =
-      ByteString(value + "|" + metricType + (if (samplingRate != 1D) "|@" + samplingRateFormat.format(samplingRate) else ""))
+  def encodeMeasurement(measurement: Measurement, instrumentType: InstrumentType): String = {
+    def statsDMetricFormat(value: String, metricType: String, samplingRate: Double = 1D): String =
+      value + "|" + metricType + (if (samplingRate != 1D) "|@" + samplingRateFormat.format(samplingRate) else "")
 
     instrumentType match {
       case Histogram ⇒ statsDMetricFormat(measurement.value.toString, "ms", (1D / measurement.count))
       case Gauge     ⇒ statsDMetricFormat(measurement.value.toString, "g")
-      case Counter   ⇒ ByteString.empty // TODO: Need to decide how to report counters, when we have them!
+      case Counter   ⇒ statsDMetricFormat(measurement.count.toString, "c")
     }
   }
 }
 
 object StatsDMetricsSender {
-  def props(remote: InetSocketAddress, maxPacketSize: Int): Props = Props(new StatsDMetricsSender(remote, maxPacketSize))
+  def props(remote: InetSocketAddress, maxPacketSize: Long): Props = Props(new StatsDMetricsSender(remote, maxPacketSize))
 }
 
 trait UdpExtensionProvider {
   def udpExtension(implicit system: ActorSystem): ActorRef = IO(Udp)
 }
 
-class MetricDataPacketBuilder(maxPacketSize: Int, udpSender: ActorRef, remote: InetSocketAddress) {
-  val metricSeparator = ByteString("\n")
-  val measurementSeparator = ByteString(":")
+class MetricDataPacketBuilder(maxPacketSizeInBytes: Long, udpSender: ActorRef, remote: InetSocketAddress) {
+  val metricSeparator = "\n"
+  val measurementSeparator = ":"
 
-  var lastKey = ByteString.empty
-  var buffer = ByteString.empty
+  var lastKey = ""
+  var buffer = new StringBuilder()
 
-  def appendMeasurement(key: ByteString, measurementData: ByteString): Unit = {
+  def appendMeasurement(key: String, measurementData: String): Unit = {
     if (key == lastKey) {
-      val dataWithoutKey = measurementSeparator ++ measurementData
+      val dataWithoutKey = measurementSeparator + measurementData
       if (fitsOnBuffer(dataWithoutKey))
-        buffer = buffer ++ dataWithoutKey
+        buffer.append(dataWithoutKey)
       else {
-        flushToUDP(buffer)
-        buffer = key ++ dataWithoutKey
+        flushToUDP(buffer.toString())
+        buffer.clear()
+        buffer.append(key).append(dataWithoutKey)
       }
     } else {
       lastKey = key
-      val dataWithoutSeparator = key ++ measurementSeparator ++ measurementData
-      if (fitsOnBuffer(metricSeparator ++ dataWithoutSeparator)) {
-        val mSeparator = if (buffer.length > 0) metricSeparator else ByteString.empty
-        buffer = buffer ++ mSeparator ++ dataWithoutSeparator
+      val dataWithoutSeparator = key + measurementSeparator + measurementData
+      if (fitsOnBuffer(metricSeparator + dataWithoutSeparator)) {
+        val mSeparator = if (buffer.length > 0) metricSeparator else ""
+        buffer.append(mSeparator).append(dataWithoutSeparator)
       } else {
-        flushToUDP(buffer)
-        buffer = dataWithoutSeparator
+        flushToUDP(buffer.toString())
+        buffer.clear()
+        buffer.append(dataWithoutSeparator)
       }
     }
   }
 
-  def fitsOnBuffer(bs: ByteString): Boolean = (buffer.length + bs.length) <= maxPacketSize
+  def fitsOnBuffer(data: String): Boolean = (buffer.length + data.length) <= maxPacketSizeInBytes
 
-  private def flushToUDP(bytes: ByteString): Unit = udpSender ! Udp.Send(bytes, remote)
+  private def flushToUDP(data: String): Unit = udpSender ! Udp.Send(ByteString(data), remote)
 
   def flush(): Unit = {
-    flushToUDP(buffer)
-    buffer = ByteString.empty
+    flushToUDP(buffer.toString)
+    buffer.clear()
   }
 }
\ No newline at end of file
diff --git a/kamon-statsd/src/test/scala/kamon/statsd/StatsDMetricSenderSpec.scala b/kamon-statsd/src/test/scala/kamon/statsd/StatsDMetricSenderSpec.scala
index 6fdb48f1..9dfd05f7 100644
--- a/kamon-statsd/src/test/scala/kamon/statsd/StatsDMetricSenderSpec.scala
+++ b/kamon-statsd/src/test/scala/kamon/statsd/StatsDMetricSenderSpec.scala
@@ -1,6 +1,6 @@
 /*
  * =========================================================================================
- * Copyright © 2013 the kamon project <http://kamon.io/>
+ * Copyright © 2013-2014 the kamon project <http://kamon.io/>
  *
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
  * except in compliance with the License. You may obtain a copy of the License at
@@ -16,7 +16,7 @@
 
 package kamon.statsd
 
-import akka.testkit.{ TestKit, TestProbe }
+import akka.testkit.{ TestKitBase, TestProbe }
 import akka.actor.{ ActorRef, Props, ActorSystem }
 import org.scalatest.{ Matchers, WordSpecLike }
 import kamon.metrics._
@@ -24,10 +24,12 @@ import akka.io.Udp
 import org.HdrHistogram.HdrRecorder
 import kamon.metrics.Subscriptions.TickMetricSnapshot
 import java.lang.management.ManagementFactory
-import kamon.Kamon
 import java.net.InetSocketAddress
+import com.typesafe.config.ConfigFactory
 
-class StatsDMetricSenderSpec extends TestKit(ActorSystem("statsd-metric-sender-spec")) with WordSpecLike with Matchers {
+class StatsDMetricSenderSpec extends TestKitBase with WordSpecLike with Matchers {
+  implicit lazy val system = ActorSystem("statsd-metric-sender-spec",
+    ConfigFactory.parseString("kamon.statsd.max-packet-size = 256 bytes"))
 
   "the StatsDMetricSender" should {
     "flush the metrics data after processing the tick, even if the max-packet-size is not reached" in new UdpListenerFixture {
@@ -72,7 +74,7 @@ class StatsDMetricSenderSpec extends TestKit(ActorSystem("statsd-metric-sender-s
     "flush the packet when the max-packet-size is reached" in new UdpListenerFixture {
       val testMetricName = "test-metric"
       val testMetricKey = buildMetricKey(testMetricName)
-      val testRecorder = HdrRecorder(1000L, 3, Scale.Unit)
+      val testRecorder = HdrRecorder(testMaxPacketSize, 3, Scale.Unit)
 
       var bytes = testMetricKey.length
       var level = 0
@@ -94,6 +96,7 @@ class StatsDMetricSenderSpec extends TestKit(ActorSystem("statsd-metric-sender-s
       val firstTestMetricKey = buildMetricKey(firstTestMetricName)
       val secondTestMetricName = "second-test-metric"
       val secondTestMetricKey = buildMetricKey(secondTestMetricName)
+
       val firstTestRecorder = HdrRecorder(1000L, 2, Scale.Unit)
       val secondTestRecorder = HdrRecorder(1000L, 2, Scale.Unit)
 
@@ -115,7 +118,7 @@ class StatsDMetricSenderSpec extends TestKit(ActorSystem("statsd-metric-sender-s
 
   trait UdpListenerFixture {
     val localhostName = ManagementFactory.getRuntimeMXBean.getName.split('@')(1)
-    val testMaxPacketSize = 256
+    val testMaxPacketSize = system.settings.config.getBytes("kamon.statsd.max-packet-size")
 
     def buildMetricKey(metricName: String): String = s"kamon.$localhostName.test-metric-category.test-group.$metricName"