🛠️ RenJS

The official Javascript SDK for interacting with RenVM.

Links

• Developer Docs
• Getting Started Tutorial
• ChaosDEX, a cross-chain DEX

Installation

Install RenJS using Yarn/npm:

yarn add @renproject/ren

or

npm install --save @renproject/ren

Importing RenJS

Importing using require syntax

const RenJS = require("@renproject/ren").default;

Importing using ES6 syntax

import RenJS from "@renproject/ren";

Usage

Usage is described in the getting started tutorial.

Example of bridging BTC into Ethereum:

// ... web3 is initialized

const renJS = new RenJS("testnet"); // or "chaosnet"

const amount = 0.001; // testnet BTC

const shiftIn = renJS.shiftIn({
    // Send BTC from the Bitcoin blockchain to the Ethereum blockchain.
    sendToken: RenJS.Tokens.BTC.Btc2Eth,

    // Amount of BTC we are sending (in Satoshis)
    sendAmount: Math.floor(amount * (10 ** 8)), // Convert to Satoshis

    // The contract we want to interact with
    sendTo: "0xb2731C04610C10f2eB6A26ad14E607d44309FC10",

    // The name of the function we want to call
    contractFn: "deposit",

    // Arguments expected for calling `deposit`
    contractParams: [
        {
            name: "_msg",
            type: "bytes",
            value: web3.utils.fromAscii(`Depositing ${amount} BTC`),
        }
    ],
});

const gatewayAddress = shiftIn.addr();
this.log(`Deposit ${amount} BTC to ${gatewayAddress}`);

await shiftIn.waitAndSubmit(web3.currentProvider, 0 /* confirmations */);

Example of bridging BTC out of Ethereum:

// ... zBTC is burnt in the Ethereum transaction `txHash`

const renJS = new RenJS("testnet"); // or "chaosnet"

const shiftOut = await renJS.shiftOut({
    // Send BTC from the Ethereum blockchain to the Bitcoin blockchain.
    sendToken: RenJS.Tokens.BTC.Eth2Btc,

    // The web3 provider to talk to Ethereum
    web3Provider: web3.currentProvider,

    // The transaction hash of our contract call
    txHash,
}).readFromEthereum();

await shiftOut.submitToRenVM();

Developer notes

Building

yarn run watch
# or
yarn run build

Running tests

You'll need to:

1. Generate a mnemonic and send ETH (kovan for testnet) (path: m/44'/60'/0'/0/)
2. Generate a private key and send BTC and ZEC (tBTC and TAZ for testnet)
3. Generate an Infura API key

Create a .env file which contains the following exported variables:

export MNEMONIC="your mnemonic here"
export TESTNET_BITCOIN_KEY="your bitcoin private key (encoded in WIF)"
export INFURA_KEY="your infura key (for it's v3 endpoint)"
export NETWORK="mainnet or testnet"

Then just run the following command to execute the tests. Make sure there is sufficient Kovan ETH in the linked account before running tests.

yarn run test

Update contract bindings

In order to update the bindings in src/contracts/bindings, you need to clone darknode-sol and run:

yarn run bindings:ts