Hardhat deployment scripts in Blockchain / Solidity - Step-by-Step Execution

Concept Flow - Hardhat deployment scripts

Start script

↓

Load Hardhat Runtime Environment

↓

Get contract factory

↓

Deploy contract

↓

Wait for deployment

↓

Log deployed address

↓

End script

The deployment script loads Hardhat, prepares the contract, deploys it, waits for confirmation, then logs the address.

Execution Sample

Blockchain / Solidity

async function main() {
  const hre = require('hardhat');
  const Contract = await hre.ethers.getContractFactory("MyContract");
  const contract = await Contract.deploy();
  await contract.deployed();
  console.log("Deployed to:", contract.address);
}
main();

This script deploys 'MyContract' to the blockchain and prints its address.

Execution Table

Step	Action	Evaluation	Result
1	Load Hardhat Runtime Environment (hre)	hre.ethers available	Ready to interact with contracts
2	Get contract factory for 'MyContract'	hre.ethers.getContractFactory('MyContract')	Contract factory object obtained
3	Deploy contract	Contract.deploy()	Deployment transaction sent
4	Wait for deployment to complete	contract.deployed()	Contract deployed and address assigned
5	Log deployed contract address	console.log(contract.address)	Address printed to console
6	Script ends	No further actions	Deployment complete

💡 Script ends after logging deployed contract address

Variable Tracker

Variable	Start	After Step 2	After Step 3	After Step 4	Final
hre	undefined	Hardhat Runtime Environment object	Same	Same	Same
Contract	undefined	Contract factory for MyContract	Same	Same	Same
contract	undefined	undefined	Deployment transaction object	Deployed contract instance with address	Same

Key Moments - 3 Insights

Why do we use 'await' before deploy() and deployed()?

Because deploy() sends a transaction that takes time to confirm, and deployed() waits until the contract is fully deployed. See execution_table steps 3 and 4.

What is the contract factory and why do we need it?

The contract factory is like a blueprint to create new contract instances. We get it in step 2 to prepare deployment.

Why do we log contract.address after deployment?

Because the address is only assigned after deployment completes (step 4), so logging it before would be undefined.

Visual Quiz - 3 Questions

Look at the execution table, what is the value of 'contract' after step 3?

A Deployment transaction object

B Contract factory object

C Deployed contract instance with address

D Undefined

💡 Hint

Check variable_tracker row for 'contract' after Step 3

At which step does the script wait for the contract to be fully deployed?

A Step 2

B Step 4

C Step 3

D Step 5

💡 Hint

See execution_table action 'Wait for deployment to complete'

If we remove 'await' before contract.deployed(), what happens?

A Script waits correctly for deployment

B Deployment will fail

C contract.address will be undefined when logged

D Script will throw a syntax error

💡 Hint

Refer to key_moments about why 'await' is needed before deployed()

Concept Snapshot

Hardhat deployment script steps:
1. Load Hardhat Runtime Environment (hre)
2. Get contract factory with hre.ethers.getContractFactory('ContractName')
3. Deploy contract with await deploy()
4. Wait for deployment with await deployed()
5. Log deployed contract address
Use async/await to handle asynchronous blockchain operations.

Full Transcript

This visual execution shows how a Hardhat deployment script runs step-by-step. First, the script loads the Hardhat Runtime Environment (hre) to access blockchain tools. Then it gets a contract factory for the contract named 'MyContract'. Next, it deploys the contract by sending a transaction and waits for the deployment to complete. After deployment, the contract address is available and logged to the console. Variables like 'contract' change from undefined to a deployment transaction object, then to a deployed contract instance with an address. Key points include using 'await' to wait for asynchronous steps and logging the address only after deployment finishes. The quiz tests understanding of these steps and variable states.