mkarbo commented on code in PR #7535: URL: https://github.com/apache/arrow-rs/pull/7535#discussion_r2103398459
########## parquet-variant/src/decoder.rs: ########## @@ -0,0 +1,199 @@ +// NOTE: Largely based on the implementation of @PinkCrow007 in https://github.com/apache/arrow-rs/pull/7452 +// And the feedback there. +use crate::variant::VariantType; +use arrow_schema::ArrowError; +use std::{array::TryFromSliceError, str}; + +#[derive(Debug, Clone, Copy)] +pub enum VariantBasicType { + Primitive = 0, + ShortString = 1, + Object = 2, + Array = 3, +} + +#[derive(Debug, Clone, Copy)] +pub enum VariantPrimitiveType { + Null = 0, + BooleanTrue = 1, + BooleanFalse = 2, + Int8 = 3, + // TODO: Add 'legs' for the rest of primitives, once API is agreed upon + String = 16, +} + +/// Extracts the basic type from a header byte +pub(crate) fn get_basic_type(header: u8) -> Result<VariantBasicType, ArrowError> { + // See https://github.com/apache/parquet-format/blob/master/VariantEncoding.md#value-encoding + let basic_type = header & 0x03; // Basic type is encoded in the first 2 bits + let basic_type = match basic_type { + 0 => VariantBasicType::Primitive, + 1 => VariantBasicType::ShortString, + 2 => VariantBasicType::Object, + 3 => VariantBasicType::Array, + _ => { + return Err(ArrowError::InvalidArgumentError(format!( + "unknown basic type: {}", + basic_type + ))) + } Review Comment: Done! -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@arrow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
