jecsand838 commented on code in PR #8006:
URL: https://github.com/apache/arrow-rs/pull/8006#discussion_r2234121122
##########
arrow-avro/src/schema.rs:
##########
@@ -260,13 +274,304 @@ pub struct Fixed<'a> {
pub attributes: Attributes<'a>,
}
+/// Supported fingerprint algorithms for Avro schema identification.
+/// Currently only `Rabin` is supported, `SHA256` and `MD5` support will come
in a future update
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub enum FingerprintAlgorithm {
+ /// 64‑bit CRC‑64‑AVRO Rabin fingerprint.
+ Rabin,
+}
+
+/// A schema fingerprint in one of the supported formats.
+///
+/// This is used as the key inside `SchemaStore` `HashMap`. Each `SchemaStore`
+/// instance always stores only one variant, matching its configured
+/// `FingerprintAlgorithm`, but the enum makes the API uniform.
+/// Currently only `Rabin` is supported
+///
+/// <https://avro.apache.org/docs/1.11.1/specification/#schema-fingerprints>
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub enum Fingerprint {
+ /// A 64-bit Rabin fingerprint.
+ Rabin(u64),
+}
+
+/// Allow easy extraction of the algorithm used to create a fingerprint.
+impl From<&Fingerprint> for FingerprintAlgorithm {
+ #[inline]
+ fn from(fp: &Fingerprint) -> Self {
+ match fp {
+ Fingerprint::Rabin(_) => FingerprintAlgorithm::Rabin,
+ }
+ }
+}
+
+/// Generates a fingerprint for the given `Schema` using the specified
`FingerprintAlgorithm`.
+#[inline]
+pub(crate) fn generate_fingerprint(
+ schema: &Schema,
+ hash_type: FingerprintAlgorithm,
+) -> Fingerprint {
+ let canonical = generate_canonical_form(schema);
+ match hash_type {
+ FingerprintAlgorithm::Rabin =>
Fingerprint::Rabin(compute_fingerprint_rabin(&canonical)),
Review Comment:
Correct unfortunately. The fingerprints are supposed to be of a `Schema` in
[canonical
form](https://avro.apache.org/docs/1.11.1/specification/#parsing-canonical-form-for-schemas)
Luckily, there shouldn't be a scenario where we need to parse a schema and
fingerprint it while decoding.
--
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
