Struct FileReader 

pub struct FileReader<R> {
    pub index: Vec<IndexEntry>,
    pub kv: Vec<(String, KvValue)>,
    /* private fields */
}

Reads tensors from a seekable Hurray file.

Open with FileReader::open, then look up tensors by name with read_tensor or inspect metadata with tensor_names and kv.

Examples

use hurray_io::file::FileReader;

let file = tokio::fs::File::open("model.hrry").await?;
let mut reader = FileReader::open(file).await?;
println!("tensors: {:?}", reader.tensor_names().collect::<Vec<_>>());
let tensor = reader.read_tensor("embeddings").await?;
println!("buffer[0]: {} bytes", tensor.buffers[0].len());

Fields

index: Vec<IndexEntry>

Footer index: one entry per tensor, in file-write order (or sorted if SORTED_INDEX was set by the writer).

kv: Vec<(String, KvValue)>

File-level KV metadata (empty if the file has no KV section).

Implementations

impl<R: AsyncRead + AsyncSeek + Unpin> FileReader<R>

pub async fn open(inner: R) -> Result<Self>

Opens a Hurray file: reads the header, trailer, index, and KV section.

Errors

• Error::InvalidFileMagic — first 8 bytes are not HRRYFILE
• Error::UnsupportedContainerVersion — major version > 1
• Error::ReservedFileFlagBits — header file_flags has unknown bits set
• Error::InvalidTrailerMagic — trailer trailer_magic is not HRRY
• Error::IndexOverrunsTrailer — index section overlaps the trailer
• Error::IndexCrc32cMismatch — CRC-32C verification failed
• Error::DuplicateTensorName — index contains duplicate names
• Error::Io / Error::UnexpectedEof — I/O failures

pub fn with_max_composite_depth(self, max_composite_depth: usize) -> Self

Sets the maximum composite nesting depth accepted by read_composite. Default: DEFAULT_MAX_COMPOSITE_DEPTH.

pub fn tensor_names(&self) -> impl Iterator<Item = &str>

Returns the names of all tensors in the file, in index order.

pub fn kv(&self) -> &[(String, KvValue)]

Returns the file-level KV metadata.

pub async fn read_descriptor(&mut self, name: &str) -> Result<TensorDescriptor>

Decodes and returns the descriptor for name without reading buffer data.

Useful for inspecting dtype, shape, or layout before deciding whether to load the full tensor.

pub async fn read_tensor(&mut self, name: &str) -> Result<FileTensor>

Reads and returns a complete tensor (descriptor + all buffers).

pub async fn read_composite(&mut self, head_name: &str) -> Result<FileComposite>

Reads a composite tensor by its head name, reassembling the head with its members.

Members are recovered by file-offset adjacency: the head’s declared member_count tensors written immediately after it, recursively for nested composites. Recovery keys on the descriptor offset, not index position, so it is correct even when the file used the SORTED_INDEX option (which reorders the index array but not the file layout). The reassembled group is validated with [CompositeValidator].

Examples

use hurray_io::file::FileReader;

let file = tokio::fs::File::open("model.hrry").await?;
let mut reader = FileReader::open(file).await?;
let composite = reader.read_composite("weight").await?;
println!("{} member(s)", composite.members.len());

Errors

• Error::TensorNotFound — no tensor named head_name
• Error::NotAComposite — head_name exists but is not a composite head
• Error::TornComposite — fewer members follow the head than it declares
• Error::CompositeNestingTooDeep — nesting exceeded max_composite_depth
• Error::Core — composite validation failed

pub fn into_inner(self) -> R

Returns the underlying reader.

Trait Implementations

impl<R: Debug> Debug for FileReader<R>

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

Formats the value using the given formatter.