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@maheshmurthy
maheshmurthy / index.js
Created Mar 4, 2019
ethers.js with web3 provider
View index.js
abi = JSON.parse('[{"constant":true,"inputs":[{"name":"candidate","type":"bytes32"}],"name":"totalVotesFor","outputs":[{"name":"","type":"uint8"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"name":"candidate","type":"bytes32"}],"name":"validCandidate","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"name":"","type":"bytes32"}],"name":"votesReceived","outputs":[{"name":"","type":"uint8"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"name":"","type":"uint256"}],"name":"candidateList","outputs":[{"name":"","type":"bytes32"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"name":"candidate","type":"bytes32"}],"name":"voteForCandidate","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"inputs":[{"name":"candidateNames","type":"bytes32[]"}],"payable":false,"stateMutability":"nonpa
@maheshmurthy
maheshmurthy / index.html
Last active Mar 6, 2019
index.html with ethers.js
View index.html
<!DOCTYPE html>
<html>
<head>
<title>Hello World DApp</title>
<link href='https://fonts.googleapis.com/css?family=Open Sans:400,700' rel='stylesheet' type='text/css'>
<link href='https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css' rel='stylesheet' type='text/css'>
</head>
<body class="container">
<h1>A Simple Hello World Voting Application</h1>
<div class="table-responsive">
View MyContract.sol
pragma solidity ^0.4.18;
contract MyContract {
mapping(address => uint) totalTokens;
function buy() payable public {
totalTokens[msg.sender] = msg.value;
}
View hash_migration.js
var Voting = artifacts.require("./Voting.sol");
var ECRecovery = artifacts.require("./ECRecovery.sol");
const sigUtil = require("eth-sig-util")
var alice_vote_hash = sigUtil.typedSignatureHash([{ type: 'string', name: 'Message', value: "Vote for Alice"}])
var bob_vote_hash = sigUtil.typedSignatureHash([{ type: 'string', name: 'Message', value: "Vote for Bob"}])
var carol_vote_hash = sigUtil.typedSignatureHash([{ type: 'string', name: 'Message', value: "Vote for Carol"}])
module.exports = function(deployer) {
View Voting.sol
pragma solidity ^0.4.18;
import "./ECRecovery.sol";
contract Voting {
using ECRecovery for bytes32;
mapping (bytes32 => uint8) public votesReceived;
mapping(bytes32 => bytes32) public candidateHash;
View submit_vote.js
window.submitVote = function(candidate) {
let candidateName = $("#candidate-name").val();
let signature = $("#vote-signature").val();
let voterAddress = $("#voter-address").val();
$("#msg").html("Vote has been submitted. The vote count will increment as soon as the vote is recorded on the blockchain. Please wait.")
Voting.deployed().then(function(contractInstance) {
contractInstance.voteForCandidate(candidateName, voterAddress, signature, {gas: 140000, from: web3.eth.accounts[0]}).then(function() {
@maheshmurthy
maheshmurthy / sign_vote.js
Last active Apr 15, 2018
Ethereum Voting Dapp sign and verify
View sign_vote.js
window.voteForCandidate = function(candidate) {
let candidateName = $("#candidate").val();
let msgParams = [
{
type: 'string', // Any valid solidity type
name: 'Message', // Any string label you want
value: 'Vote for ' + candidateName // The value to sign
}
]
View meetup notes
web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"))
View contract-variables.js
// We use the struct datatype to store the voter information.
struct voter {
address voterAddress; // The address of the voter
uint tokensBought; // The total no. of tokens this voter owns
uint[] tokensUsedPerCandidate; // Array to keep track of votes per candidate.
/* We have an array called candidateList initialized below.
Every time this voter votes with her tokens, the value at that
index is incremented. Example, if candidateList array declared
below has ["Rama", "Nick", "Jose"] and this
voter votes 10 tokens to Nick, the tokensUsedPerCandidate[1]
View index.html
<!DOCTYPE html>
<html>
<head>
<title>Hello World DApp</title>
<link href='https://fonts.googleapis.com/css?family=Open Sans:400,700' rel='stylesheet' type='text/css'>
<link href='https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css' rel='stylesheet' type='text/css'>
</head>
<body class="container">
<h1>A Simple Hello World Voting Application</h1>
<div class="table-responsive">