<form method="POST">
    <h3>Editing: CartUpdateCustomer.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
namespace Automattic\WooCommerce\StoreApi\Routes\V1;

use Automattic\WooCommerce\StoreApi\Utilities\DraftOrderTrait;

/**
 * CartUpdateCustomer class.
 *
 * Updates the customer billing and shipping addresses, recalculates the cart totals, and returns an updated cart.
 */
class CartUpdateCustomer extends AbstractCartRoute {
	use DraftOrderTrait;

	/**
	 * The route identifier.
	 *
	 * @var string
	 */
	const IDENTIFIER = 'cart-update-customer';

	/**
	 * Get the path of this REST route.
	 *
	 * @return string
	 */
	public function get_path() {
		return self::get_path_regex();
	}

	/**
	 * Get the path of this rest route.
	 *
	 * @return string
	 */
	public static function get_path_regex() {
		return '/cart/update-customer';
	}

	/**
	 * Get method arguments for this REST route.
	 *
	 * @return array An array of endpoints.
	 */
	public function get_args() {
		return [
			[
				'methods'             =&gt; \WP_REST_Server::CREATABLE,
				'callback'            =&gt; [ $this, 'get_response' ],
				'permission_callback' =&gt; '__return_true',
				'args'                =&gt; [
					'billing_address'  =&gt; [
						'description'       =&gt; __( 'Billing address.', 'woocommerce' ),
						'type'              =&gt; 'object',
						'context'           =&gt; [ 'view', 'edit' ],
						'properties'        =&gt; $this-&gt;schema-&gt;billing_address_schema-&gt;get_properties(),
						'sanitize_callback' =&gt; null,
					],
					'shipping_address' =&gt; [
						'description'       =&gt; __( 'Shipping address.', 'woocommerce' ),
						'type'              =&gt; 'object',
						'context'           =&gt; [ 'view', 'edit' ],
						'properties'        =&gt; $this-&gt;schema-&gt;shipping_address_schema-&gt;get_properties(),
						'sanitize_callback' =&gt; null,
					],
				],
			],
			'schema'      =&gt; [ $this-&gt;schema, 'get_public_item_schema' ],
			'allow_batch' =&gt; [ 'v1' =&gt; true ],
		];
	}

	/**
	 * Validate address params now they are populated.
	 *
	 * @param \WP_REST_Request $request Request object.
	 * @param array            $billing Billing address.
	 * @param array            $shipping Shipping address.
	 * @return \WP_Error|true
	 */
	protected function validate_address_params( $request, $billing, $shipping ) {
		$posted_billing  = isset( $request['billing_address'] );
		$posted_shipping = isset( $request['shipping_address'] );
		$invalid_params  = array();
		$invalid_details = array();

		if ( $posted_billing ) {
			$billing_validation_check = $this-&gt;schema-&gt;billing_address_schema-&gt;validate_callback( $billing, $request, 'billing_address' );

			if ( false === $billing_validation_check ) {
				$invalid_params['billing_address'] = __( 'Invalid parameter.', 'woocommerce' );
			} elseif ( is_wp_error( $billing_validation_check ) ) {
				$invalid_params['billing_address']  = implode( ' ', $billing_validation_check-&gt;get_error_messages() );
				$invalid_details['billing_address'] = \rest_convert_error_to_response( $billing_validation_check )-&gt;get_data();
			}
		}

		if ( $posted_shipping ) {
			$shipping_validation_check = $this-&gt;schema-&gt;shipping_address_schema-&gt;validate_callback( $shipping, $request, 'shipping_address' );

			if ( false === $shipping_validation_check ) {
				$invalid_params['shipping_address'] = __( 'Invalid parameter.', 'woocommerce' );
			} elseif ( is_wp_error( $shipping_validation_check ) ) {
				$invalid_params['shipping_address']  = implode( ' ', $shipping_validation_check-&gt;get_error_messages() );
				$invalid_details['shipping_address'] = \rest_convert_error_to_response( $shipping_validation_check )-&gt;get_data();
			}
		}

		if ( $invalid_params ) {
			return new \WP_Error(
				'rest_invalid_param',
				/* translators: %s: List of invalid parameters. */
				sprintf( __( 'Invalid parameter(s): %s', 'woocommerce' ), implode( ', ', array_keys( $invalid_params ) ) ),
				[
					'status'  =&gt; 400,
					'params'  =&gt; $invalid_params,
					'details' =&gt; $invalid_details,
				]
			);
		}

		return true;
	}

	/**
	 * Handle the request and return a valid response for this endpoint.
	 *
	 * @param \WP_REST_Request $request Request object.
	 * @return \WP_REST_Response
	 */
	protected function get_route_post_response( \WP_REST_Request $request ) {
		$cart     = $this-&gt;cart_controller-&gt;get_cart_instance();
		$customer = wc()-&gt;customer;

		// Get data from request object and merge with customer object, then sanitize.
		$billing  = $this-&gt;schema-&gt;billing_address_schema-&gt;sanitize_callback(
			wp_parse_args(
				$request['billing_address'] ?? [],
				$this-&gt;get_customer_billing_address( $customer )
			),
			$request,
			'billing_address'
		);
		$shipping = $this-&gt;schema-&gt;billing_address_schema-&gt;sanitize_callback(
			wp_parse_args(
				$request['shipping_address'] ?? [],
				$this-&gt;get_customer_shipping_address( $customer )
			),
			$request,
			'shipping_address'
		);

		// If the cart does not need shipping, shipping address is forced to match billing address unless defined.
		if ( ! $cart-&gt;needs_shipping() &amp;&amp; ! isset( $request['shipping_address'] ) ) {
			$shipping = $billing;
		}

		// Run validation and sanitization now that the cart and customer data is loaded.
		$billing  = $this-&gt;schema-&gt;billing_address_schema-&gt;sanitize_callback( $billing, $request, 'billing_address' );
		$shipping = $this-&gt;schema-&gt;shipping_address_schema-&gt;sanitize_callback( $shipping, $request, 'shipping_address' );

		// Validate data now everything is clean..
		$validation_check = $this-&gt;validate_address_params( $request, $billing, $shipping );

		if ( is_wp_error( $validation_check ) ) {
			return rest_ensure_response( $validation_check );
		}

		$customer-&gt;set_props(
			array(
				'billing_first_name'  =&gt; $billing['first_name'] ?? null,
				'billing_last_name'   =&gt; $billing['last_name'] ?? null,
				'billing_company'     =&gt; $billing['company'] ?? null,
				'billing_address_1'   =&gt; $billing['address_1'] ?? null,
				'billing_address_2'   =&gt; $billing['address_2'] ?? null,
				'billing_city'        =&gt; $billing['city'] ?? null,
				'billing_state'       =&gt; $billing['state'] ?? null,
				'billing_postcode'    =&gt; $billing['postcode'] ?? null,
				'billing_country'     =&gt; $billing['country'] ?? null,
				'billing_phone'       =&gt; $billing['phone'] ?? null,
				'billing_email'       =&gt; $billing['email'] ?? null,
				'shipping_first_name' =&gt; $shipping['first_name'] ?? null,
				'shipping_last_name'  =&gt; $shipping['last_name'] ?? null,
				'shipping_company'    =&gt; $shipping['company'] ?? null,
				'shipping_address_1'  =&gt; $shipping['address_1'] ?? null,
				'shipping_address_2'  =&gt; $shipping['address_2'] ?? null,
				'shipping_city'       =&gt; $shipping['city'] ?? null,
				'shipping_state'      =&gt; $shipping['state'] ?? null,
				'shipping_postcode'   =&gt; $shipping['postcode'] ?? null,
				'shipping_country'    =&gt; $shipping['country'] ?? null,
				'shipping_phone'      =&gt; $shipping['phone'] ?? null,
			)
		);
		// We want to only get additional fields passed, since core ones are already saved.
		$core_fields = array_keys( $this-&gt;additional_fields_controller-&gt;get_core_fields() );

		$additional_shipping_values = array_diff_key( $shipping, array_flip( $core_fields ) );
		$additional_billing_values  = array_diff_key( $billing, array_flip( $core_fields ) );

		// We save them one by one, and we add the group prefix.
		foreach ( $additional_shipping_values as $key =&gt; $value ) {
			$this-&gt;additional_fields_controller-&gt;persist_field_for_customer( $key, $value, $customer, 'shipping' );
		}
		foreach ( $additional_billing_values as $key =&gt; $value ) {
			$this-&gt;additional_fields_controller-&gt;persist_field_for_customer( $key, $value, $customer, 'billing' );
		}

		wc_do_deprecated_action(
			'woocommerce_blocks_cart_update_customer_from_request',
			array(
				$customer,
				$request,
			),
			'7.2.0',
			'woocommerce_store_api_cart_update_customer_from_request',
			'This action was deprecated in WooCommerce Blocks version 7.2.0. Please use woocommerce_store_api_cart_update_customer_from_request instead.'
		);

		/**
		 * Fires when the Checkout Block/Store API updates a customer from the API request data.
		 *
		 * @since 7.2.0
		 *
		 * @param \WC_Customer $customer Customer object.
		 * @param \WP_REST_Request $request Full details about the request.
		 */
		do_action( 'woocommerce_store_api_cart_update_customer_from_request', $customer, $request );

		$customer-&gt;save();

		$this-&gt;cart_controller-&gt;calculate_totals();

		return rest_ensure_response( $this-&gt;schema-&gt;get_item_response( $cart ) );
	}

	/**
	 * Get full customer billing address.
	 *
	 * @param \WC_Customer $customer Customer object.
	 * @return array
	 */
	protected function get_customer_billing_address( \WC_Customer $customer ) {
		$additional_fields = $this-&gt;additional_fields_controller-&gt;get_all_fields_from_object( $customer, 'billing' );

		return array_merge(
			[
				'first_name' =&gt; $customer-&gt;get_billing_first_name(),
				'last_name'  =&gt; $customer-&gt;get_billing_last_name(),
				'company'    =&gt; $customer-&gt;get_billing_company(),
				'address_1'  =&gt; $customer-&gt;get_billing_address_1(),
				'address_2'  =&gt; $customer-&gt;get_billing_address_2(),
				'city'       =&gt; $customer-&gt;get_billing_city(),
				'state'      =&gt; $customer-&gt;get_billing_state(),
				'postcode'   =&gt; $customer-&gt;get_billing_postcode(),
				'country'    =&gt; $customer-&gt;get_billing_country(),
				'phone'      =&gt; $customer-&gt;get_billing_phone(),
				'email'      =&gt; $customer-&gt;get_billing_email(),
			],
			$additional_fields
		);
	}

	/**
	 * Get full customer shipping address.
	 *
	 * @param \WC_Customer $customer Customer object.
	 * @return array
	 */
	protected function get_customer_shipping_address( \WC_Customer $customer ) {
		$additional_fields = $this-&gt;additional_fields_controller-&gt;get_all_fields_from_object( $customer, 'shipping' );

		return array_merge(
			[
				'first_name' =&gt; $customer-&gt;get_shipping_first_name(),
				'last_name'  =&gt; $customer-&gt;get_shipping_last_name(),
				'company'    =&gt; $customer-&gt;get_shipping_company(),
				'address_1'  =&gt; $customer-&gt;get_shipping_address_1(),
				'address_2'  =&gt; $customer-&gt;get_shipping_address_2(),
				'city'       =&gt; $customer-&gt;get_shipping_city(),
				'state'      =&gt; $customer-&gt;get_shipping_state(),
				'postcode'   =&gt; $customer-&gt;get_shipping_postcode(),
				'country'    =&gt; $customer-&gt;get_shipping_country(),
				'phone'      =&gt; $customer-&gt;get_shipping_phone(),
			],
			$additional_fields
		);
	}
}
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