Voting-dApp

The third project from the Alyra formation is to create a voting DApp (Decentralized application).
This project was developed by Adrien Launay & Mickaël Blondeau.

Demo

Video : https://www.loom.com/share/e3147f1fad8c41a9b5a2f92f3861013f
DApp on Vercel : https://alyra-project3-blush.vercel.app/
Voting contract deployed on Goerli in : 0x3c53259ED1ba5490c0380De4f8c66e583E515c89

Requirements

This project uses node and npm. Go check them out if you don't have them locally installed.

It's built from the React Truffle Box.

Recommended versions:

• node: >= v18.16.0
• npm: >= v9.7.1
• ganache: >= 9.7.1

Backend

Install

The backend is built from the react truffle box: use truffle.

$ cd truffle 
$ npm install
$ npx truffle install

Run the tests

$ npm run test

Migrate

Compile and migrate on a local node (ganache):

$ npm run migrate:local

Scripts

Three scripts created to facilitate testing :

• scripts/get_voting_status.js : getting the current status ;
• scripts/register_voters.js : registering 2 voters ;
• scripts/show_accounts.js : show the accounts creatd by ganache ;

$ npm run script:get_voting_status
$ npm run script:register_voters
$ npm run script:show_accounts

Frontend

To run the frontend :

$ cd client
$ npm install
$ npm start

Optimizations from the original Voting contract

startProposalRegistering

Direct struct initialization instead of memory variable:

Cost	Initial Cost	Optimized Cost
gas	109254 gas	109192 gas
transaction cost	95003 gas	94949 gas
execution cost	73939 gas	73885 gas

addProposal

Direct struct initialization instead of memory variable:

Cost	Initial Cost	Optimized Cost
gas	68040 gas	67978 gas
transaction cost	59165 gas	59111 gas
execution cost	37645 gas	37591 gas

setVote

Optimization V1: using a storage variable for voter
Optimization V2: (V1) + using a storage variable for proposal
Optimization V3: (V1, V2) + increment '++var' instead of 'var++'

Cost	Initial Cost	Optimization V1	Optimization V2	Optimization V3
gas	69908 gas	69882 gas	69618 gas	69611 gas
transaction cost	60789 gas	60714 gas	60537 gas	60531 gas
execution cost	39597 gas	39522 gas	39345 gas	39339 gas

Errors

revert could be used with custom errors instead of require and strings.

Fallback function

Default fallback function should be implemented in order to avoid an unwanted payment.

Screenshots