wp_validate_site_data( WP_Error $errors, array $data, WP_Site|null $old_site = null )

575function wp_validate_site_data( $errors, $data, $old_site = null ) {576	// A domain must always be present.577	if ( empty( $data['domain'] ) ) {578		$errors->add( 'site_empty_domain', __( 'Site domain must not be empty.' ) );579	}580 581	// A path must always be present.582	if ( empty( $data['path'] ) ) {583		$errors->add( 'site_empty_path', __( 'Site path must not be empty.' ) );584	}585 586	// A network ID must always be present.587	if ( empty( $data['network_id'] ) ) {588		$errors->add( 'site_empty_network_id', __( 'Site network ID must be provided.' ) );589	}590 591	// Both registration and last updated dates must always be present and valid.592	$date_fields = array( 'registered', 'last_updated' );593	foreach ( $date_fields as $date_field ) {594		if ( empty( $data[ $date_field ] ) ) {595			$errors->add( 'site_empty_' . $date_field, __( 'Both registration and last updated dates must be provided.' ) );596			break;597		}598 599		// Allow '0000-00-00 00:00:00', although it be stripped out at this point.600		if ( '0000-00-00 00:00:00' !== $data[ $date_field ] ) {601			$month      = substr( $data[ $date_field ], 5, 2 );602			$day        = substr( $data[ $date_field ], 8, 2 );603			$year       = substr( $data[ $date_field ], 0, 4 );604			$valid_date = wp_checkdate( $month, $day, $year, $data[ $date_field ] );605			if ( ! $valid_date ) {606				$errors->add( 'site_invalid_' . $date_field, __( 'Both registration and last updated dates must be valid dates.' ) );607				break;608			}609		}610	}611 612	if ( ! empty( $errors->errors ) ) {613		return;614	}615 616	// If a new site, or domain/path/network ID have changed, ensure uniqueness.617	if ( ! $old_site618		|| $data['domain'] !== $old_site->domain619		|| $data['path'] !== $old_site->path620		|| $data['network_id'] !== $old_site->network_id621	) {622		if ( domain_exists( $data['domain'], $data['path'], $data['network_id'] ) ) {623			$errors->add( 'site_taken', __( 'Sorry, that site already exists!' ) );624		}625	}626}