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ERC20 Signature Mint

import "@thirdweb-dev/contracts/base/ERC20SignatureMint.sol";

The ERC20SignatureMint smart contract adds the signature-based minting extension functionality to the ERC20Base contract.

Signature minting uses EIP-712, which enables the contract admin to authorize an external party's request to mint tokens on the admin's contract. At a high level, this means you can authorize others to mint tokens on your contract, and specify what exactly will be minted by that external party.

Detected Extensions​

Once deployed, you can use the features made available by these extensions on the SDK and dashboard:

Click on each feature to learn more about what functions are available.

Usage​

Import the contract and inherit from it.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@thirdweb-dev/contracts/base/ERC20SignatureMint.sol";

contract MyToken is ERC20SignatureMint {
      constructor(
        address _defaultAdmin,
        string memory _name,
        string memory _symbol,
        address _primarySaleRecipient
    )
        ERC20SignatureMint(
            _defaultAdmin,
            _name,
            _symbol,
            _primarySaleRecipient
        )
    {}
}

Functions to Override​

The following functions have been implemented on this contract & are available to be overridden to add custom logic:

mintWithSignature
    /**
     *  @notice           Mints tokens according to the provided mint request.
     *
     *  @param _req       The payload / mint request.
     *  @param _signature The signature produced by an account signing the mint request.
     */
    function mintWithSignature(MintRequest calldata _req, bytes calldata _signature)
        external
        payable
        virtual
        returns (address signer)
    {
        require(_req.quantity > 0, "Minting zero tokens.");

        // Verify and process payload.
        signer = _processRequest(_req, _signature);

        address receiver = _req.to;

        // Collect price
        _collectPriceOnClaim(_req.primarySaleRecipient, _req.quantity, _req.currency, _req.pricePerToken);

        // Mint tokens.
        _mint(receiver, _req.quantity);

        emit TokensMintedWithSignature(signer, receiver, _req);
    }
_collectPriceOnClaim
     /// @dev Collects and distributes the primary sale value of tokens being claimed.
    function _collectPriceOnClaim(
        address _primarySaleRecipient,
        uint256 _quantityToClaim,
        address _currency,
        uint256 _pricePerToken
    ) internal virtual {
        if (_pricePerToken == 0) {
            return;
        }

        uint256 totalPrice = (_quantityToClaim * _pricePerToken) / 1 ether;
        require(totalPrice > 0, "quantity too low");

        if (_currency == CurrencyTransferLib.NATIVE_TOKEN) {
            require(msg.value == totalPrice, "Must send total price.");
        }

        address saleRecipient = _primarySaleRecipient == address(0) ? primarySaleRecipient() : _primarySaleRecipient;
        CurrencyTransferLib.transferCurrency(_currency, msg.sender, saleRecipient, totalPrice);
    }