Struct zarrs::array::codec::array_to_bytes::codec_chain::CodecChain

pub struct CodecChain { /* private fields */ }

A codec chain is a sequence of array to array, a bytes to bytes, and a sequence of array to bytes codecs.

A codec chain partial decoder may insert a cache: ArrayPartialDecoderCache or BytesPartialDecoderCache. For example, the output of the blosc/gzip codecs should be cached since they read and decode an entire chunk. If decoding (i.e. going backwards through a codec chain), then a cache may be inserted

• following the last codec with partial_decoder_decodes_all true, or
• preceding the first codec with partial_decoder_should_cache_input, whichever is further.

Implementations

impl CodecChain

pub fn new( array_to_array: Vec<Box<dyn ArrayToArrayCodecTraits>>, array_to_bytes: Box<dyn ArrayToBytesCodecTraits>, bytes_to_bytes: Vec<Box<dyn BytesToBytesCodecTraits>> ) -> Self

Create a new codec chain.

pub fn from_metadata(metadatas: &[Metadata]) -> Result<Self, PluginCreateError>

Create a new codec chain from a list of metadata.

Errors

Returns a PluginCreateError if:

• a codec could not be created,
• no array to bytes codec is supplied, or
• more than one array to bytes codec is supplied.

pub fn create_metadatas_opt( &self, options: &ArrayMetadataOptions ) -> Vec<Metadata>

Create codec chain metadata.

pub fn create_metadatas(&self) -> Vec<Metadata>

Create codec chain metadata with default options.

pub fn array_to_array_codecs(&self) -> &[Box<dyn ArrayToArrayCodecTraits>]

Get the array to array codecs

pub fn array_to_bytes_codec(&self) -> &Box<dyn ArrayToBytesCodecTraits>

Get the array to bytes codec

pub fn bytes_to_bytes_codecs(&self) -> &[Box<dyn BytesToBytesCodecTraits>]

Get the bytes to bytes codecs

Trait Implementations

impl ArrayCodecTraits for CodecChain

fn recommended_concurrency( &self, decoded_representation: &ChunkRepresentation ) -> Result<RecommendedConcurrency, CodecError>

Return the recommended concurrency for the requested decoded representation.

fn encode( &self, decoded_value: Vec<u8>, decoded_representation: &ChunkRepresentation, options: &CodecOptions ) -> Result<Vec<u8>, CodecError>

Encode a chunk.

fn decode( &self, encoded_value: Vec<u8>, decoded_representation: &ChunkRepresentation, options: &CodecOptions ) -> Result<Vec<u8>, CodecError>

Decode a chunk.

fn decode_into_array_view( &self, encoded_value: &[u8], decoded_representation: &ChunkRepresentation, array_view: &ArrayView<'_>, options: &CodecOptions ) -> Result<(), CodecError>

Decode into the subset of an array.

fn partial_decode_granularity( &self, decoded_representation: &ChunkRepresentation ) -> ChunkShape

Return the partial decode granularity.

impl ArrayToBytesCodecTraits for CodecChain

fn partial_decoder<'a>( &'a self, input_handle: Box<dyn BytesPartialDecoderTraits + 'a>, decoded_representation: &ChunkRepresentation, options: &CodecOptions ) -> Result<Box<dyn ArrayPartialDecoderTraits + 'a>, CodecError>

Initialise a partial decoder.

fn async_partial_decoder<'a, 'life0, 'life1, 'async_trait>( &'a self, input_handle: Box<dyn AsyncBytesPartialDecoderTraits + 'a>, decoded_representation: &'life0 ChunkRepresentation, options: &'life1 CodecOptions ) -> Pin<Box<dyn Future<Output = Result<Box<dyn AsyncArrayPartialDecoderTraits + 'a>, CodecError>> + Send + 'async_trait>>

where Self: 'async_trait, 'a: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Available on crate feature async only.

Initialise an asynchronous partial decoder.

fn compute_encoded_size( &self, decoded_representation: &ChunkRepresentation ) -> Result<BytesRepresentation, CodecError>

Returns the size of the encoded representation given a size of the decoded representation.

impl Clone for CodecChain

fn clone(&self) -> CodecChain

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl CodecTraits for CodecChain

fn create_metadata_opt( &self, _options: &ArrayMetadataOptions ) -> Option<Metadata>

Returns None since a codec chain does not have standard codec metadata.

Note that usage of the codec chain is explicit in Array and CodecChain::create_metadatas_opt() will call CodecTraits::create_metadata_opt() from for each codec.

fn partial_decoder_should_cache_input(&self) -> bool

Indicates if the input to a codecs partial decoder should be cached for optimal performance. If true, a cache may be inserted before it in a CodecChain partial decoder.

fn partial_decoder_decodes_all(&self) -> bool

Indicates if a partial decoder decodes all bytes from its input handle and its output should be cached for optimal performance. If true, a cache will be inserted at some point after it in a CodecChain partial decoder.

fn create_metadata(&self) -> Option<Metadata>

Create metadata with default options.

impl Debug for CodecChain

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.