Upgrade to Elasticsearch 8 from 7.16

Question

We deploy standalone ES pods and I saw that the system requirements say that Java 17 or higher is to be used. The java applications (separate pods of course) depending on ES are still on java 8 and we have no intention of upgrading the java version anytime soon. I wanted to confirm with the community at large if they faced issues any issues calling ES from applications on java 8? We are using the standard ES java libraries

org.elasticsearch.client:elasticsearch-rest-client
org.elasticsearch.plugin:parent-join-client
org.elasticsearch:elasticsearch-core
org.elasticsearch:elasticsearch
org.elasticsearch.client:elasticsearch-rest-high-level-client

I know restHighLevelClient is deprecated but we depend on spring-data-elasticsearch to provide some of the integration support.

Answer 1

I don't have enough reputation to add comment. I have similar problem on the upgrade. Here is from readme https://github.com/spring-projects/spring-data-elasticsearch

In Elasticsearch 8, the RestHighLevelCLient has been removed. This means that a switch to this client version can only be done with the next major upgrade which will be Spring Data Elasticsearch 5, based on Spring Data 3, used by Spring Boot 3, based on Spring 6 and Java 17.

Below has dependencies and upgrade info.

https://www.elastic.co/guide/en/elasticsearch/reference/current/dependencies-versions.html

https://www.elastic.co/guide/en/elasticsearch/reference/current/setup-upgrade.html