horizontalsystems / atomic-swap-kit-ios

Atomic Swap iOS library for Bitcoin (BTC) and Bitcoin Cash (BCH) swaps in decentralized manner. Implemented on Swift.

Overview

This is a swift library that allows Atomic Swap, decentralized crypto currency exchange, between 2 parties. The implementation is based on Hash Time Locked Contracts.

Usage

Initialization

The primary class to use is SwapKit.

import BitcoinKit
import BitcoinCashKit
import AtomicSwapKit

let swapKit = SwapKit.instance()

swapKit.register(blockchainCreator: BitcoinSwapBlockchainCreator(kit: bitcoinAdapter.bitcoinKit), forCoin: "BTC")
swapKit.register(blockchainCreator: BitcoinSwapBlockchainCreator(kit: bitcoinCashAdapter.bitcoinCashKit), forCoin: "BCH")
swapKit.load()

The supported coins should be registered to SwapKit. The load method resumes atomic swaps previously in progress.

Exchanging crypto-curencies

There are 2 sides that take part in the process: Initiator and Responder. The process consists of the following steps:

Request for a swap

Initiator creates swap request:

let swapRequest = try swapKit.createSwapRequest(haveCoinCode: "BTC", wantCoinCode: "BCH", rate: 0.2, amount: 0.5)

Response to a swap

Responder creates response for this request:

let swapResponse = swapKit.createSwapResponse(from: swapRequest)

Creating response also starts the swap process in the Responder side.

Initiate swap

Initiator takes response and starts the swap

swapKit.initiateSwap(from: swapResponse)

Initiator and Responder Communication

The Swap Request and Swap Response are the simple data objects. They can be easily serialized into/parsed from strings and interchanged via standard apps, like messenger or email.

Prerequisites

• Xcode 10.0+
• Swift 5+
• iOS 11+

Installation

CocoaPods

CocoaPods is a dependency manager for Cocoa projects. You can install it with the following command:

$ gem install cocoapods

CocoaPods 1.5.0+ is required to build BitcoinKit.

To integrate BitcoinKit into your Xcode project using CocoaPods, specify it in your Podfile:

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '11.0'
use_frameworks!

target '<Your Target Name>' do
  pod 'AtomicSwapCore.swift'
  pod 'AtomicSwapBitcoinProvider'
end

Then, run the following command:

$ pod install

Example Project

All features of the library are used in example project. It can be referred as a starting point for usage of the library.

• Example Project

Dependencies

• HSHDWalletKit - HD Wallet related features, mnemonic phrase geneartion.
• HSCryptoKit - Crypto functions required for working with blockchain.

License

The AtomicSwapKit-iOS toolkit is open source and available under the terms of the MIT License.