CreateAccount.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
declare(strict_types=1);

namespace Magento\CustomerGraphQl\Model\Customer;

use Magento\Customer\Api\AccountManagementInterface;
use Magento\Customer\Api\Data\CustomerInterface;
use Magento\Customer\Api\Data\CustomerInterfaceFactory;
use Magento\Framework\Api\DataObjectHelper;
use Magento\Framework\Exception\LocalizedException;
use Magento\Framework\Exception\NoSuchEntityException;
use Magento\Store\Model\StoreManagerInterface;

/**
 * Class CreateAccount creates new customer account
 */
class CreateAccount
{
    /**
     * @var DataObjectHelper
     */
    private $dataObjectHelper;

    /**
     * @var CustomerInterfaceFactory
     */
    private $customerFactory;

    /**
     * @var AccountManagementInterface
     */
    private $accountManagement;

    /**
     * @var StoreManagerInterface
     */
    private $storeManager;

    /**
     * @param DataObjectHelper $dataObjectHelper
     * @param CustomerInterfaceFactory $customerFactory
     * @param StoreManagerInterface $storeManager
     * @param AccountManagementInterface $accountManagement
     */
    public function __construct(
        DataObjectHelper $dataObjectHelper,
        CustomerInterfaceFactory $customerFactory,
        StoreManagerInterface $storeManager,
        AccountManagementInterface $accountManagement
    ) {
        $this->dataObjectHelper = $dataObjectHelper;
        $this->customerFactory = $customerFactory;
        $this->accountManagement = $accountManagement;
        $this->storeManager = $storeManager;
    }

    /**
     * Creates new customer account
     *
     * @param array $args
     * @return CustomerInterface
     * @throws LocalizedException
     * @throws NoSuchEntityException
     */
    public function execute(array $args): CustomerInterface
    {
        $customerDataObject = $this->customerFactory->create();
        $this->dataObjectHelper->populateWithArray(
            $customerDataObject,
            $args['input'],
            CustomerInterface::class
        );
        $store = $this->storeManager->getStore();
        $customerDataObject->setWebsiteId($store->getWebsiteId());
        $customerDataObject->setStoreId($store->getId());

        $password = array_key_exists('password', $args['input']) ? $args['input']['password'] : null;

        return $this->accountManagement->createAccount($customerDataObject, $password);
    }
}