在Binance智能链上,前运行交易机器人(Frontrun Bot)可以通过在交易池中检测价格运动,以在其他人之前完成对指定交易对的交易。以下是一种使用Solidity和Web3.js实现前运行交易机器人的示例代码:
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
contract FrontrunBot is Ownable {
using SafeMath for uint256;
IERC20 public token;
address public flashLoanAddress;
uint256 public minimumProfit; // minimum amount of profit in token decimals, before fees
uint256 private constant FEE_PRECISION = 10000;
uint256 public fee = 300; // 3% fee
uint256 public lastProfit;
event MinimumProfitChanged(uint256 newMinimumProfit);
event FeeChanged(uint256 newFee);
event Profit(uint256 amount);
constructor(address _token, address _flashLoanAddress, uint256 _minimumProfit) {
token = IERC20(_token);
flashLoanAddress = _flashLoanAddress;
minimumProfit = _minimumProfit;
}
function setMinimumProfit(uint256 newMinimumProfit) external onlyOwner {
minimumProfit = newMinimumProfit;
emit MinimumProfitChanged(newMinimumProfit);
}
function setFee(uint256 newFee) external onlyOwner {
fee = newFee;
emit FeeChanged(newFee);
}
function checkProfit(address[] memory trades, uint256[] memory amounts) public view returns(uint256 profit) {
uint256 totalAmount = 0;
for (uint256 i = 0; i < trades.length; i++) {
(bool success, bytes memory data) = trades[i].call{value: 0}(abi.encodeWithSignature("checkTrades(address,uint256)", token, amounts[i]));
require(success, "Call failed");
uint256[] memory prices = abi.decode(data, (uint256[]));