The original voting demo used web3 1.0.0-beta.33 and Solidity 0.4.21. It considered three placements for signing and event delivery:
| Arrangement | Where signing happens | Important boundary |
|---|---|---|
| Server-centered | Backend holds signing material | Server custody and request authorization |
| Browser-centered | Wallet provider signs in the browser | User approval and provider behavior |
| Split UI/backend | Browser signs; backend listens and relays | Event identity, confirmation, and relay state |
The original third arrangement did not implement its Socket.IO relay. The older provider-subscription limitation was an observation from that toolchain, not a current wallet capability claim.
The historical contract
pragma solidity 0.4.21;
contract Voting {
// @nhancv: Define candidate
struct Candidate {
uint8 id;
string name;
uint8 point;
}
// @nhancv: Candidate list
Candidate[] public candidateList;
// @nhancv: Event
event AddCandidateEvent(address indexed from, uint8 candidateId);
event VoteCandidateEvent(address indexed from, uint8 candidateId);
// @nhancv: Get length of Candidate list
function getNumberCandidate() public view returns (uint8) {
return uint8(candidateList.length);
}
// @nhancv: Addition candidate
function addCandidate(string name) public {
Candidate memory candidate = Candidate(uint8(candidateList.length + 1), name, 0);
candidateList.push(candidate);
emit AddCandidateEvent(msg.sender, candidate.id);
}
// @nhancv: Get winner
function getWinner() public view returns (uint8 candidateId) {
Candidate memory candidate;
for (uint i = 0; i < candidateList.length; i++) {
if (candidate.point < candidateList[i].point) {
candidate = candidateList[i];
}
}
return candidate.id;
}
// @nhancv: Vote for candidate
function voteCandidate(uint8 candidateId) public payable returns (uint8) {
for (uint i = 0; i < candidateList.length; i++) {
if (candidateList[i].id == candidateId) {
candidateList[i].point++;
emit VoteCandidateEvent(msg.sender, candidateId);
return candidateList[i].point;
}
}
return 0;
}
}A small payable voting demo is not an election system. Voter eligibility, repeat voting, candidate access control, arithmetic width, ties, and event/finality handling need explicit rules beyond this listing.
Source: Gist revision and earlier demo repository. No contract was deployed, payment sent, or vote cast.