Creating a reward method

This will be invoked by the owner to reward a doer for their successful completion of a task:

pragma solidity ^0.4.17;


contract TaskMaster {
    mapping (address => uint) public balances; // balances of everyone
    address public owner; // owner of the contract

    function TaskMaster() public {
        owner = msg.sender;        
        balances[msg.sender] = 10000;
    }

    function reward(address doer, uint rewardAmount)
        public
        returns(bool sufficientFunds)
    {
        balances[msg.sender] -= rewardAmount;
        balances[doer] += rewardAmount;
        return sufficientFunds;
    }
}

This function accepts the following:

• an address for the doer
• an integer amount for their reward

We are almost there—we need to add some necessary security touches.

Notice how we are not performing a real transfer of ETH, but rather we simply decrement the balance of the owner and increment the balance of the doer. The reason we don't perform a real transfer here is because we simply hard-coded a balance value of 10000 and made up a token called TodoCoin. Remember, our goal in this chapter is to get a fully functioning Dapp using Truffle.