Metamask: How to create smart contract using openzeppelin metatx relayer to receive and withdraw usdt erc20 token using metamask?

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 a MetaMask account.

Creating a Smart Contract with OpenZeppelin Defender Relay

To use the OpenZeppelin Defender relay, we’ll need to create a new smart contract that can handle gasless transactions. Here’s an example of how you can achieve this:

First, let’s create a new smart contract in Solidity that will be used as the relayer for our MetaMask wallet. We’ll call it RelayContract.

pragma solidity ^0.8.0;


import "

import "


contract RelayContract {

    // Mapping of address to their balances

    mapping(address => uint256) public balances;


    function withdrawToken(uint256 _amount, address _recipient) public {

        require(balances[msg.sender] >= _amount, "Insufficient balance");

        require(_amount <= 10**18, "Invalid amount");


        // Use OpenZeppelin Defender to handle gasless transactions

        bytes memory data = abi.encodeWithSignature("withdrawToken", _amount, msg.sender);


        // Call the relay contract with the 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 set up OpenZeppelin Defender to handle gasless transactions.

pragma solidity ^0.8.0;


import "

import "


contract MetaMaskWallet {

    // Mapping of address to their balances

    mapping(address => uint256) public balances;


    // Function to add a new account to the wallet

    function addAccount(address _newAddress, uint256 _amount) public {

        balances[_newAddress] = _amount;

    }


    // Function to remove an account from the wallet

    function removeAccount(address _address) public {

        balances[_address] = 0;

    }

}

Connect our MetaMask wallet to OpenZeppelin Defender.

pragma solidity ^0.8.0;


import "

import "


contract Defender {

    // Mapping of address to their balances

    mapping(address => uint256) public balances;


    function addAccount(address _newAddress, uint256 _amount) internal {

        balances[_newAddress] = _amount;

    }


    function removeAccount(address _address) internal {

        balances[_address] = 0;

    }

}

Next, let’s create a MetaMask wallet that uses this new smart contract.

“`solidity

pragma solidity ^0.8.0;

import “

import “

import “