RestHighLevelClient in spring boot 2.1.x doesn't allow a spring cloud task to finish successfully

[VernonG07]

Elasticsearch version (bin/elasticsearch --version):
Tested with 6.4.2 through 7.0.0

JVM version (java -version):

java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, mixed mode)

OS version (uname -a if on a Unix-like system):

Description of the problem including expected versus actual behavior:
Including elasticsearch-rest-high-level-client on the classpath for a spring-boot, spring cloud task service does not properly close and therefor doesn't die after the task is complete.

Removing Elasticsearch from the classpath allows the spring cloud task to function correctly and die after the task is finished.

Steps to reproduce:

1. Clone https://github.com/spring-cloud/spring-cloud-task/tree/master/spring-cloud-task-samples/timestamp
2. Run the application - The service dies after it prints the timestamp
3. Add

                <dependency>
			<groupId>org.elasticsearch.client</groupId>
			<artifactId>elasticsearch-rest-high-level-client</artifactId>
			<version>7.0.0</version>
		</dependency>

4. Re-run the application - The service now stays alive

Notes
With:
Spring Cloud Task - Finchley.SR3
Spring Boot - 2.0.x
Rest High Level Client - 6.4.2
The app functions as intended.
With:
Spring Cloud Task - Greenwich.SR1
Spring Boot -2.1.x
Rest High Level Client - 6.4.2
The app exhibits the problematic behavior

[dadoonet]

When using springboot with
elasticsearch, you need to be explicit with some transitive dependencies as SpringBoot declares a version 6.4...

Basically you can put this in your pom.xml:

<properties>
  <elasticsearch.version>7.0.0<elasticsearch.version>
</properties>

See documentation here: https://docs.spring.io/spring-boot/docs/current/reference/html/howto-build.html#howto-customize-dependency-versions

Could you next time ask on discuss.elastic.co instead?

[astefan]

@VernonG07 I don't think this has anything to do specifically with Elasticsearch. From what I remember, Spring (and Spring Boot) do have ways to define/configure "destroy" like behavior for each of its components (beans). And the HLRC makes no exception imo.
Have a look here for an example - Step 6.

[VernonG07]

@astefan I should have mentioned that I also have a @configuration with a RestHighLevelClient @bean. I made sure to close the RestHighLevelClient as well as the LowLevelClient on task completion. Still doesn't behave as expected. It also confusing that the exact same configuration for Spring Boot 2.0.x and Spring Cloud Finchley work just fine.
@dadoonet I have followed your advice and created something on discuss.elastic.co

UPDATE: looks like it was an Elasticsearch Autoconfig issue that is now included in spring boot 2.1.x