FundMe.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";

contract FundMe {

    mapping(address => uint256) public addressToAmountFunded;
    address[] public funders;
    address public owner;

    constructor() {
        owner = msg.sender;
    }

    function fund() public payable {
        uint256 minimumUSD = 50 * 10 ** 18;
        require(getConversionRate(msg.value) >= minimumUSD, "You need to spend more ETH!");
        addressToAmountFunded[msg.sender] += msg.value;
        funders.push(msg.sender);
    }

    function getVersion() public view returns (uint256){
        AggregatorV3Interface priceFeed = AggregatorV3Interface(0x8A753747A1Fa494EC906cE90E9f37563A8AF630e);
        
        return priceFeed.version();
    }

    function getPrice() public view returns(uint256){
        AggregatorV3Interface priceFeed = AggregatorV3Interface(0x8A753747A1Fa494EC906cE90E9f37563A8AF630e);
        (,int256 answer,,,) = priceFeed.latestRoundData();

        return uint256(answer * 10000000000);
    }

    function getConversionRate(uint256 ethAmount) public view returns (uint256){
        uint256 ethPrice = getPrice();
        uint256 ethAmountInUsd = (ethPrice * ethAmount) / (10**18);
        return ethAmountInUsd;
    }

    modifier onlyOwner {
        require(msg.sender == owner, "You're not the owner of this contract!");
        _;
    }

    function withdraw() payable onlyOwner public {
        payable(msg.sender).transfer(address(this).balance);
        for (uint256 funderIdx=0; funderIdx < funders.length; funderIdx++) {
            address funder = funders[funderIdx];
            addressToAmountFunded[funder] = 0;
        }

        funders = new address[](0);
    }
}