Truffle Quick Start Guide
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Wrapping up

Your final TaskMaster.sol file should look like this:

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
isOwner()
hasSufficientFunds(rewardAmount)
returns(bool sufficientFunds)
{
balances[msg.sender] -= rewardAmount;
balances[doer] += rewardAmount;
return sufficientFunds;
}

function getBalance(address addr) public view returns(uint) {
return balances[addr];
}

modifier isOwner() {
require(msg.sender == owner);
_;
}

modifier hasSufficientFunds(uint rewardAmount) {
require(balances[msg.sender] >= rewardAmount);
_;
}
}

You can also find this file in the repo, under contracts (https://github.com/PacktPublishing/Truffle-Quick-Start-Guide/blob/master/chapter1/contracts/TaskMaster.sol).

Now that we've created a full TaskMaster.sol file, you can do the following bit of housekeeping.

Delete all contents of migrations/2_deploy_contracts.js and replace them with the following code:

var TaskMaster = artifacts.require("./TaskMaster.sol");

module.exports = function(deployer) {
deployer.deploy(TaskMaster);
};

This specifies that TaskMaster.sol should be deployed to a blockchain. You will learn more about migrations in Chapter 4, Migrating Your Dapp to Ethereum Blockchains.