HBASE-29223 Migrate Master Status Jamon page back to JSP

[PDavid]

ℹ️ Sorry, this PR is quite large. Maybe it is better to check the changes commit-by-commit.

This is the first step of the Jamon to JSP migration is the Master Status page.

Moved the Jamon code back to JSP. Changed the Jamon syntax back to JSP.
To transfer data between JSP pages I used request attributes.
Tried to preserve the code as much as possible but did some changes:

Sub-templates were usually extracted to separate JSP file (and included with <jsp:include), in some case it was extracted as Java method.

Extracted some sections from master page to separate JSP pages:

• Software Attributes
• Warnings

Extracted the long JavaScript from the master page which executes on page load to separate JS file.

Extracted some frequently used static methods to a new util class: MasterStatusUtil. Also added unit tests for the static methods in MasterStatusUtil.

Changed the Master Status page back to /master.jsp again. Now made sure that /master-status redirects to /master.jsp.

What do you think about this?

I'll create a new Jira for the rest of the Jamon files.

[PDavid]

Maybe we could just have these constants in MasterStatusUtil and then we don't need a separate class for this. What do you think?

[stoty]

No preference from me.

[PDavid]

I tested this locally in standalone mode after building with maven (mvn clean install -DskipTests && bin/start-hbase.sh). I created some tables, adding data with the ltt tool (bin/hbase ltt -num_keys 10000 -write 100:100 -num_tables 10 -multiput)

I will still have to test these special cases as these have special UI parts:

• Dead region servers
• Replication - peers
• Backup master
• RS groups

I will also test with Pseudo-Distributed mode.

[Apache9]

Let me see if the copilot can give some feedbacks since this is a very big change...

[Copilot]

Copilot reviewed 39 out of 45 changed files in this pull request and generated 3 comments.

Files not reviewed (6)

• hbase-server/src/main/jamon/org/apache/hadoop/hbase/tmpl/master/AssignmentManagerStatusTmpl.jamon: Language not supported
• hbase-server/src/main/jamon/org/apache/hadoop/hbase/tmpl/master/BackupMasterStatusTmpl.jamon: Language not supported
• hbase-server/src/main/jamon/org/apache/hadoop/hbase/tmpl/master/RSGroupListTmpl.jamon: Language not supported
• hbase-server/src/main/jamon/org/apache/hadoop/hbase/tmpl/master/RegionVisualizerTmpl.jamon: Language not supported
• hbase-server/src/main/jamon/org/apache/hadoop/hbase/tmpl/regionserver/RSStatusTmpl.jamon: Language not supported
• hbase-server/src/main/resources/hbase-webapps/master/index.html: Language not supported

[Copilot]

This line assumes that server2GroupMap.get(serverName.getAddress()) is non-null. Add a null check before calling getName() to avoid a possible NullPointerException.

Suggested change

	rsGroupName = server2GroupMap.get(serverName.getAddress()).getName();
	}
	RSGroupInfo groupInfo = server2GroupMap.get(serverName.getAddress());
	if (groupInfo != null) {
	rsGroupName = groupInfo.getName();
	} else {
	rsGroupName = "default";
	}
	}

[PDavid]

To be honest I'm not sure if this is a good suggestion.
What do you all think?

[PDavid]

For now I only added these assertions on the HTML content of the Master Status page. But we can add more sophisticated asserts in the future.