replace auto settings for environment with actual values

1 files changed, 51 insertions, 0 deletions

diff --git a/kamon-core/src/main/scala/kamon/Environment.scala b/kamon-core/src/main/scala/kamon/Environment.scala
new file mode 100644
index 00000000..80833352
--- /dev/null
+++ b/kamon-core/src/main/scala/kamon/Environment.scala
@@ -0,0 +1,51 @@
+/* =========================================================================================
+ * Copyright © 2013-2017 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
+
+import java.net.InetAddress
+import java.util.concurrent.ThreadLocalRandom
+
+import com.typesafe.config.Config
+import kamon.util.HexCodec
+
+case class Environment(host: String, service: String, instance: String, incarnation: String)
+
+object Environment {
+  private val incarnation = HexCodec.toLowerHex(ThreadLocalRandom.current().nextLong())
+
+  def fromConfig(config: Config): Environment = {
+    val environmentConfig = config.getConfig("kamon.environment")
+
+    val service = environmentConfig.getString("service")
+
+    val host = readValueOrGenerate(
+      environmentConfig.getString("host"),
+      InetAddress.getLocalHost.getHostName
+    )
+
+    val instance = readValueOrGenerate(
+      environmentConfig.getString("instance"),
+      s"$service@$host"
+    )
+
+    Environment(host, service, instance, incarnation)
+  }
+
+  private def readValueOrGenerate(configuredValue: String, generator: => String): String =
+    if(configuredValue == "auto") generator else configuredValue
+
+
+}