Struct BlobMeta 

pub struct BlobMeta {
    chunk_metas: Arc<[ChunkMeta]>,
}

Describes information to assemble a Blob.

Currently stores only a list of non-empty chunk digests and offsets, but might gain bao support and other fields in the future.

(See https://snix.dev/docs/components/castore/blobstore-chunking-verified-streaming)

Fields

chunk_metas: Arc<[ChunkMeta]>

Implementations

impl BlobMeta

pub fn bytes_stream( &self, start_offset: u64, limit_size: Option<u64>, fetch_concurrency: usize, chunk_store: impl ChunkStore + Clone + 'static, ) -> impl Stream<Item = Result<Cursor<Chunk>>> + 'static

Returns a stream of bytes of actual blob bytes.

Both a start_offset and a size limit to read can be specified.

start_offset must be inside the range of the blob. If limit_size is set, the last element in the stream will contain a chunk with truncated data. If limit_size would point past the end of the blob, it’s clamped to the end.

Chunks not part of that range are skipped entirely. The returned Cursor into the first chunk is advanced to the desired start_offset.

Queries the passed ChunkStore, with configurable concurrency.

impl BlobMeta

pub fn blob_len(&self) -> u64

Returns the length of the blob.

pub fn from_digests_and_sizes<T: IntoIterator<Item = (B3Digest, u64)>>( iter: T, ) -> Self

Constructs from an iterator of digests and chunk sizes.

NOTE: The empty chunk is skipped silently, as there’s no point fetching it.

fn chunk_idx_from(&self, offset: u64) -> (usize, u64)

For a given offset into the blob, returns the index of the first chunk holding the requested bytes, as well as the number of bytes to skip inside the first chunk.

fn chunk_idx_until(&self, size: u64) -> (usize, u64)

For a given length into the blob, returns the index of the last chunk holding the requested bytes, and how many bytes of that chunk are still in range (chunk[..size])

Trait Implementations

impl Clone for BlobMeta

fn clone(&self) -> BlobMeta

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for BlobMeta

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

Formats the value using the given formatter.

impl From<BlobMeta> for BlobMeta

fn from(value: BlobMeta) -> Self

Converts to this type from the input type.

impl PartialEq for BlobMeta

fn eq(&self, other: &BlobMeta) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl TryFrom<BlobMeta> for BlobMeta

Constructs by parsing a proto::BlobMeta message.

This will reject a proto::BlobMeta message without any chunks. This is to prevent accidentially passing a StatBlobResponse message which historically omitted chunks in the single-chunk case.

It will also reject chunks with a size of zero

To explicitly create a BlobMeta for the empty blob, use BlobMeta::from_digests_and_sizes with an empty iterator instead.

type Error = DecodeError

The type returned in the event of a conversion error.

fn try_from(value: BlobMeta) -> Result<Self, Self::Error>

Performs the conversion.

impl Eq for BlobMeta

impl StructuralPartialEq for BlobMeta