How do I set a gasPrice with ethers deploy script?

Question

I'd like to set a gasPrice in my deploy script, so I could deploy and let miners pick up my transaction when gas is low. Like deploy my contract over night while I'm sleeping to save money.

How can I specify the gas price in my ethers deploy script?

   const MyContract = await ethers.getContractFactory('MyContract', signer);
   const mycontract = await MyContract.deploy();
   await mycontract.deployed();
   console.log('Deployed to:', mycontract.address);

Answer 1

You can override the options property of a transaction by adding an object as the last parameter:

 const mycontract = await MyContract.deploy({gasPrice: 50000000000}); // 50gwei

You can also specify a global gas price in your hardhat config. Something like this:

mainnet: {
   url: `https://mainnet.infura.io/v3/${InfuraKey}`, 
   gasPrice: 50000000000
}

Answer 2

After London Mainnet rollout, EIP-1559 changed how gas fees are calculated. Gas fees are now split into different components (block-based base fee + tip) and a transaction issuer can specify a max fee/tip that he is willing to pay.

For ethers this means calling getFeeData instead of getGasPrice and passing it as an option to the deploy method.

// The gas price (in wei)...
const feeData = await provider.getFeeData();
// {
//   gasPrice: { BigNumber: "23610503242" },
//   maxFeePerGas: { BigNumber: "46721006484" },
//   maxPriorityFeePerGas: { BigNumber: "1500000000" }
// }

const MyContract = await ethers.getContractFactory('MyContract', signer);
const mycontract = await MyContract.deploy(feeData);
await mycontract.deployed();
console.log('Deployed to:', mycontract.address);

To get more readable values you can format in gwei.

utils.formatUnits(feeData.maxFeePerGas, 'gwei');
// '46.721006484'