A module for using Qtum through an Ethers compliant library to make it simpler to use Qtum
TLDR: Breaking change in gas price, if you hardcode gas price then update your code otherwise you are probably ok upgrading to this version
This version has a breaking change in gas price Janus has a bug in eth_gasPrice that returns GWEI instead of WEI If you have hardcoded gas price in your code, you will need to update it from 0x9502f9000 to 0x5d21dba000 If you rely on eth_gasPrice then nothing else should be required
This release also works around the bug in Janus and will detect when it is fixed and act correctly The worst case scenario to not upgrading to this release is when the Janus server you talk to gets upgrade your transactions will have higher transaction fees as eth_gasPrice will return a larger number
Keep in mind that Qtum rejects transactions with absurdly high transaction fees, so the network will prevent accidental out of control spending by rejecting transactions - though this bug will not increase fees anywhere near that
We will be deploying bugfixed Janus to our mainnet server fleet
This release also improves transaction fee calculation and will result in lower transaction fees
Upgrading to this version will warn you when creating transactions with Janus instances that have not been upgraded after May 30th, 2022
After August 1st 2022, the warnings will turn into errors and you will be unable to create transactions with old Janus instances
public key address generation now follows QTUM behavior, the same private keys will now generate different addresses
adds support for importing WIF private keys
gas price is now specified in WEI, not Satoshis
Open a console and run
npm install qtum-ethers-wrapper
import {Contract} from "ethers"
import {
QtumProvider as Provider,
QtumWallet as Wallet,
QtumContractFactory as ContractFactory,
QTUM_BIP44_PATH, // Compatible with Qtum core wallet and electrum
SLIP_BIP44_PATH // Compatible with 3rd party wallets
} from "qtum-ethers-wrapper";
// point Qtum Provider at Janus node https://github.com/qtumproject/janus/
const mainnetProvider = new Provider("https://janus.qiswap.com/api/");
const testnetProvider = new Provider("https://testnet-janus.qiswap.com/api/");
// or deploy your own node locally with a regtest network
// see for a pre-built docker image https://hub.docker.com/r/ripply/janus
const regtestProvider = new Provider("http://localhost:23889");
const provider = testnetProvider;
// create a wallet
const privkey = "99dda7e1a59655c9e02de8592be3b914df7df320e72ce04ccf0427f9a366ec6e"
const signer = new Wallet(
privkey,
provider,
{
filterDust: true, // optional, will default to true in a future release
}
)
// or create a random account and get the mnemonic
// const signer = Wallet.createRandom(/*{ path = SLIP_BIP44_PATH }*/}).connect(provider);
// const {locale, path, phrase} = signer._mnemonic();
// QRC20 ABI
const ABI = [{"constant":true,"inputs":[],"name":"name","outputs":[{"name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_value","type":"uint256"}],"name":"approve","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"totalSupply","outputs":[{"name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"name":"_from","type":"address"},{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transferFrom","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"name":"","type":"uint8"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"name":"_owner","type":"address"}],"name":"balanceOf","outputs":[{"name":"balance","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transfer","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[{"name":"_owner","type":"address"},{"name":"_spender","type":"address"}],"name":"allowance","outputs":[{"name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"payable":true,"stateMutability":"payable","type":"fallback"},{"anonymous":false,"inputs":[{"indexed":true,"name":"owner","type":"address"},{"indexed":true,"name":"spender","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"from","type":"address"},{"indexed":true,"name":"to","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Transfer","type":"event"}];
// https://github.com/qtumproject/janus/blob/master/playground/pet-shop-tutorial/contracts/QRC20Token.sol
const BYTECODE = "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"
// QtumContractFactory is required to be used instead of standard ethers ContractFactory due to how contract addresses are computed differently
const simpleStore = new ContractFactory(ABI, BYTECODE, signer);
// simpleStore deployment example, returns address
async function deployToken() {
const deployment = await simpleStore.deploy({
gasLimit: "0x7a120", // 500,000
gasPrice: "0x5d21dba000" // in WEI, not Satoshis
});
await deployment.deployed();
return deployment.address
}
// connect to QRC20 token and interact with it
async function transferToken(contractAddress, from, to, value) {
const qrc20 = new Contract(contractAddress, QRC_ABI, signer)
const name = await qrc20.transfer(from, to, value,
{
gasLimit: "0x62521", // 62521
gasPrice: "0x5d21dba000", // in WEI, not Satoshis
}
);
}
const contractAddress = await deployToken();
await transferToken(contractAddress, "0x...", "0x...", 1);- Issues
Qtum estimate gas function is not perfect so eth_estimateGas has a 20% buffer for gas limit
Janus doesn't return a transaction receipt for p2pkh tx's
This extension works with p2pkh scripts only and asks Janus for p2pkh scripts only