[DOC] ext objects are also supported in queries

[smacrakis]

What do you want to do?

• [X ] Request a change to existing documentation

This page says that "plugin authors can add an ext object to the search response", but @reta says that queries can also have an ext section.

Also, the doc for the Rerank processor includes an ext in a search query.

I would be happy to edit this myself, but I don't know the rules around ext objects.

• [ ] Add new documentation
• [ ] Report a technical problem with the documentation
• [ ] Other

Tell us about your request. Provide a summary of the request and all versions that are affected.

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.

[hdhalter]

@gaobinlong , @heemin32 - Is this something you can help with?

[gaobinlong]

By diving deep into the ext object, I found it's defined in OpenSearch-core, that makes the search request could be extended by the plugins, plugins can subclass SeachExtBuilder to add their own ext section. Now we have RerankSearchExitBuilder implemented in neural-search plugin, and the type of ext is just a map, so I think we can give an example of the rerank ext object in the documentation of the search api.

[hdhalter]

By diving deep into the ext object, I found it's defined in OpenSearch-core, that makes the search request could be extended by the plugins, plugins can subclass SeachExtBuilder to add their own ext section. Now we have RerankSearchExitBuilder implemented in neural-search plugin, and the type of ext is just a map, so I think we can give an example of the rerank ext object in the documentation of the search api.

Who would be able to provide that example?