Fetch election calls with Solidity

If you want to connect to the AP Election results in Solidity and deploy an Ethereum smart contract, learn how here.

🚀 Want a shortcut? 🚀

Start with our boilerplate Solidity smart contract on GitHub.

Walkthrough

  1. Begin by starting a Truffle project or using Remix

  2. Set pragma and import the election results contract at the top of your smart contract

pragma solidity ^0.6.12;

import "https://raw.githubusercontent.com/EveripediaNetwork/everipedia-ap-2020/master/ethereum/contracts/TestnetConsumer.sol";

3. Paste in this example code and change the selectWinner function to do what you need with the data!

contract FetchPresidentialWinners {
    struct Winner {
      string winner;
      uint256 resultNow;
      uint256 resultBlock;
    }
    
    ATestnetConsumer internal winners;
    
    constructor() public {
        // the deployed kovan test contract address
        winners = ATestnetConsumer(0x12B7B8Dea45AF31b6303E00C735332A8b6752856);
        
        // the deployed mainnet contract address
        // winners = ATestnetConsumer(0x0792724900B551d200D954a5Ed709d9514d73A9F);
    }
    
    
   function selectWinner(string memory _state) public view returns (string memory winner, uint256 resultNow, uint256 resultBlock)
  {
    (string memory winner, uint256 resultNow, uint256 resultBlock) = winners.presidentialWinners(_state);
    return (winner, resultNow, resultBlock);
  }
}

4. Validate on kovan that you are getting what you expect from the presidentialWinners mapping.

If you're using the above solidity code, you can see here the "already declared states" (all Kovan test data)

5. Fetch state data for any of all the states you are interested (52 states = 50 + D.C. + US). See the exact list of states here.

6. Still having issues?

  1. Learn more about Chainlink Oracles at https://docs.chain.link/docs

  2. Tweet to @dawsonbotsford and @everipedia any engineering questions (or send a DM on Twitter to @dawsonbotsford)

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