From 200bb27557d16f06220c150998e45e7d3d3d302d Mon Sep 17 00:00:00 2001
From: Vinod Kumar Vavilapalli <vinodkv@apache.org>
Date: Thu, 10 Nov 2011 19:19:25 +0000
Subject: [PATCH] MAPREDUCE-3392. Fixed Cluster's getDelegationToken's API to
 return null when there isn't a supported token. Contributed by John George.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1200484 13f79535-47bb-0310-9956-ffa450edef68
---
 hadoop-mapreduce-project/CHANGES.txt          |  3 +++
 .../org/apache/hadoop/mapreduce/Cluster.java  |  5 +++++
 .../TestYarnClientProtocolProvider.java       | 20 +++++++++++++++++++
 3 files changed, 28 insertions(+)

diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index b6530f82801..63d034098e4 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -105,6 +105,9 @@ Release 0.23.1 - Unreleased
     which per-container connections to NodeManager were lingering long enough
     to hit the ulimits on number of processes. (vinodkv)
 
+    MAPREDUCE-3392. Fixed Cluster's getDelegationToken's API to return null
+    when there isn't a supported token. (John George via vinodkv)
+
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Cluster.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Cluster.java
index 460202167dd..4828ebacaa0 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Cluster.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Cluster.java
@@ -390,6 +390,11 @@ public long getTaskTrackerExpiryInterval() throws IOException,
       getDelegationToken(Text renewer) throws IOException, InterruptedException{
     Token<DelegationTokenIdentifier> result =
       client.getDelegationToken(renewer);
+
+    if (result == null) {
+      return result;
+    }
+
     InetSocketAddress addr = Master.getMasterAddress(conf);
     StringBuilder service = new StringBuilder();
     service.append(NetUtils.normalizeHostName(addr.getAddress().
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/mapreduce/TestYarnClientProtocolProvider.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/mapreduce/TestYarnClientProtocolProvider.java
index 2bc9030bf85..490b7a546e6 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/mapreduce/TestYarnClientProtocolProvider.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/mapreduce/TestYarnClientProtocolProvider.java
@@ -25,6 +25,7 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.mapred.YARNRunner;
 import org.apache.hadoop.mapreduce.protocol.ClientProtocol;
+import org.apache.hadoop.io.Text;
 import org.junit.Test;
 
 public class TestYarnClientProtocolProvider extends TestCase {
@@ -56,4 +57,23 @@ public void testClusterWithYarnClientProtocolProvider() throws Exception {
       }
     }
   }
+
+ 
+  @Test
+  public void testClusterGetDelegationToken() throws Exception {
+
+    Configuration conf = new Configuration(false);
+    Cluster cluster = null;
+    try {
+      conf = new Configuration();
+      conf.set(MRConfig.FRAMEWORK_NAME, MRConfig.YARN_FRAMEWORK_NAME);
+      cluster = new Cluster(conf);
+      cluster.getDelegationToken(new Text(" "));
+    } finally {
+      if (cluster != null) {
+        cluster.close();
+      }
+    }
+  }
+
 }