Struct PuffinReader 

pub struct PuffinReader<R: Read + Seek> { /* private fields */ }

Reader for Puffin files — parses the footer once, lazily loads blob payloads.

Examples

use std::io::Cursor;
use samkhya_core::puffin::{Blob, PuffinReader, PuffinWriter};

// Write a file in memory, then read it back.
let mut w = PuffinWriter::new(Cursor::new(Vec::<u8>::new()));
w.add_blob(Blob::new("samkhya.hll-v1", vec![1], b"sketch bytes")).unwrap();
let bytes = w.finish().unwrap().into_inner();

let mut reader = PuffinReader::open(Cursor::new(bytes)).unwrap();
let (idx, meta) = reader.find_blob("samkhya.hll-v1").unwrap();
assert_eq!(meta.kind, "samkhya.hll-v1");
assert_eq!(reader.read_blob(idx).unwrap(), b"sketch bytes");

Implementations

impl<R: Read + Seek> PuffinReader<R>

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

pub fn footer(&self) -> &FooterPayload

pub fn blobs(&self) -> &[BlobMetadata]

pub fn read_blob(&mut self, idx: usize) -> Result<Vec<u8>>

Read a blob’s payload by index.

pub fn read_blob_decompressed(&mut self, idx: usize) -> Result<Vec<u8>>

Read a blob’s payload by index and decompress it according to the blob’s compression_codec metadata.

Falls back to the raw bytes when the codec is None / unset. Returns an error if the recorded codec is unsupported in the current build (e.g. zstd without the zstd feature).

pub fn find_blob(&self, kind: &str) -> Option<(usize, &BlobMetadata)>

Find the first blob whose type (kind) matches kind.

Examples

use std::io::Cursor;
use samkhya_core::puffin::{Blob, PuffinReader, PuffinWriter};

let mut w = PuffinWriter::new(Cursor::new(Vec::<u8>::new()));
w.add_blob(Blob::new("samkhya.hll-v1", vec![0], b"x")).unwrap();
let bytes = w.finish().unwrap().into_inner();
let reader = PuffinReader::open(Cursor::new(bytes)).unwrap();
assert!(reader.find_blob("samkhya.hll-v1").is_some());
assert!(reader.find_blob("absent.kind").is_none());