chore(arrow-flight-sql): remove register_sql_info from FlightSqlService

[mnpw]

Which issue does this PR close?

N/A

Rationale for this change

FlightSqlService::register_sql_info appears to be stale artefact and it is effectively a no-op in the trait definition. It appears to be carried over from Go's BaseServer implementation.

Since FlightSqlService intends to represent Go's Server implementation instead it makes sense to remove this method from FlightSqlService.

Note: An alternative to removal of this method is change in its signature to FlightSqlService::register_sql_info(id: SqlInfo, result: SqlInfoValue). I can implement that instead as well but it deviates from what FlightSqlService trait should be doing.

What changes are included in this PR?

Remove register_sql_info from FlightSqlService

Are these changes tested?

Tested via -

cargo test -p arrow-flight --all-features

Are there any user-facing changes?

Yes. This removes a public trait method. Implementors that currently define register_sql_info as part of their FlightSqlService implementation must remove it.

[Rich-T-kid]

What are the downsides to keeping it? Since this is would be a breaking API change we'd need to depreciate it first.

• https://github.com/apache/arrow-rs#release-versioning-and-schedule
• #5368

[mnpw]

Thanks for reviewing!

What are the downsides to keeping it?

Keeping the method just adds noise to the trait definition and it's required to implement as there is no trait level default impl. So every implementor ends up adding a mock implementation for this method that likely doesn't do anything.

Since this is would be a breaking API change we'd need to depreciate it first.

I've added this method for deprecation along with a default impl so that it doesn't add noise to newer implementations until we can remove this

[Rich-T-kid]

makes sense to me, thanks @mnpw

[Rich-T-kid]

the next release is 60 I believe. I may be wrong.

[Rich-T-kid]

I think this should actually be v60.0.0 right?