[ZEPPELIN-6237] Add serviceLocator shutdown when server is close

[proceane]

What is this PR for?

In the zeppelin-server/rest module, it was observed that when running multiple tests together, configuration values of notebooks used in previous tests remain.
To address this, code has been added to shutdown serviceLocator when the test finishes and the server is stopped.

What type of PR is it?

Bug Fix

Todos

• Add serviceLocatior shutdown

What is the Jira issue?

https://issues.apache.org/jira/browse/ZEPPELIN-6237

How should this be tested?

• In the zeppelin-server/rest module, run test.

Screenshots (if appropriate)

Questions:

• Does the license files need to update? No
• Is there breaking changes for older versions? No
• Does this needs documentation? No

[Reamer]

This pull request is a workaround for me, because the ServiceLocator should actually be executed when Zeppelin is shut down.

zeppelin/zeppelin-server/src/main/java/org/apache/zeppelin/server/ZeppelinServer.java

Lines 357 to 377 in d774044

	public void shutdown(int exitCode) {
	if (!duringShutdown.getAndSet(true)) {
	LOGGER.info("Shutting down Zeppelin Server ... - ExitCode {}", exitCode);
	try {
	if (jettyWebServer != null) {
	jettyWebServer.stop();
	}
	if (sharedServiceLocator != null) {
	if (!zConf.isRecoveryEnabled()) {
	sharedServiceLocator.getService(InterpreterSettingManager.class).close();
	}
	sharedServiceLocator.getService(Notebook.class).close();
	}
	} catch (Exception e) {
	LOGGER.error("Error while stopping servlet container", e);
	}
	LOGGER.info("Bye");
	if (exitCode != 0) {
	System.exit(exitCode);
	}
	}

Somewhere here should be sharedServiceLocator.shutdown();.

Unfortunately, my efforts failed because of the recovery tests.
Would you like to try a real shutdown here?

In my opinion, the close() method of the “services” must take the recovery mechanism into account and not at the top of the Zeppelin server.

[Reamer]

Yes, this is the simple variant, but it actually belongs outside the ‘if’ statement.