Liquid Wallet Kit - react native

LWK-rn is a React Native module for Liquid Wallet Kit. Its goal is to provide all the necessary building blocks for mobile development of a liquid wallet.

NOTE: LWK and LWK-rn is in public beta and still undergoing significant development. Use it at your own risk.

Please consider reviewing, experimenting and contributing

Thanks for taking a look!

Installation

Using npm:

npm install lwk-rn

Using yarn:

yarn add lwk-rn

Note: Use android sdk version >= 24 and iOS >= v13 .

Usage

Import LWK-rn library

import { Mnemonic, Network, Signer, Wollet } from 'lwk-rn';

Create a signer for a mnemonic and a network

let mnemonic = new Mnemonic("abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"); 
let network = Network.testnet();
let signer = new Signer(mnemonic, network);
console.log(mnemonic.toString());

Create and update a wollet from the signer descriptor

let singlesigDesc = signer.wpkhSlip77Descriptor();
let wollet = new Wollet(network, singlesigDesc, undefined);
let client = network.defaultElectrumClient();
let update = client.fullScan(wollet);
if (update) { 
  wollet.applyUpdate(update);
}

Get a new unused address

let latest_address = wollet.address(undefined); 
console.log(latest_address.address().scriptPubkey().toString());

Get balance as [AssetId : UInt64]

let balance = wollet.balance();
console.log(balance);
for (var b of balance.entries()) {
  console.log("asset: ", b[0], ", value: ", b[1]);
}

Get a transaction list

let txs = wollet.transactions();
console.log(txs);
for (var tx of txs) {
  for (var output of tx.outputs()) {
    let script_pubkey = output?.scriptPubkey().toString();
    let value = output?.unblinded().value().toString();
    console.log("script_pubkey: ", script_pubkey, ", value: ", value);
  }
}

Build, sign, finalize and broadcast a transaction of policy asset

let latest_address = wollet.address(undefined);
let out_address = latest_address.address();
let satoshis = 900n;
let fee_rate = 280; // this seems like absolute fees
let builder = network.txBuilder();
builder.addLbtcRecipient(out_address, satoshis);
builder.feeRate(fee_rate);
let pset = builder.finish(wollet);
let signed_pset = signer.sign(pset);
let finalized_pset = wollet.finalize(signed_pset);
let txid = client
    .broadcast(finalized_pset.extractTx());
console.log("BROADCASTED TX!\nTXID: ", txid);

Build, sign, finalize and broadcast a transaction of liquid asset

let latest_address = wollet.address(undefined);
let out_address = latest_address.address();
let satoshis = 900n;
let fee_rate = 280; // this seems like absolute fees
let builder = network.txBuilder();
builder.addLbtcRecipient(out_address, satoshis);
builder.feeRate(fee_rate);
// sign and send
let pset = builder.finish(wollet);
let signed_pset = signer.sign(pset);
let finalized_pset = wollet.finalize(signed_pset);
let txid = client.broadcast(finalized_pset.extractTx());
console.log("BROADCASTED TX!\nTXID: ", txid.toString());

Build, sign, finalize and broadcast a transaction of liquid asset

let builder = network.txBuilder();
let asset = '0f1040289a4e88e6acef89b65ce4847b6fd68ac39b89fa978bf23e2c039f5e27';
builder.addRecipient(out_address, 100n, asset);
builder.feeRate(fee_rate);
let pset = builder.finish(wollet);
let signed_pset = signer.sign(pset);
let finalized_pset = wollet.finalize(signed_pset);
let txid = client.broadcast(finalized_pset.extractTx());
console.log("BROADCASTED TX!\nTXID: ", txid.toString());

Build

LWK-rn repository contains the pre-generated lwk bindings for android and ios.

Follow the steps to generate bindings by your own:

Install C++ tooling

# For MacOS, using homebrew:
brew install cmake ninja clang-format
# For Debian flavoured Linux:
apt-get install cmake ninja clang-format

Add the Android specific targets

rustup target add \
    aarch64-linux-android \
    armv7-linux-androideabi \
    i686-linux-android \
    x86_64-linux-android
# Install cargo-ndk
cargo install cargo-ndk

Add the iOS specific targets

rustup target add \
    aarch64-apple-ios \
    aarch64-apple-ios-sim \
    x86_64-apple-ios
# Ensure xcodebuild is available
xcode-select --install

Install deps and uniffi-bindgen-react-native.

$ yarn install

Fetch LWK library with some hacks.

The script changes path to avoid using workspace configuration and rust version. The project require rust >= v1.18 . The scipt replacing package name in Cargo.toml for a library name bug in uniffi-bindgen-react-native.

$ sh fetch_lwk.sh

Generate bindings for android and ios:

$ yarn ubrn:android
$ yarn ubrn:ios

Example

Open demo application in ./example/ folder and read the code in ./example/src/App.tsx .

You could run the example on the Android demo app on device/emulator by:

$ yarn example android

Or you could run the iOS demo app by:

$ cd example
$ bundle install
$ bundle exec pod install # every time you update your native dependencies
$ cd ..
$ yarn example ios

Contributing

See the contributing guide to learn how to contribute to the repository and the development workflow.

HOWTO

See the how-to to learn how works lwk-rn react native module and the repo code.

Greetings

Thanks to all Blockstream LWK team for the amazing library.

A special thanks to @rcasatta to help me about packaging library for iOS and Android.

A big thanks to @BlakeKaufman because give me the opportunity to build this library with a Bounty and made contributions by itself.

License

MIT

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Made with create-react-native-library using uniffi-bindgen-react-native