I can provide you with an article on how to create a Metamask wallet that uses the OpenZeppelin Defender relay contract to receive and withdraw USD tokens (ERC-20) using your MetaMask account.
Creating a Smart Contract with OpenZeppelin Defender Relay
To use the OpenZeppelin Defender relay, we need to create a new smart contract that can handle gas-free transactions. Here is an example of how you can achieve this:
First, let’s create a new smart contract in Solidity that will be used as a relay for our MetaMask wallet. Let’s call it RelayContract.
pragma solidity ^0.8.0;
import "
import "
contract RelayContract {
// Mapping addresses to their balances
mapping (address => uint256) public balance;
function withdrawToken(uint256 _amount, address _recipient) public {
require(balances[msg.sender] >= _amount, "Insufficient balance");
require(_amount <= 10**18, "Invalid amount");
// Use OpenZeppelin Defender to process gasless transactions
bytes memory data = abi.encodeWithSignature("withdrawToken", _amount, msg.sender);
// Calling the relay contract with data as a function call
(bool success, ) = openzeppelinDefender.relay(data);
}
}
Next, let’s create a MetaMask wallet that can use this new smart contract. We’ll also configure OpenZeppelin Defender to support gasless transactions.
pragma solidity ^0.8.0;
import "
import "
contract MetaMaskWallet {
// Mapping addresses to their states
mapping ( address => uint256 ) public balance ;
// Function to add a new account to the wallet
function addAccount(address _newAdresa, uint256 _amount) public {
state[_newAdresa] = _amount;
}
// Function to remove account from wallet
function removeAccount(address _address) public {
state[_address] = 0;
}
}
Now let’s connect our MetaMask wallet to OpenZeppelin Defender.
pragma solidity ^0.8.0;
import "
import "
contract Defender {
// Mapping addresses to their balances
mapping (address => uint256) public balance;
function addAccount(address _newAddress, uint256 _amount) internal {
balance[_newAddress] = _amount;
}
function removeAccount(address _address) internal {
balance[_address] = 0;
}
}
Next, let’s create a MetaMask wallet that uses this new smart contract.
“`solidity
pragma solidity ^0.8.0;
import “
import “
import “
