refactor: restrict ParquetOpener field visibility to pub(crate)

[xudong963]

This is a follow-up of the comment

[adriangb]

This sounds good to me. We’ve made breaking changes to this struct before by moving around fields that would have been non breaking if they weren’t public, and as far as I can tell it was somewhat accidental to make them pub instead of pub(crate) in the first place.

Could you do a quick GitHub search to see if anyone is using these fields? Could check Delta, Comet, etc.

Assuming we don’t find any usage in the wild, how do we inform users? I think we should at least say that any requests to make these fields public we are happy to honor, add public methods for, etc. Basically if you were using this sorry about the breakage happy to revert.

[Jefffrey]

This sounds good to me. We’ve made breaking changes to this struct before by moving around fields that would have been non breaking if they weren’t public, and as far as I can tell it was somewhat accidental to make them pub instead of pub(crate) in the first place.

Could you do a quick GitHub search to see if anyone is using these fields? Could check Delta, Comet, etc.

Assuming we don’t find any usage in the wild, how do we inform users? I think we should at least say that any requests to make these fields public we are happy to honor, add public methods for, etc. Basically if you were using this sorry about the breakage happy to revert.

Is ParquetOpener part of the public API? It's marked as pub(super) 🤔

[adriangb]

Ah you're right! Then this is a meaningless exercise: pub fields on a pub(super) struct are not actually part of the public API / changing them is not a breaking change for users.

Thank you for following up @xudong963, it seems I was wrong with my original comment and it was a waste of time. Sorry about that...

[xudong963]

Thank you for following up @xudong963, it seems I was wrong with my original comment and it was a waste of time. Sorry about that...

No worries, also learned something