openzeppelin-contracts/contracts/examples/SampleCrowdsale.sol

pragma solidity ^0.4.24;

import "../crowdsale/validation/CappedCrowdsale.sol";
import "../crowdsale/distribution/RefundableCrowdsale.sol";
import "../crowdsale/emission/MintedCrowdsale.sol";
import "../token/ERC20/ERC20Mintable.sol";

/**
 * @title SampleCrowdsaleToken
 * @dev Very simple ERC20 Token that can be minted.
 * It is meant to be used in a crowdsale contract.
 */
contract SampleCrowdsaleToken is ERC20Mintable {

  string public constant name = "Sample Crowdsale Token";
  string public constant symbol = "SCT";
  uint8 public constant decimals = 18;
}

/**
 * @title SampleCrowdsale
 * @dev This is an example of a fully fledged crowdsale.
 * The way to add new features to a base crowdsale is by multiple inheritance.
 * In this example we are providing following extensions:
 * CappedCrowdsale - sets a max boundary for raised funds
 * RefundableCrowdsale - set a min goal to be reached and returns funds if it's not met
 *
 * After adding multiple features it's good practice to run integration tests
 * to ensure that subcontracts works together as intended.
 */
// XXX There doesn't seem to be a way to split this line that keeps solium
// happy. See:
// https://github.com/duaraghav8/Solium/issues/205
// --elopio - 2018-05-10
// solium-disable-next-line max-len
contract SampleCrowdsale is CappedCrowdsale, RefundableCrowdsale, MintedCrowdsale {

  constructor(
    uint256 openingTime,
    uint256 closingTime,
    uint256 rate,
    address wallet,
    uint256 cap,
    ERC20Mintable token,
    uint256 goal
  )
    public
    Crowdsale(rate, wallet, token)
    CappedCrowdsale(cap)
    TimedCrowdsale(openingTime, closingTime)
    RefundableCrowdsale(goal)
  {
    //As goal needs to be met for a successful crowdsale
    //the value needs to less or equal than a cap which is limit for accepted funds
    require(goal <= cap);
  }
}