import "@thirdweb-dev/contracts/extension/Permissions.sol";

The Permissions extension provides role-based access control: you can create roles and write custom logic in your smart contract that depends on whether a given wallet holds a given role.

There are two different contracts you can implement to add permissions:

• Permissions: Create roles and restrict access to functions based on those roles.
• PermissionsEnumerable: Permissions plus the capability to view all the addresses holding a specific role (or all roles).

You only need to implement one of the two.

View on GitHub

This is an example smart contract demonstrating how to inherit from this extension and override the functions to add (optional) custom functionality.

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

import "@thirdweb-dev/contracts/extension/Permissions.sol";

contract MyContract is Permissions {
    // Any `bytes32` value is a valid role. You can create roles by defining them like this.
    bytes32 public constant NUMBER_ROLE = keccak256("NUMBER_ROLE");

    // See comments for `setNumber`, below.
    uint256 public number;

    /**
     *  The `Permissions` contract makes an already defined role available: the `DEFAULT_ADMIN_ROLE`.
     *
     *  As an EXAMPLE, we grant the deployer of the contract this admin role.
     */
    constructor() {
        _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
    }

    /**
     *  EXAMPLE: here we have a function that we want to restrict only to holders of `NUMBER_ROLE`.
     *
     *  To accomplish this, we use the `onlyRole` modifier made available by `Permissions`, and
     *  pass it `NUMBER_ROLE` as an argument.
     */
    function setNumber(uint256 _newNumber) public onlyRole(NUMBER_ROLE) {
        number = _newNumber;
    }
}

None of the base contracts implement this extension.