add support for logicalType

[carlos-markavip]

It would already be pretty useful to preserve logicalType as well as extra attributes when parsing the schema and when writing it back in a container header.

[mtth]

Good idea. Will include this in a future release.

[carlos-markavip]

OK, thanks for the quick reply. I'm in a hurry so I'll go ahead and implement this for my needs.
If you've got some thoughts about how you'd like to see this written I'd love to read them. That would improve the odds of contributing some generally useful code.

[mtth]

I'd like to think some more about how best to implement logical types, no definite ideas yet. I'm happy to review your code if you submit a pull request.

For your use-case, I wonder if being able to set the schema written by the BlockEncoder would be sufficient? If so, it would be straightforward to add a new key (e.g. schema) to its constructor's options, defaulting to the type's canonical schema.

[carlos-markavip]

For my current use case that would probably be enough for now, yes

[mtth]

Great, let's start with that then.

And come to think of it, it would be even better to change the first argument of BlockEncoder (and related functions) to accept a schema rather than only a type. The behavior would be consistent with parse, backwards compatible, and save adding a new option (along with the necessary compatibility check that would have been required).

If you can wait until tomorrow morning, I'll get this change out then.

[carlos-markavip]

Tomorrow would be great, thanks. I've made the change you suggested locally already, and it will be trivial the change the calling code again.

[mtth]

Done in df20230 and released in 2.4.0.

[carlos-markavip]

works for me, thanks