Should opensearch be a recognized backend type?

[yurishkuro]

In #3198 we added ability to auto-detect OpenSearch storage. Would it make sense to add opensearch as a valid backend choice for SPAN_STORAGE_TYPE?

cc @pavolloffay @jkowall @albertteoh @Ashmita152

[pavolloffay]

I don't see much value by adding opensearch as a valid storage option right now. It will make more sense once opensearch implementation diverges.

That said I don't have a strong opinion to add it right now and use the same implementation for both elasticsearch and opensearch.

[yurishkuro]

Yes, I meant using the same implementation for now. Having explicit opensearch option would server to goals:

• be a forward-compatible configuration option, since I am fairly certain we'll need to do it at some point in the future
• a bit of a positional statement saying that we prefer to support liberally-licensed storage, not the new ES license

[yurishkuro]

@pavolloffay #3255