From bf2e4c9d6cbaccf8e1b01c774f92c2c99676716f Mon Sep 17 00:00:00 2001
From: d810146 <naden.franciscus@team.telstra.com>
Date: Fri, 7 Oct 2016 13:27:30 +1100
Subject: [PATCH] NIFI-2873: Nifi throws UnknownHostException with HA NameNode

---
 .../apache/nifi/processors/hive/PutHiveStreaming.java    | 3 +++
 .../java/org/apache/nifi/util/hive/HiveConfigurator.java | 9 +++++++++
 2 files changed, 12 insertions(+)

diff --git a/nifi-nar-bundles/nifi-hive-bundle/nifi-hive-processors/src/main/java/org/apache/nifi/processors/hive/PutHiveStreaming.java b/nifi-nar-bundles/nifi-hive-bundle/nifi-hive-processors/src/main/java/org/apache/nifi/processors/hive/PutHiveStreaming.java
index 84eda83c0aef..aea14e1a40bf 100644
--- a/nifi-nar-bundles/nifi-hive-bundle/nifi-hive-processors/src/main/java/org/apache/nifi/processors/hive/PutHiveStreaming.java
+++ b/nifi-nar-bundles/nifi-hive-bundle/nifi-hive-processors/src/main/java/org/apache/nifi/processors/hive/PutHiveStreaming.java
@@ -27,6 +27,7 @@
 import org.apache.avro.generic.GenericDatumWriter;
 import org.apache.avro.generic.GenericRecord;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hive.hcatalog.streaming.ConnectionError;
 import org.apache.hive.hcatalog.streaming.HiveEndPoint;
@@ -323,6 +324,8 @@ public void setup(final ProcessContext context) {
                 .withMaxOpenConnections(maxConnections)
                 .withHeartBeatInterval(heartbeatInterval);
 
+        hiveConfigurator.preload(hiveConfig);
+
         if (SecurityUtil.isSecurityEnabled(hiveConfig)) {
             final String principal = context.getProperty(kerberosProperties.getKerberosPrincipal()).getValue();
             final String keyTab = context.getProperty(kerberosProperties.getKerberosKeytab()).getValue();
diff --git a/nifi-nar-bundles/nifi-hive-bundle/nifi-hive-processors/src/main/java/org/apache/nifi/util/hive/HiveConfigurator.java b/nifi-nar-bundles/nifi-hive-bundle/nifi-hive-processors/src/main/java/org/apache/nifi/util/hive/HiveConfigurator.java
index 748847d5b5c2..8d9072058f8c 100644
--- a/nifi-nar-bundles/nifi-hive-bundle/nifi-hive-processors/src/main/java/org/apache/nifi/util/hive/HiveConfigurator.java
+++ b/nifi-nar-bundles/nifi-hive-bundle/nifi-hive-processors/src/main/java/org/apache/nifi/util/hive/HiveConfigurator.java
@@ -18,6 +18,7 @@
 
 import org.apache.commons.lang3.StringUtils;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hive.conf.HiveConf;
 import org.apache.hadoop.security.UserGroupInformation;
@@ -71,6 +72,14 @@ public Configuration getConfigurationFromFiles(final String configFiles) {
         return hiveConfig;
     }
 
+    public void preload(Configuration configuration) {
+        try {
+            FileSystem.get(configuration);
+        }catch(IOException ioe) {
+            // Suppress exception as future uses of this configuration will fail
+        }
+    }
+
     public UserGroupInformation authenticate(final Configuration hiveConfig, String principal, String keyTab, long ticketRenewalPeriod, ComponentLog log) throws AuthenticationFailedException {
 
         UserGroupInformation ugi;