aave-protocol-v2/contracts/interfaces/IExchangeAdapter.sol

// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.6.8;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

interface IExchangeAdapter {
    event Exchange(
        address indexed from,
        address indexed to,
        address indexed platform,
        uint256 fromAmount,
        uint256 toAmount
    );

    function approveExchange(IERC20[] calldata _tokens) external;

    function exchange(address _from, address _to, uint256 _amount, uint256 _maxSlippage) external returns(uint256);
}