Main Contract

Example code minting BPros without Truffle

In the following example we will learn how to:
  • Use the ABIs of Money on Chain.
  • Get the maximum amount of BPRO available.
  • Get the price of the BPRO in RBTC.
  • Minting BPROs
We will use the testnet network
First we create a new node project.
mkdir example-mint-bpro
cd example-mint-bpro
npm init
Let's add the necessary dependencies to run the project.
npm install --save bignumber.js
npm install --save web3
npm install --save truffle-hdwallet-provider
Now we create a new script called mintBpro.js with the following code:
const HDWalletProvider = require('truffle-hdwallet-provider');
const BigNumber = require('bignumber.js');
const Web3 = require('web3');
//You must compile the smart contracts or use the official ABIs of the repository
const MocAbi = require('./contracts/moc/MoC.json');
const MoCInrateAbi = require('./contracts/moc/MoCInrate.json');
const MoCExchangeAbi = require('./contracts/moc/MoCExchange.json');
const MoCStateAbi = require('./contracts/moc/MoCState.json');
//Config params to TestNet
const endpoint = '';
//a mnemonic is 12 words instead of a single private key to sign the //transactions
const mnemonic = 'chase chair crew elbow uncle awful cover asset cradle pet loud puzzle';
const provider = new HDWalletProvider(mnemonic, endpoint);
const web3 = new Web3(provider);
//Contract addresses on testnet
const mocContractAddress = '<contract-address>';
const mocInrateAddress = '<contract-address>';
const mocExchangeAddress = '<contract-address>';
const mocStateAddress = '<contract-address>';
const gasPrice = 60000000;
const execute = async () => {
* Loads an specified contract
* @param {json ABI} abi
* @param {localhost/testnet/mainnet} contractAddress
const getContract = async (abi, contractAddress) => new web3.eth.Contract(abi, contractAddress);
* Transforms BigNumbers into
* @param {*} number
const toContract = number => new BigNumber(number).toFixed(0);
// Loading moc contract
const moc = await getContract(MocAbi.abi, mocContractAddress);
if (!moc) {
throw Error('Can not find MoC contract.');
// Loading mocInrate contract. It is necessary to get fees for transaction types
const mocInrate = await getContract(MoCInrateAbi.abi, mocInrateAddress);
if (!mocInrate) {
throw Error('Can not find MoC Inrate contract.');
// Loading mocExchange contract. It is necessary to compute commissions and vendor markup
const mocExchange = await getContract(MoCExchangeAbi.abi, mocExchangeAddress);
if (!mocExchange) {
throw Error('Can not find MoC Exchange contract.');
// Loading mocState contract. It is necessary to compute max BPRO available to mint
const mocState = await getContract(MoCStateAbi.abi, mocStateAddress);
if (!mocState) {
throw Error('Can not find MoCState contract.');
const mintBpro = async (btcAmount, vendorAccount) => {
const from = '0x088f4B1313D161D83B4D8A5EB90905C263ce0DbD';
const weiAmount = web3.utils.toWei(btcAmount, 'ether');
let btcCommission;
let mocCommission;
let btcMarkup;
let mocMarkup;
// Set transaction types
const txTypeFeesRBTC = await mocInrate.methods.MINT_BPRO_FEES_RBTC();
const txTypeFeesMOC = await mocInrate.methods.MINT_BPRO_FEES_MOC();
// Compute fees
const params = {
account: from,
amount: toContractBN(weiAmount).toString(),
txTypeFeesMOC: txTypeFeesMOC.toString(),
txTypeFeesRBTC: txTypeFeesRBTC.toString(),
} = await mocExchange.methods.calculateCommissionsWithPrices(params, { from }));
// Computes totalBtcAmount to call mintBpro. If commission is paid in RBTC, add it to value
const totalBtcAmount = toContract(;
console.log(`Calling Bpro minting with account: ${from} and amount: ${weiAmount}.`);
const tx = moc.methods
.mintBProVendors(weiAmount, vendorAccount)
.send({ from, value: totalBtcAmount, gasPrice }, function(error, transactionHash) {
if (error) console.log(error);
if (transactionHash) console.log('txHash: '.concat(transactionHash));
return tx;
function logEnd() {
console.log('End Example');
const btcAmount = '0.00005';
const vendorAccount = '<vendor-address>';
// Call mint
await mintBpro(btcAmount, vendorAccount, logEnd);
.then(() => console.log('Completed'))
.catch(err => {
console.log('Error', err);