Use DISPATCHER_QUEUE default value

Author: Pascal Gillet

resource-managers/mesos/src/main/scala/org/apache/spark/deploy/mesos/config.scala

@@ -113,8 +113,6 @@ package object config {
       .stringConf
       .createOptional
 
-  private[spark] val DEFAULT_QUEUE = "default"
-
   private[spark] val DISPATCHER_QUEUE =
     ConfigBuilder("spark.mesos.dispatcher.queue")
       .doc("Set the name of the dispatcher queue to which the application is submitted. " +
@@ -123,7 +121,7 @@ package object config {
         "the application is submitted to the \"default\" queue with 0.0 priority.")
       .version("3.1.0")
       .stringConf
-      .createWithDefaultString(DEFAULT_QUEUE)
+      .createWithDefaultString("default")
 
   private[spark] val DRIVER_LABELS =
     ConfigBuilder("spark.mesos.driver.labels")

resource-managers/mesos/src/main/scala/org/apache/spark/deploy/mesos/ui/MesosClusterPage.scala

@@ -69,7 +69,7 @@ private[mesos] class MesosClusterPage(parent: MesosClusterUI) extends WebUIPage(
     val id = submission.submissionId
     <tr>
       <td><a href={s"driver?id=$id"}>{id}</a></td>
-      <td>{submission.conf.get("spark.mesos.dispatcher.queue", config.DEFAULT_QUEUE)}</td>
+      <td>{submission.conf.get("spark.mesos.dispatcher.queue", config.DISPATCHER_QUEUE.defaultValueString)}</td>
       <td>{UIUtils.formatDate(submission.submissionDate)}</td>
       <td>{submission.command.mainClass}</td>
       <td>cpus: {submission.cores}, mem: {submission.mem}</td>
@@ -101,7 +101,7 @@ private[mesos] class MesosClusterPage(parent: MesosClusterUI) extends WebUIPage(
       <td><a href={s"driver?id=$id"}>{id}</a></td>
       {historyCol}
       <td>
-      {state.driverDescription.conf.get("spark.mesos.dispatcher.queue", config.DEFAULT_QUEUE)}
+      {state.driverDescription.conf.get("spark.mesos.dispatcher.queue", config.DISPATCHER_QUEUE.defaultValueString)}
       </td>
       <td>{UIUtils.formatDate(state.driverDescription.submissionDate)}</td>
       <td>{state.driverDescription.command.mainClass}</td>

resource-managers/mesos/src/main/scala/org/apache/spark/scheduler/cluster/mesos/MesosClusterScheduler.scala

@@ -390,8 +390,8 @@ private[spark] class MesosClusterScheduler(
   }
 
   private[mesos] def getDriverPriority(desc: MesosDriverDescription): Float = {
-    val queueName = desc.conf.get("spark.mesos.dispatcher.queue", config.DEFAULT_QUEUE)
-    if (queueName != config.DEFAULT_QUEUE) {
+    val queueName = desc.conf.get("spark.mesos.dispatcher.queue", config.DISPATCHER_QUEUE.defaultValueString)
+    if (queueName != config.DISPATCHER_QUEUE.defaultValueString) {
       queues.getOrElse(queueName, throw new NoSuchElementException(queueName))
     } else {
       0.0f