YARN-9257. Distributed Shell client throws a NPE for a non-existent queue. Contributed by Charan Hebri.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-applications-distributedshell/src/main/java/org/apache/hadoop/yarn/applications/distributedshell/Client.java

@@ -651,6 +651,12 @@ public class Client {
     }
 
     QueueInfo queueInfo = yarnClient.getQueueInfo(this.amQueue);
+    if (queueInfo == null) {
+      throw new IllegalArgumentException(String
+          .format("Queue %s not present in scheduler configuration.",
+              this.amQueue));
+    }
+
     LOG.info("Queue info"
         + ", queueName=" + queueInfo.getQueueName()
         + ", queueCurrentCapacity=" + queueInfo.getCurrentCapacity()

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-applications-distributedshell/src/test/java/org/apache/hadoop/yarn/applications/distributedshell/TestDistributedShell.java

@@ -1630,4 +1630,20 @@ public class TestDistributedShell {
     client.init(args);
     client.run();
   }
+
+  @Test(expected = IllegalArgumentException.class)
+  public void testDistributedShellNonExistentQueue() throws Exception {
+    String[] args =  {
+        "--jar",
+        APPMASTER_JAR,
+        "--num_containers",
+        "1",
+        "--shell_command",
+        Shell.WINDOWS ? "dir" : "ls",
+        "--queue",
+        "non-existent-queue" };
+    Client client = new Client(new Configuration(yarnCluster.getConfig()));
+    client.init(args);
+    client.run();
+  }
 }