HashTree - Simple content-addressed merkle tree storage

Rust-first library for building merkle trees with content-hash addressing: SHA256(content) -> content

Overview

HashTree provides a simple, efficient way to build and traverse content-addressed merkle trees. It uses SHA256 for hashing and MessagePack for tree node encoding.

Content is CHK (Content Hash Key) encrypted by default, enabling deduplication even for encrypted content. Use .public() config to disable encryption.

Core Concepts

• Blobs: Raw data stored directly by their hash (SHA256(data) -> data)
• Tree Nodes: MessagePack-encoded nodes with links to children (SHA256(msgpack(node)) -> msgpack(node))
• Links: References to child nodes with optional name and size metadata
• Cid: Content identifier with hash + optional encryption key

Example

use hashtree_core::{HashTree, HashTreeConfig, MemoryStore};
use std::sync::Arc;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let store = Arc::new(MemoryStore::new());
    let tree = HashTree::new(HashTreeConfig::new(store));

    // Store content (encrypted by default)
    let (cid, _size) = tree.put(b"Hello, World!").await?;

    // Read it back
    let data = tree.get(&cid).await?;
    assert_eq!(data, Some(b"Hello, World!".to_vec()));

    Ok(())
}