spring-data-elasticsearch breaks opensearch client with private field

[ptourneur]

Hello,

I have just updated my project to spring-boot 3.1 which brings spring-data 2023.0 which brings spring-data-elasticsearch:5.1.0.
In this PR fields of BaseQueryBuilder have been changed from protected to private and it breaks NativeSearchQueryBuilder from opensearch-project which extends it because it tries to access indicesOptions.

This is my first issue on an opensource project so maybe I'm wrong or it's opensearch-project which should adapt but for me this fields of BaseQueryBuilder should stay protected.

[sothawo]

When I look at https://github.com/opensearch-project/spring-data-opensearch#about-opensearch-versions-and-clients, the compatible version of Spring Data Elasticsearch is 5.0. So spring-data-opensearch would need to bed adapted for the new version and this change.

Every implementation of Query should extend BaseQuery and have a builder that extends BaseQueryBuilder. It then should have a constructor taking it own builder and pass that on to the super constructor where the fields from the BaseQueryBuilder are set on the BaseQuery properties. I do not see the need to make this builder properties protected. A derived builder has the with...() methods to set these and there are set on the query in the base constructor then.