HBASE-29805: NullPointerException in AbstractRpcClient.createAddr after a RegionServer restart

[teamconfx]

Fix for HBASE-29805

Issue

A NullPointerException occurred in AbstractRpcClient.createAddr() when attempting to split a region after a RegionServer restart. The root cause was that node.getRegionLocation() can return null when a region is OPEN but not yet assigned to a server, and this wasn't being checked in SplitTableRegionProcedure.checkSplittable().

The Fix

Modified SplitTableRegionProcedure.java at line 208-227 to add an explicit null check for regionLocation before it's used:

  if (node != null) {
    // Check if region is assigned to a server before proceeding
    ServerName regionLocation = node.getRegionLocation();
    if (regionLocation == null) {
      throw new DoNotRetryIOException("Region " + regionToSplit.getShortNameToLog()
        + " is not assigned to any server. Cannot check splittability.");
    }
    // ... rest of the code uses regionLocation variable instead of node.getRegionLocation()
  }

Changes Made

• Added null check for regionLocation that throws a meaningful DoNotRetryIOException
• Stored node.getRegionLocation() in a local variable regionLocation to avoid redundant method calls
• Updated subsequent code to use the local regionLocation variable

[Apache-HBase]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	0m 29s		Docker mode activated.
			_ Prechecks _
+1 💚	dupname	0m 0s		No case conflicting files found.
+0 🆗	codespell	0m 0s		codespell was not available.
+0 🆗	detsecrets	0m 0s		detect-secrets was not available.
+1 💚	@author	0m 0s		The patch does not contain any @author tags.
+1 💚	hbaseanti	0m 0s		Patch does not have any anti-patterns.
			_ master Compile Tests _
+1 💚	mvninstall	3m 31s		master passed
+1 💚	compile	3m 32s		master passed
+1 💚	checkstyle	1m 1s		master passed
+1 💚	spotbugs	1m 42s		master passed
+1 💚	spotless	0m 53s		branch has no errors when running spotless:check.
			_ Patch Compile Tests _
+1 💚	mvninstall	3m 8s		the patch passed
+1 💚	compile	3m 32s		the patch passed
+1 💚	javac	3m 32s		the patch passed
+1 💚	blanks	0m 0s		The patch has no blanks issues.
+1 💚	checkstyle	0m 59s		the patch passed
+1 💚	spotbugs	1m 44s		the patch passed
+1 💚	hadoopcheck	12m 11s		Patch does not cause any errors with Hadoop 3.3.6 3.4.1.
+1 💚	spotless	0m 46s		patch has no errors when running spotless:check.
			_ Other Tests _
+1 💚	asflicense	0m 11s		The patch does not generate ASF License warnings.
		41m 36s

Subsystem	Report/Notes
Docker	ClientAPI=1.43 ServerAPI=1.43 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-7668/1/artifact/yetus-general-check/output/Dockerfile
GITHUB PR	#7668
JIRA Issue	HBASE-29805
Optional Tests	dupname asflicense javac spotbugs checkstyle codespell detsecrets compile hadoopcheck hbaseanti spotless
uname	Linux 056739229e6b 5.4.0-1103-aws #111~18.04.1-Ubuntu SMP Tue May 23 20:04:10 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/hbase-personality.sh
git revision	master / 4104c04
Default Java	Eclipse Adoptium-17.0.11+9
Max. process+thread count	84 (vs. ulimit of 30000)
modules	C: hbase-server U: hbase-server
Console output	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-7668/1/console
versions	git=2.34.1 maven=3.9.8 spotbugs=4.7.3
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[Apache-HBase]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	0m 28s		Docker mode activated.
-0 ⚠️	yetus	0m 3s		Unprocessed flag(s): --brief-report-file --spotbugs-strict-precheck --author-ignore-list --blanks-eol-ignore-file --blanks-tabs-ignore-file --quick-hadoopcheck
			_ Prechecks _
			_ master Compile Tests _
+1 💚	mvninstall	3m 38s		master passed
+1 💚	compile	1m 4s		master passed
+1 💚	javadoc	0m 31s		master passed
+1 💚	shadedjars	6m 0s		branch has no errors when building our shaded downstream artifacts.
			_ Patch Compile Tests _
+1 💚	mvninstall	3m 11s		the patch passed
+1 💚	compile	1m 0s		the patch passed
+1 💚	javac	1m 0s		the patch passed
+1 💚	javadoc	0m 28s		the patch passed
+1 💚	shadedjars	5m 56s		patch has no errors when building our shaded downstream artifacts.
			_ Other Tests _
+1 💚	unit	234m 26s		hbase-server in the patch passed.
		262m 15s

Subsystem	Report/Notes
Docker	ClientAPI=1.43 ServerAPI=1.43 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-7668/1/artifact/yetus-jdk17-hadoop3-check/output/Dockerfile
GITHUB PR	#7668
JIRA Issue	HBASE-29805
Optional Tests	javac javadoc unit compile shadedjars
uname	Linux 6f1c3ab6febd 5.4.0-1103-aws #111~18.04.1-Ubuntu SMP Tue May 23 20:04:10 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/hbase-personality.sh
git revision	master / 4104c04
Default Java	Eclipse Adoptium-17.0.11+9
Test Results	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-7668/1/testReport/
Max. process+thread count	4591 (vs. ulimit of 30000)
modules	C: hbase-server U: hbase-server
Console output	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-7668/1/console
versions	git=2.34.1 maven=3.9.8
Powered by	Apache Yetus 0.15.0 https://yetus.apache.org

This message was automatically generated.

[Apache9]

Is it possible to add a UT to reproduce the problem? And have you seen this in real world?