From a8fb7cb0be0588d4c31a1fc24c3473ef39562be5 Mon Sep 17 00:00:00 2001
From: Terence Yim <terence@cask.co>
Date: Tue, 23 Feb 2016 16:27:48 -0800
Subject: [PATCH] [SPARK-13441] [YARN] Fix NPE in yarn Client.createConfArchive
 method

- Log a warning instead of throwing NPE if either
  $HADOOP_CONF_DIR or $YARN_CONF_DIR is not accessible.
---
 .../scala/org/apache/spark/deploy/yarn/Client.scala   | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala b/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala
index d4ca255953a4..530f1d753b13 100644
--- a/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala
+++ b/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala
@@ -537,9 +537,14 @@ private[spark] class Client(
       sys.env.get(envKey).foreach { path =>
         val dir = new File(path)
         if (dir.isDirectory()) {
-          dir.listFiles().foreach { file =>
-            if (file.isFile && !hadoopConfFiles.contains(file.getName())) {
-              hadoopConfFiles(file.getName()) = file
+          val files = dir.listFiles()
+          if (files == null) {
+            logWarning("Failed to list files under directory " + dir)
+          } else {
+            files.foreach { file =>
+              if (file.isFile && !hadoopConfFiles.contains(file.getName())) {
+                hadoopConfFiles(file.getName()) = file
+              }
             }
           }
         }