feat(flight): add sql-info helpers

[roeap]

Which issue does this PR close?

Closes #4256

Rationale for this change

see #4256

What changes are included in this PR?

• ported and slightly adopted sql info related structs and enums from iOx
• show how they can be used in example server
• tests
• docs

@alamb, here a first draft of how it might look like with SqlInfoList et al. an feedback if this is going in the right direction is highly appreciated.

Are there any user-facing changes?

Users can now use SqlInfoList to easily implement flight sql methods related to communicating server capabilities.

[roeap]

Here I have the most doubts if this is going a bit too far? On one hand the logic should mostly be static if one implements "vanilla" flight-sql, but if still wanted to keep the option to adjust the ticket and descriptor to ones liking. with that flexibility, there is an argument though to just include it in the example server, and stick to just exposing the schema method.

[alamb]

I wonder if the reason you are including this function because it is somewhat challenging to create a FlightInfo (especially the magic dance to encode the schema).

I wonder if we could get a similar effect by adding some builder style structures to FlightInfo, so constructing one could look like:

let flight_info = FlightInfoBuilder::new()
  .with_schema(schema),
  .with_ticket(ticket)
  .build()

That might help other people work with these structures and we could avoid this specific API.

What do you think?

[alamb]

Filed #4281 to track the idea

[roeap]

great idea - should I remove this here then, or should we just go-ahead with the PR you build on top of this in include this?

[alamb]

For this PR, I recommend we move flight_info out of SqlInfoBuilder and into the callsite(s) where it is needed.

I hope to bash out the FlightInfoBuilder later today or over the weekend and can update the callsites then

Thank you for your help with this

[alamb]

Thanks @roeap ! I plan to give this a look and review tomorrow morning!

[alamb]

Thanks @roeap -- this looks very nice (though of course I am biased) -- sorry for the delay in review.

[alamb]

I wonder if the reason you are including this function because it is somewhat challenging to create a FlightInfo (especially the magic dance to encode the schema).

I wonder if we could get a similar effect by adding some builder style structures to FlightInfo, so constructing one could look like:

let flight_info = FlightInfoBuilder::new()
  .with_schema(schema),
  .with_ticket(ticket)
  .build()

That might help other people work with these structures and we could avoid this specific API.

What do you think?

[alamb]

Thanks @roeap -- this looks awesome!