WP_REST_Meta_Fields::prepare_value() WordPress Method

	public static function prepare_value( $value, $request, $args ) {
		if ( $args['single'] ) {
			$schema = $args['schema'];
		} else {
			$schema = $args['schema']['items'];
		}

		if ( '' === $value && in_array( $schema['type'], array( 'boolean', 'integer', 'number' ), true ) ) {
			$value = static::get_empty_value_for_type( $schema['type'] );
		}

		if ( is_wp_error( rest_validate_value_from_schema( $value, $schema ) ) ) {
			return null;
		}

		return rest_sanitize_value_from_schema( $value, $schema );
	}