1 files changed, 81 insertions, 0 deletions
diff --git a/kamon-play-2.4.x/src/main/scala/kamon/play/Play.scala b/kamon-play-2.4.x/src/main/scala/kamon/play/Play.scala
new file mode 100644
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+++ b/kamon-play-2.4.x/src/main/scala/kamon/play/Play.scala
@@ -0,0 +1,81 @@
+/*
+ * =========================================================================================
+ * 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
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ * =========================================================================================
+ */
+
+package kamon.play
+
+import akka.actor.{ ExtendedActorSystem, Extension, ExtensionId, ExtensionIdProvider }
+import akka.event.Logging
+import kamon.Kamon
+import kamon.http.HttpServerMetrics
+import play.api.libs.ws.WSRequest
+import play.api.mvc.RequestHeader
+
+object Play extends ExtensionId[PlayExtension] with ExtensionIdProvider {
+  override def lookup(): ExtensionId[_ <: Extension] = Play
+  override def createExtension(system: ExtendedActorSystem): PlayExtension = new PlayExtension(system)
+
+  val SegmentLibraryName = "WS-client"
+}
+
+class PlayExtension(private val system: ExtendedActorSystem) extends Kamon.Extension {
+  val log = Logging(system, classOf[PlayExtension])
+  log.info(s"Starting the Kamon(Play) extension")
+
+  private val config = system.settings.config.getConfig("kamon.play")
+  val httpServerMetrics = Kamon.metrics.entity(HttpServerMetrics, "play-server")
+
+  val includeTraceToken: Boolean = config.getBoolean("automatic-trace-token-propagation")
+  val traceTokenHeaderName: String = config.getString("trace-token-header-name")
+
+  private val nameGeneratorFQN = config.getString("name-generator")
+  private val nameGenerator: NameGenerator = system.dynamicAccess.createInstanceFor[NameGenerator](nameGeneratorFQN, Nil).get
+
+  def generateTraceName(requestHeader: RequestHeader): String = nameGenerator.generateTraceName(requestHeader)
+  def generateHttpClientSegmentName(request: WSRequest): String = nameGenerator.generateHttpClientSegmentName(request)
+}
+
+trait NameGenerator {
+  def generateTraceName(requestHeader: RequestHeader): String
+  def generateHttpClientSegmentName(request: WSRequest): String
+}
+
+class DefaultNameGenerator extends NameGenerator {
+  import scala.collection.concurrent.TrieMap
+  import play.api.routing.Router
+  import java.util.Locale
+  import kamon.util.TriemapAtomicGetOrElseUpdate.Syntax
+
+  private val cache = TrieMap.empty[String, String]
+  private val normalizePattern = """\$([^<]+)<[^>]+>""".r
+
+  def generateTraceName(requestHeader: RequestHeader): String = requestHeader.tags.get(Router.Tags.RouteVerb).map { verb ⇒
+    val path = requestHeader.tags(Router.Tags.RoutePattern)
+    cache.atomicGetOrElseUpdate(s"$verb$path", {
+      val traceName = {
+        // Convert paths of form GET /foo/bar/$paramname<regexp>/blah to foo.bar.paramname.blah.get
+        val p = normalizePattern.replaceAllIn(path, "$1").replace('/', '.').dropWhile(_ == '.')
+        val normalisedPath = {
+          if (p.lastOption.filter(_ != '.').isDefined) s"$p."
+          else p
+        }
+        s"$normalisedPath${verb.toLowerCase(Locale.ENGLISH)}"
+      }
+      traceName
+    })
+  } getOrElse s"${requestHeader.method}: ${requestHeader.uri}"
+
+  def generateHttpClientSegmentName(request: WSRequest): String = request.url
+}