Solidity Voting Contract

This contract comes from Solidity by Example. In addition to the example, I added some getter functions to further expand on the example.

Installation

npm install

Compiling Solidity

npx hardhat compile

Running tests

npx hardhat test

Deploying Contract on Local Network

First, start a local node in a separate terminal window:

npx hardhat node

Next, deploy the contract to the local node:

npx hardhat run scripts/deploy.js --network localhost

NOTE: The deploy script defines a bytes32 array that is passed to the contract constructor. The string values of the array are: dog, cat, penguin, frog.

Make sure to get the contract address from the output after the deployment has finished.

Vote

Finally, start a console on the local network:

npx hardhat console --network localhost

Instantiate the contract and attach to the contract address:

// Instantiate token object and attach to contract address
const Ballot = await ethers.getContractFactory("Ballot");
const ballot = Ballot.attach("<CONTRACT ADDRESS>");

// Get owner account address and other addresses
const [owner, addr1, addr2, addr3, addr4, ...addrs] = await ethers.getSigners();

Give address right to vote and then have those addresses vote or delegate their vote

// Give right to vote to addr1, addr2, addr3, addr4
await ballot.giveRightToVote(addr1.address);
await ballot.giveRightToVote(addr2.address);
await ballot.giveRightToVote(addr3.address);
await ballot.giveRightToVote(addr4.address);

// Delegate vote for addr1 and addr2 to addr3
await ballot.connect(addr1).delegate(addr2.address);
await ballot.connect(addr2).delegate(addr3.address);

// Have addr3 and addr4 vote
await ballot.connect(addr3).vote(1);
await ballot.connect(addr4).vote(2);

Lastly, when voting is done, calculate winning proposal:

const winningProposal = await ballot.winnerName();

// Convert bytes32 to string
const proposalName = ethers.utils.parseBytes32String(winningProposal);
console.log(proposalName);  // logs 'cat'