the-loooootery

About

An on-chain lottery game where users buy the ticket for a flat fee. Winner is chosen randomly and all funds in the contract are paid out to the winner! Are you brave enough to take a ride on the dev

Website: https://the-loooootery-k2qwpqio1-zrowgz.vercel.app/
Contract Address: 0x0E221b24AA33762D1Cc5B75Bb50d1B43cc72853a

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Use

Game play where users buy a ticket and take the ride! A random soul is selected to inherit the fortunes of the other lost souls...

Function Definitions

Publicly Available Functions

• buyTicket: user sends funds to contract and is added to the drawing
• getTicketPrice: obtain the ticket price in wei
• getHouse, getBalance, getRiderCount, getRiders: all display current game parameters
• getWinner: returns the most recent winner address

Publicly Callable Variables

• fee: fee paid to chainlink VRF in $LINK in wei
• maxRiders, owner, riders, ticketPrice: current game stats and parameters
• ticketSales, tripsTaken: historical data

Admin/onlyOwner

Note: the House address should be set to a multisig to reduce the risk of abuse for emergency functions!

• emergencyRefund: returns funds to users
• emergencyReboot: if contract locks up due to an out of gas error at one of the EOAs, withdraws all funds to House & resets state
• setAcceptingRiders: a way to pause the contract
• setFee & setKeyHash: updatable settings for Chainlink VRF
• setTicketPrice, setMaxRiders, setHouse: adjusts parameters for the game

Contract-Only Functions

• getRandomNumber: when maxRiders are met, call this to trigger VRF call. Only called internally.
• fulfillRandomness: only callable by Chainlink VRF Coordinator
  • Assigns winner
  • Pays out winnings
  • Reset's the contract state for next round

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Installation & Requirements

Requirements

warning: using sudo when installing node & it's components may result in permissions issues

• npm
• nodejs version 16
• npx
• git

You will need to obtain:

• API keys for access to Rinkeby (alchemy?)
• The private key (not seedphrase) from your ethereum wallet
• Access to Rinkeby Testnet
• Some Rinkeby test ether

Replace sample.env fields with your own data and save as .env

To install the repo, download the repository using

git clone https://github.com/ZrowGz/the-loooootery.git

Then, from the CLI at the root of this new directory run each:

• npm install
• npx hardhat compile
• npx hardhat run --network rinkeby scripts/DevilTrainLotto/deploy.js;
• npm run dev

To deploy to a website, you will need to first run:

• npm run build
• Resolve any build errors
• Then connect your github to a service like Vercel

To verify your smart contract code on the blockchain scanner:

• obtain an etherscan API Key
• install the plugin using: npm install @nomiclabs/hardhat-etherscan
• modify hardhat.config.js
  • below the existing require() add: require(”@nomiclabs/hardhat-etherscan”);
• modify module.exports:

module.exports = {
  solidity: "0.8.7", 
  networks: {
    rinkeby: {
      url: secrets.url,
      accounts: [secrets.key]
    }
  },
  etherscan: {
    apiKey: "YOUR_ETHERSCAN_API_KEY_HERE"
  }
};

• create secrets.json
• NEEDS TO BE COMPLETED - CONTRACT SOURCE CODE REMAINS UNVERIFIED

Open a web browser and navigate to: localhost:3000

• Can also verify deployement using: npx hardhat verify --network ropsten DEPLOYED_CONTRACT_ADDRESS <--Replace this with your deployed contract's address

hardhat-nextjs-mui-starter

A starter app with hardhat, nextjs, and mui.

Advanced Sample Hardhat Project

This project demonstrates an advanced Hardhat use case, integrating other tools commonly used alongside Hardhat in the ecosystem.

The project comes with a sample contract, a test for that contract, a sample script that deploys that contract, and an example of a task implementation, which simply lists the available accounts. It also comes with a variety of other tools, preconfigured to work with the project code.

Try running some of the following tasks:

npx hardhat accounts
npx hardhat compile
npx hardhat clean
npx hardhat test
npx hardhat node
npx hardhat help
REPORT_GAS=true npx hardhat test
npx hardhat coverage
npx hardhat run scripts/deploy.js
node scripts/deploy.js
npx eslint '**/*.js'
npx eslint '**/*.js' --fix
npx prettier '**/*.{json,sol,md}' --check
npx prettier '**/*.{json,sol,md}' --write
npx solhint 'contracts/**/*.sol'
npx solhint 'contracts/**/*.sol' --fix

Etherscan verification

To try out Etherscan verification, you first need to deploy a contract to an Ethereum network that's supported by Etherscan, such as Ropsten.

In this project, copy the .env.example file to a file named .env, and then edit it to fill in the details. Enter your Etherscan API key, your Ropsten node URL (eg from Alchemy), and the private key of the account which will send the deployment transaction. With a valid .env file in place, first deploy your contract:

hardhat run --network ropsten scripts/deploy.js

Then, copy the deployment address and paste it in to replace DEPLOYED_CONTRACT_ADDRESS in this command:

npx hardhat verify --network ropsten DEPLOYED_CONTRACT_ADDRESS "Hello, Hardhat!"

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Addresses & Links

This Contract

Rinkeby Contract Address: 0x0E221b24AA33762D1Cc5B75Bb50d1B43cc72853a

On Rinkeby Testnet

Website: https://the-loooootery-k2qwpqio1-zrowgz.vercel.app/
Contract Address: 0x0E221b24AA33762D1Cc5B75Bb50d1B43cc72853a
House Multisig (gnosis safe): 0x1DfF53Bbb4D478161dF0b0D51B8Bc942108bE055

Chainlink Data

VRF Addresses: https://docs.chain.link/docs/vrf-contracts/
LINK & ETH Faucet: https://faucets.chain.link/rinkeby

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Contributors

• Eamon Conheady - github: ZrowGz
• Meghan Kennedy - github: megkennedy
• Will Dittig - github: WillDittig
• Athit Padmasuta - github: AthitXX