Smart Lottery contract (VYPER)

This is the VYPER version of the repository, you also can find a SOLIDITY version

This is a repository to work with and create a lottery game name Smart Lottery in a javascript environment using hardhat. This is a backend repository, it also work with a frontend repository. However you absolutly can use this repository without the frontend part.

Summary

Version 1

The Smart Lottery contract V1 creates a simple lottery which will picked a random winner once the lottery end. The constructor takes an interval (time of duration of the lottery) and and usd entrance fee (entrance fee in dollars).

This contract implements :

• Chainlink Keeper to trigger when the lottery must end.
• Chainlink VRF to pick a random winner when the lottery ends.
• Chainlink price feed to know the entrance fee value in ETH.

The Smart Lottery allow you to :

• enterLottery: Enter the lottery by paying entrance fees (USD convert to ETH).
• claimRewards: Get rewards of the previous lotteries you won.
• getWinner: Get any winner of a previous lottery thanks to the lottery number.
• getLotteryBalance: Get any pot size of a previous lottery thanks to the lottery number.

Version 2

The Smart Lottery contract V2 creates a ticket lottery which will picked a random winning ticket once the lottery end. The constructor takes an interval (time of duration of the lottery), an usd entrance fee (entrance fee in dollars) and a prize distribution corresponding on the percentage of each pots.

This contract implements :

• Chainlink Keeper to trigger when the lottery must end.
• Chainlink VRF to pick a random winner when the lottery ends.
• Chainlink price feed to know the ticket fee value in ETH.

The Smart Lottery V2 allow you to :

• buyTickets: Buy tickets to play the lottery by paying ticket fees (USD convert to ETH) - Max 10 tickets.

• revealWinningTickets: Reveal if you have winning tickets among all the tickets you buy.

• claimRewards: Get rewards of the previous lotteries where you get matching tickets.

• getWinningTicket: Get any winning tickets of a previous lottery thanks to the lottery number.

• getLotteryBalance: Get any pot size of a previous lottery thanks to the lottery number.

• Smart Lottery

  • Summary
  • Prerequisites
  • Installation
  • Testnet Development

• Usage

  • Deployment
  • Testing

Prerequisites

Please install or have installed the following:

• git
• nodejs and npm

Installation

1. Clone this repository

git clone https://github.com/jrmunchkin/smart-lottery-vyper
cd smart-lottery-vyper

2. Install dependencies

yarn

Testnet Development

If you want to be able to deploy to testnets, do the following. I suggest to use goerli network.

cp .env.example .env

Set your GOERLI_RPC_URL, and PRIVATE_KEY

You can get a GOERLI_RPC_URL by opening an account at Alchemy. Follow the steps to create a new application.

You also can work with Infura.

You can find your PRIVATE_KEY from your ethereum wallet like metamask.

If you want to use it with the frontend repository, You also can clone it and set your frontend path FRONT_END_FOLDER

the UPDATE_FRONT_END set to true will update your frontend with the last deployed contract.

Finally you can add a COINMARKETCAP_API_KEY if you want to use hardhat gas reporter. You can find one by registring to CoinMarketCap Developers.

You can add your environment variables to the .env file:

PRIVATE_KEY=<PRIVATE_KEY>
GOERLI_RPC_URL=<RPC_URL>
COINMARKETCAP_API_KEY=<YOUR_API_KEY>
FRONT_END_FOLDER=<YOUR_PATH_TO_FRONTEND>
UPDATE_FRONT_END=<TRUE_OR_FALSE>

You'll also need testnet goerli ETH if you want to deploy on goerli tesnet. You can get ETH into your wallet by using the alchemy goerli faucet or chainlink faucet.

Usage

Deployment

Feel free to change the interval variable in the helper-hardhat-config.js if you want your lottery interval to be more than 60 seconds.

You also can change the value of usdEntranceFee for setting your lottery entrance fee or ticket fee for V2.

For the lottery V2 you also can set the prizeDistribution of the different pots.

To deploy the contracts locally

yarn hardhat deploy

To deploy on goerli tesnet you need to create first a subscription on Chainlink VRF. Add the newly created subscriptionId to your helper-hardhat-config.js.

To deploy the contracts on goerli tesnet

yarn hardhat deploy --network goerli

Once the contracts are deployed on goerli, you need to add them as a consumer to your subscription. You also need to register your contracts to the Chainlink keeper (Don't forget to claim some LINK by using the chainlink faucet).

To update the front end repository with the newly deployed contracts (You need to pull the frontend and set your FRONT_END_FOLDER first)

yarn hardhat deploy --tags frontend

Testing

For unit testing

yarn hardhat test

For integration testing

yarn hardhat test --network goerli