HBASE-29093 Load userSnapshots.jsp only on master status page

[PDavid]

Before HBase UI always tried to load userSnapshots.jsp with an AJAX request on all UI pages - NOK.

This happened even on RegionServer UI or REST UI where this call always failed with HTTP 500.

From now on HBase UI only loads userSnapshots.jsp when the Snapshots tab (div with tab_userSnapshots ID) exists on the page.

Also did a minor improvement to tab.js: use const instead of var as var has so many problems:

With block-level scope, no hoisting, and the ability to declare constants, let and const make code more predictable, maintainable, and less error-prone. By using let and const instead of var, developers can avoid common pitfalls and write more declarative code.

Also fixed a whitespace.

[PDavid]

Tested this locally with starting HBase in standalone mode.

After the fix, the Snapshots data is still loaded on Master status UI page:

Other Master UI pages like Table Details does not try to load userSnapshots.jsp anymore:

Region Server UI does not try to load userSnapshots.jsp anymore:

[Apache-HBase]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	0m 31s		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.
+0 🆗	jshint	0m 0s		jshint was not available.
+1 💚	@author	0m 0s		The patch does not contain any @author tags.
			_ master Compile Tests _
+1 💚	mvninstall	3m 19s		master passed
+1 💚	spotless	0m 45s		branch has no errors when running spotless:check.
			_ Patch Compile Tests _
+1 💚	mvninstall	2m 58s		the patch passed
+1 💚	blanks	0m 0s		The patch has no blanks issues.
+1 💚	spotless	0m 42s		patch has no errors when running spotless:check.
			_ Other Tests _
+1 💚	asflicense	0m 10s		The patch does not generate ASF License warnings.
		9m 56s

Subsystem	Report/Notes
Docker	ClientAPI=1.43 ServerAPI=1.43 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-6627/1/artifact/yetus-general-check/output/Dockerfile
GITHUB PR	#6627
Optional Tests	dupname asflicense javac codespell detsecrets jshint spotless
uname	Linux 1ed40ba9b340 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 / 80274ca
Default Java	Eclipse Adoptium-17.0.11+9
Max. process+thread count	82 (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-6627/1/console
versions	git=2.34.1 maven=3.9.8
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[PDavid]

This bug also exists on all the active branches. Should we backport this fix?

[Apache-HBase]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	0m 39s		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 31s		master passed
+1 💚	javadoc	0m 30s		master passed
			_ Patch Compile Tests _
+1 💚	mvninstall	3m 31s		the patch passed
+1 💚	javadoc	0m 33s		the patch passed
			_ Other Tests _
+1 💚	unit	252m 19s		hbase-server in the patch passed.
		266m 28s

Subsystem	Report/Notes
Docker	ClientAPI=1.43 ServerAPI=1.43 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-6627/1/artifact/yetus-jdk17-hadoop3-check/output/Dockerfile
GITHUB PR	#6627
Optional Tests	javac javadoc unit
uname	Linux 13562198d968 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 / 80274ca
Default Java	Eclipse Adoptium-17.0.11+9
Test Results	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-6627/1/testReport/
Max. process+thread count	5508 (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-6627/1/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.