LedgerMap

A secure, persistent key-value storage system with blockchain-like properties, implemented in Rust and compiled to WebAssembly.

Key Features

• 🔒 Secure Storage: Data integrity protected with SHA-256 checksums
• 📝 Append-Only Ledger: Blockchain-like data structure
• 🔄 Cross-Platform: Native support for wasm32, x86_64, and aarch64
• 🌐 Browser Ready: WebAssembly builds for browser environments
• 🏷️ Label Support: Organize data with multiple labels
• 📦 TypeScript Support: First-class TypeScript definitions

Quick Start

Rust Projects

# Cargo.toml
[dependencies]
ledger-map = "0.4.2"

use ledger_map::LedgerMap;

// Create a new ledger map
let mut map = LedgerMap::new_with_path(None, None)
    .expect("Failed to create LedgerMap");

// Store data
map.upsert("users", b"alice".to_vec(), b"data".to_vec())
    .unwrap();
map.commit_block().unwrap();

// Retrieve data
let value = map.get("users", &b"alice".to_vec());

Web/TypeScript Projects

npm install @decent-stuff/ledger-map

import { WasmLedgerMap } from "@decent-stuff/ledger-map";

// Initialize
const ledger = new WasmLedgerMap();
await ledger.initialize();

// Store data
const key = new TextEncoder().encode("alice");
const value = new TextEncoder().encode("data");

ledger.beginBlock();
ledger.upsert("users", key, value);
ledger.commitBlock();

// Retrieve data
const retrieved = ledger.get("users", key);

Installation

Rust

Add to your Cargo.toml:

[dependencies]
ledger-map = "0.4.2"

For specific features:

# For browser/WebAssembly support
ledger-map = { version = "0.4.2", features = ["browser"] }

# For Internet Computer support
ledger-map = { version = "0.4.2", features = ["ic"] }

Web/TypeScript

# Using npm
npm install @decent-stuff/ledger-map

# Using yarn
yarn add @decent-stuff/ledger-map

# Using pnpm
pnpm add @decent-stuff/ledger-map

Detailed Usage

Rust API

use ledger_map::{LedgerMap};
use env_logger::Env;

fn main() {
    // Initialize logging (optional)
    env_logger::try_init_from_env(Env::default().default_filter_or("info")).unwrap();

    // Create LedgerMap with optional custom storage path
    let mut ledger_map = LedgerMap::new_with_path(
        None,  // No specific labels to index
        None   // Use default storage path
    ).expect("Failed to create LedgerMap");

    // Store data with labels
    ledger_map.upsert("users", b"alice".to_vec(), b"data1".to_vec()).unwrap();
    ledger_map.upsert("posts", b"post1".to_vec(), b"content".to_vec()).unwrap();
    ledger_map.commit_block().unwrap();

    // Query by label
    let user_entries = ledger_map.iter(Some("users")).collect::<Vec<_>>();
    let post_entries = ledger_map.iter(Some("posts")).collect::<Vec<_>>();

    // Delete data
    ledger_map.delete("users", b"alice".to_vec()).unwrap();
    ledger_map.commit_block().unwrap();
}

TypeScript API

import { WasmLedgerMap } from "@decent-stuff/ledger-map";

async function example() {
  // Initialize
  const ledger = new WasmLedgerMap();
  await ledger.initialize(["users", "posts"]); // Pre-index labels

  // Store data
  const key = new TextEncoder().encode("user1");
  const value = new TextEncoder().encode(JSON.stringify({ name: "Alice" }));

  ledger.beginBlock();
  ledger.upsert("users", key, value);
  ledger.commitBlock();

  // Retrieve data
  const retrieved = ledger.get("users", key);
  const userData = JSON.parse(new TextDecoder().decode(retrieved));

  // Delete data
  ledger.beginBlock();
  ledger.delete("users", key);
  ledger.commitBlock();
}

API Reference

Rust API

• LedgerMap::new() - Create a new ledger map with default settings
• LedgerMap::new_with_path(labels: Option<&[&str]>, path: Option<PathBuf>) - Create with custom settings
• upsert(label: &str, key: Vec<u8>, value: Vec<u8>) - Store or update a value
• get(label: &str, key: &[u8]) -> Option<&Vec<u8>> - Retrieve a value
• delete(label: &str, key: Vec<u8>) - Delete a value
• commit_block() - Commit pending changes
• iter(label: Option<&str>) - Iterate over entries

TypeScript API

• initialize(labels?: string[]) - Initialize the ledger
• upsert(label: string, key: Uint8Array, value: Uint8Array) - Store or update a value
• get(label: string, key: Uint8Array) - Retrieve a value
• delete(label: string, key: Uint8Array) - Delete a value
• beginBlock() - Start a new block of operations
• commitBlock() - Commit the current block
• getBlocksCount() - Get total number of blocks
• getLatestBlockHash() - Get latest block hash
• refreshLedger() - Reload from storage

Contributing

We welcome contributions! Please see our Contributing Guidelines for details on how to:

• Set up the development environment
• Run tests
• Submit pull requests
• Follow our coding standards

Testing

Rust Tests

cargo test
cargo test --features browser
cargo test --features ic

TypeScript Tests

# Node.js tests
npm run test

# Browser tests
RUSTFLAGS='--cfg getrandom_backend="wasm_js"' wasm-pack test --chrome --features browser

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.