Blosc codec config allow deserialization with missing typesize/`shu…

…ffle`

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
  - Fixed various errors in storage docs
+ - Blosc codec config allow deserialization with missing `typesize`/`shuffle`
 
 ## [0.12.2] - 2024-02-26
 

src/array/codec/bytes_to_bytes/blosc.rs

@@ -100,11 +100,12 @@ impl<'de> serde::Deserialize<'de> for BloscCompressionLevel {
 }
 
 /// The `blosc` shuffle mode.
-#[derive(Serialize, Deserialize, Copy, Clone, Debug, Eq, PartialEq)]
+#[derive(Serialize, Deserialize, Copy, Clone, Debug, Eq, PartialEq, Default)]
 #[serde(rename_all = "lowercase")]
 #[repr(u32)]
 pub enum BloscShuffleMode {
     /// No shuffling.
+    #[default]
     NoShuffle = BLOSC_NOSHUFFLE,
     /// Byte-wise shuffling.
     Shuffle = BLOSC_SHUFFLE,

src/array/codec/bytes_to_bytes/blosc/blosc_codec.rs

@@ -32,7 +32,7 @@ pub struct BloscCodec {
 impl BloscCodec {
     /// Create a new `blosc` codec.
     ///
-    /// The block size is chosen automatically if `blocksize` is none.
+    /// The block size is chosen automatically if `blocksize` is none or zero.
     /// `typesize` must be a positive integer if shuffling is enabled.
     ///
     /// # Errors

src/array/codec/bytes_to_bytes/blosc/blosc_configuration.rs

@@ -21,13 +21,25 @@ pub struct BloscCodecConfigurationV1 {
     /// The compression level.
     pub clevel: BloscCompressionLevel,
     /// The shuffle mode.
+    ///
+    /// Defaults to noshuffle if unspecified.
+    #[serde(default)]
     pub shuffle: BloscShuffleMode,
     /// The type size in bytes.
+    ///
+    /// Required unless shuffle is "noshuffle", in which case the value is ignored.
+    // FIXME: Change to option on major release
+    #[serde(default, skip_serializing_if = "usize_is_zero")]
     pub typesize: usize,
-    /// The compression block size. Automatically determined if [`None`].
+    /// The compression block size. Automatically determined if [`None`] or 0.
+    // FIXME: Change to usize on major version change
     pub blocksize: Option<usize>,
 }
 
+fn usize_is_zero(v: &usize) -> bool {
+    v == &0
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -62,6 +74,47 @@ mod tests {
         .unwrap();
     }
 
+    #[test]
+    fn codec_blosc_invalid_no_typesize() {
+        serde_json::from_str::<BloscCodecConfiguration>(
+            r#"
+        {
+            "cname": "lz4",
+            "clevel": 4,
+            "shuffle": "bitshuffle",
+            "blocksize": 0
+        }"#,
+        )
+        .unwrap();
+    }
+
+    #[test]
+    fn codec_blosc_valid_no_shuffle() {
+        serde_json::from_str::<BloscCodecConfiguration>(
+            r#"
+        {
+            "cname": "lz4",
+            "clevel": 4,
+            "blocksize": 0
+        }"#,
+        )
+        .unwrap();
+    }
+
+    #[test]
+    fn codec_blosc_valid_no_typesize() {
+        serde_json::from_str::<BloscCodecConfiguration>(
+            r#"
+        {
+            "cname": "lz4",
+            "clevel": 4,
+            "shuffle": "shuffle",
+            "blocksize": 0
+        }"#,
+        )
+        .unwrap();
+    }
+
     #[test]
     fn codec_blosc_invalid_clevel() {
         let json = r#"