Using Truffle

1. Install truffle (preferably v5.3.0+, sometimes with v5.1.33, @truffle/hdwallet-provider does not work)

npm install -g truffle

2. Create a metacoin project, unbox metacoin truffle box, and install @truffle/hdwallet-provider

mkdir truffle
cd truffle
truffle unbox truffle
npm install --save-dev @truffle/hdwallet-provider

3. Create deploy script ./migrations/1_deploy_contracts.js

const helloHyperasChain = artifacts.require("HelloHyperasChain");

module.exports = function(deployer) {
  deployer.deploy(helloHyperasChain)
      .then(() => helloHyperasChain.deployed())
      .then(_instance => console.log("helloHyperasChain deployed to:", _instance.address));

};

4. Modify truffle-config.js to add Hyperas Chain networks. Make sure to add your mnemonic or private key.

const HDWalletProvider = require('@truffle/hdwallet-provider');
const mnemonic = '<ADD-YOUR-MNEMONIC-HERE>';
const privateKeyTest = '<ADD-YOUR-PRIVATE-KEY-HERE>';

module.exports = {
  networks: {
    hyperaschain_testnet: {
      provider: () => {
        if (!privateKeyTest.trim()) {
          throw new Error(
              'Please enter a private key with funds, you can use the default one'
          );
        }
        return new HDWalletProvider({
          privateKeys: [privateKeyTest],
          providerOrUrl: 'https://vayne.hyperaschain.com/'// this is RPC for testnet shard 0 
        });
      },
      network_id: 140, // testnet
    },
  },
};

4. Compile and deploy

truffle compile
truffle deploy --network hyperaschain_testnet