hashtree-core

Simple content-addressed merkle tree with KV storage.

This is the core library that implements the merkle tree structure used by hashtree. It provides:

• SHA256 hashing
• MessagePack encoding for tree nodes (deterministic)
• CHK encryption by default (Content Hash Key)
• 2MB chunks by default (optimized for blossom uploads)

Usage

use hashtree_core::{HashTree, HashTreeConfig, store::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 = tree.put(b"Hello, World!").await?;

    // Read it back
    let data = tree.get(&cid, None).await?;

    Ok(())
}

Tree Nodes

Every stored item is either raw bytes or a tree node. Tree nodes are MessagePack-encoded with a type field:

• Blob (0) - Raw data chunk
• File (1) - Chunked file: links are unnamed, ordered by byte offset
• Dir (2) - Directory: links have names, may point to files or subdirs

Store Trait

The Store trait is just get(hash) → bytes and put(hash, bytes). Works with any backend that can store/fetch by hash.

Part of hashtree-rs.