From 967e0e1b2ba21040e561f16d33ac9db788eb83e3 Mon Sep 17 00:00:00 2001
From: stack <stack@apache.org>
Date: Fri, 1 Nov 2019 16:56:35 -0700
Subject: [PATCH] HBASE-23244 NPEs running Canary

---
 .../java/org/apache/hadoop/hbase/tool/CanaryTool.java | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/tool/CanaryTool.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/tool/CanaryTool.java
index 6302df563c62..a967dab81750 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/tool/CanaryTool.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/tool/CanaryTool.java
@@ -492,7 +492,8 @@ public Void read() {
           sink.publishReadTiming(serverName, region, column, stopWatch.getTime());
         } catch (Exception e) {
           sink.publishReadFailure(serverName, region, column, e);
-          sink.updateReadFailures(region.getRegionNameAsString(), serverName.getHostname());
+          sink.updateReadFailures(region == null? "NULL": region.getRegionNameAsString(),
+              serverName == null? "NULL": serverName.getHostname());
         } finally {
           if (rs != null) {
             rs.close();
@@ -1579,6 +1580,10 @@ private static List<Future<Void>> sniff(final Admin admin, final Sink sink,
       try (RegionLocator regionLocator =
                admin.getConnection().getRegionLocator(tableDesc.getTableName())) {
         for (HRegionLocation location: regionLocator.getAllRegionLocations()) {
+          if (location == null) {
+            LOG.warn("Null location");
+            continue;
+          }
           ServerName rs = location.getServerName();
           RegionInfo region = location.getRegion();
           tasks.add(new RegionTask(admin.getConnection(), region, rs, (RegionStdOutSink)sink,
@@ -1795,6 +1800,10 @@ private Map<String, List<RegionInfo>> getAllRegionServerByName() {
           try (RegionLocator regionLocator =
                    this.admin.getConnection().getRegionLocator(tableDesc.getTableName())) {
             for (HRegionLocation location : regionLocator.getAllRegionLocations()) {
+              if (location == null) {
+                LOG.warn("Null location");
+                continue;
+              }
               ServerName rs = location.getServerName();
               String rsName = rs.getHostname();
               RegionInfo r = location.getRegion();