Merge pull request apache#15 from ringtail/feature/spark-app-id

add spark id into sparkConf

resource-managers/kubernetes/core/src/main/scala/org/apache/spark/deploy/k8s/submit/KubernetesClientApplication.scala

@@ -210,7 +210,8 @@ private[spark] class KubernetesClientApplication extends SparkApplication {
     // to be added as a label to group resources belonging to the same application. Label values are
     // considerably restrictive, e.g. must be no longer than 63 characters in length. So we generate
     // a unique app ID (captured by spark.app.id) in the format below.
-    val kubernetesAppId = s"spark-${UUID.randomUUID().toString.replaceAll("-", "")}"
+    val kubernetesAppId = sparkConf.getOption("spark.app.id").
+      getOrElse(s"spark-${UUID.randomUUID().toString.replaceAll("-", "")}")
     val waitForAppCompletion = sparkConf.get(WAIT_FOR_APP_COMPLETION)
     val kubernetesResourceNamePrefix = KubernetesClientApplication.getResourceNamePrefix(appName)
     sparkConf.set(KUBERNETES_PYSPARK_PY_FILES, clientArguments.maybePyFiles.getOrElse(""))