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@maheshmurthy

maheshmurthy/index.js

Last active Mar 24, 2020
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import Web3 from "web3";
import votingArtifact from "../../build/contracts/Voting.json";
let candidates = {"Rama": "candidate-1", "Nick": "candidate-2", "Jose": "candidate-3"}
const App = {
web3: null,
account: null,
voting: null,
start: async function() {
const { web3 } = this;
try {
/* Get the network we are connected to and then read the build/contracts/Voting.json and instantiate a contract object to use
*/
//
const networkId = await web3.eth.net.getId();
const deployedNetwork = votingArtifact.networks[networkId];
this.voting = new web3.eth.Contract(
votingArtifact.abi,
deployedNetwork.address,
);
// get accounts
const accounts = await web3.eth.getAccounts();
this.account = accounts[0];
this.loadCandidatesAndVotes();
} catch (error) {
console.error("Could not connect to contract or chain.");
}
},
loadCandidatesAndVotes: async function() {
const { totalVotesFor } = this.voting.methods;
//const { sendCoin } = this.meta.methods;
//await sendCoin(receiver, amount).send({ from: this.account });
let candidateNames = Object.keys(candidates);
for (var i = 0; i < candidateNames.length; i++) {
let name = candidateNames[i];
var count = await totalVotesFor(this.web3.utils.asciiToHex(name)).call();
$("#" + candidates[name]).html(count);
}
},
voteForCandidate: async function() {
let candidateName = $("#candidate").val();
$("#msg").html("Vote has been submitted. The vote count will increment as soon as the vote is recorded on the blockchain. Please wait.")
$("#candidate").val("");
const { totalVotesFor, voteForCandidate } = this.voting.methods;
/* Voting.deployed() returns an instance of the contract. Every call
* in Truffle returns a promise which is why we have used then()
* everywhere we have a transaction call
*/
await voteForCandidate(this.web3.utils.asciiToHex(candidateName)).send({gas: 140000, from: this.account});
let div_id = candidates[candidateName];
var count = await totalVotesFor(this.web3.utils.asciiToHex(candidateName)).call();
$("#" + div_id).html(count);
$("#msg").html("");
}
};
window.App = App;
window.addEventListener("load", function() {
if (window.ethereum) {
// use MetaMask's provider
App.web3 = new Web3(window.ethereum);
window.ethereum.enable(); // get permission to access accounts
} else {
console.warn(
"No web3 detected. Falling back to http://127.0.0.1:8545. You should remove this fallback when you deploy live",
);
// fallback - use your fallback strategy (local node / hosted node + in-dapp id mgmt / fail)
App.web3 = new Web3(
new Web3.providers.HttpProvider("http://127.0.0.1:8545"),
);
}
App.start();
});
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