Refactor partial decoder API (#76)

CHANGELOG.md

@@ -14,6 +14,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 - **Breaking**: Change `Contiguous[Linearised]Indices` iterators to return indices only
+- **Breaking**: Remove lifetime constraints in partial decoder API by utilising `Arc`'d codecs
+- **Breaking**: `ShardingCodec::new` `CodecChain` parameters now must be in an `Arc`
 
 ### Fixed
 - Fixed an unnecessary copy in `Array::[async_]retrieve_chunk_if_exists_opt`

zarrs/src/array.rs

@@ -304,7 +304,7 @@ pub struct Array<TStorage: ?Sized> {
     /// Provides an element value to use for uninitialised portions of the Zarr array. It encodes the underlying data type.
     fill_value: FillValue,
     /// Specifies a list of codecs to be used for encoding and decoding chunks.
-    codecs: CodecChain,
+    codecs: Arc<CodecChain>,
     // /// Optional user defined attributes.
     // attributes: serde_json::Map<String, serde_json::Value>,
     /// An optional list of storage transformers.
@@ -352,8 +352,10 @@ impl<TStorage: ?Sized> Array<TStorage> {
         let fill_value = data_type
             .fill_value_from_metadata(&metadata_v3.fill_value)
             .map_err(ArrayCreateError::InvalidFillValueMetadata)?;
-        let codecs = CodecChain::from_metadata(&metadata_v3.codecs)
-            .map_err(ArrayCreateError::CodecsCreateError)?;
+        let codecs = Arc::new(
+            CodecChain::from_metadata(&metadata_v3.codecs)
+                .map_err(ArrayCreateError::CodecsCreateError)?,
+        );
         let storage_transformers =
             StorageTransformerChain::from_metadata(&metadata_v3.storage_transformers)
                 .map_err(ArrayCreateError::StorageTransformersCreateError)?;
@@ -432,7 +434,7 @@ impl<TStorage: ?Sized> Array<TStorage> {
 
     /// Get the codecs.
     #[must_use]
-    pub const fn codecs(&self) -> &CodecChain {
+    pub fn codecs(&self) -> &CodecChain {
         &self.codecs
     }
 

zarrs/src/array/array_async_readable.rs

@@ -273,10 +273,10 @@ impl<TStorage: ?Sized + AsyncReadableStorageTraits + 'static> Array<TStorage> {
 
     /// Async variant of [`partial_decoder`](Array::partial_decoder).
     #[allow(clippy::missing_errors_doc, clippy::missing_panics_doc)]
-    pub async fn async_partial_decoder<'a>(
-        &'a self,
+    pub async fn async_partial_decoder(
+        &self,
         chunk_indices: &[u64],
-    ) -> Result<Arc<dyn AsyncArrayPartialDecoderTraits + 'a>, ArrayError> {
+    ) -> Result<Arc<dyn AsyncArrayPartialDecoderTraits>, ArrayError> {
         self.async_partial_decoder_opt(chunk_indices, &CodecOptions::default())
             .await
     }
@@ -768,7 +768,8 @@ impl<TStorage: ?Sized + AsyncReadableStorageTraits + 'static> Array<TStorage> {
                 storage_transformer,
                 self.chunk_key(chunk_indices),
             ));
-            self.codecs()
+            self.codecs
+                .clone()
                 .async_partial_decoder(input_handle, &chunk_representation, options)
                 .await?
                 .partial_decode_opt(&[chunk_subset.clone()], options)
@@ -820,7 +821,8 @@ impl<TStorage: ?Sized + AsyncReadableStorageTraits + 'static> Array<TStorage> {
             ));
 
             Ok(self
-                .codecs()
+                .codecs
+                .clone()
                 .async_partial_decoder(input_handle, &chunk_representation, options)
                 .await?
                 .partial_decode_into(chunk_subset, output, output_shape, output_subset, options)
@@ -860,11 +862,11 @@ impl<TStorage: ?Sized + AsyncReadableStorageTraits + 'static> Array<TStorage> {
 
     /// Async variant of [`partial_decoder_opt`](Array::partial_decoder_opt).
     #[allow(clippy::missing_errors_doc)]
-    pub async fn async_partial_decoder_opt<'a>(
-        &'a self,
+    pub async fn async_partial_decoder_opt(
+        &self,
         chunk_indices: &[u64],
         options: &CodecOptions,
-    ) -> Result<Arc<dyn AsyncArrayPartialDecoderTraits + 'a>, ArrayError> {
+    ) -> Result<Arc<dyn AsyncArrayPartialDecoderTraits>, ArrayError> {
         let storage_handle = Arc::new(StorageHandle::new(self.storage.clone()));
         let storage_transformer = self
             .storage_transformers()
@@ -875,7 +877,8 @@ impl<TStorage: ?Sized + AsyncReadableStorageTraits + 'static> Array<TStorage> {
         ));
         let chunk_representation = self.chunk_array_representation(chunk_indices)?;
         Ok(self
-            .codecs()
+            .codecs
+            .clone()
             .async_partial_decoder(input_handle, &chunk_representation, options)
             .await?)
     }

zarrs/src/array/array_builder.rs

@@ -335,11 +335,11 @@ impl ArrayBuilder {
             chunk_grid: self.chunk_grid.clone(),
             chunk_key_encoding: self.chunk_key_encoding.clone(),
             fill_value: self.fill_value.clone(),
-            codecs: CodecChain::new(
+            codecs: Arc::new(CodecChain::new(
                 self.array_to_array_codecs.clone(),
                 self.array_to_bytes_codec.clone(),
                 self.bytes_to_bytes_codecs.clone(),
-            ),
+            )),
             storage_transformers: self.storage_transformers.clone(),
             // attributes: self.attributes.clone(),
             dimension_names: self.dimension_names.clone(),

zarrs/src/array/array_sync_readable.rs

@@ -407,10 +407,10 @@ impl<TStorage: ?Sized + ReadableStorageTraits + 'static> Array<TStorage> {
     ///
     /// # Errors
     /// Returns an [`ArrayError`] if initialisation of the partial decoder fails.
-    pub fn partial_decoder<'a>(
-        &'a self,
+    pub fn partial_decoder(
+        &self,
         chunk_indices: &[u64],
-    ) -> Result<Arc<dyn ArrayPartialDecoderTraits + 'a>, ArrayError> {
+    ) -> Result<Arc<dyn ArrayPartialDecoderTraits>, ArrayError> {
         self.partial_decoder_opt(chunk_indices, &CodecOptions::default())
     }
 
@@ -830,7 +830,8 @@ impl<TStorage: ?Sized + ReadableStorageTraits + 'static> Array<TStorage> {
                 self.chunk_key(chunk_indices),
             ));
 
-            self.codecs()
+            self.codecs
+                .clone()
                 .partial_decoder(input_handle, &chunk_representation, options)?
                 .partial_decode_opt(&[chunk_subset.clone()], options)?
                 .remove(0)
@@ -873,7 +874,8 @@ impl<TStorage: ?Sized + ReadableStorageTraits + 'static> Array<TStorage> {
             ));
 
             Ok(self
-                .codecs()
+                .codecs
+                .clone()
                 .partial_decoder(input_handle, &chunk_representation, options)?
                 .partial_decode_into(chunk_subset, output, output_shape, output_subset, options)?)
         }
@@ -909,11 +911,11 @@ impl<TStorage: ?Sized + ReadableStorageTraits + 'static> Array<TStorage> {
 
     /// Explicit options version of [`partial_decoder`](Array::partial_decoder).
     #[allow(clippy::missing_errors_doc)]
-    pub fn partial_decoder_opt<'a>(
-        &'a self,
+    pub fn partial_decoder_opt(
+        &self,
         chunk_indices: &[u64],
         options: &CodecOptions,
-    ) -> Result<Arc<dyn ArrayPartialDecoderTraits + 'a>, ArrayError> {
+    ) -> Result<Arc<dyn ArrayPartialDecoderTraits>, ArrayError> {
         let storage_handle = Arc::new(StorageHandle::new(self.storage.clone()));
         let storage_transformer = self
             .storage_transformers()
@@ -924,7 +926,8 @@ impl<TStorage: ?Sized + ReadableStorageTraits + 'static> Array<TStorage> {
         ));
         let chunk_representation = self.chunk_array_representation(chunk_indices)?;
         Ok(self
-            .codecs()
+            .codecs
+            .clone()
             .partial_decoder(input_handle, &chunk_representation, options)?)
     }
 }