<?php
/**
* Base class for upgrades
*/
abstract class TawkToUpgradeBase {
const VERSION = null;
/**
* Gets current upgrade's release version
*
* @return string Release version
* @throws Exception Release version is not defined.
*/
public static function get_version() {
if ( is_null( static::VERSION ) ) {
throw new Exception( 'Subclass must have const VERSION' );
}
return static::VERSION;
}
/**
* Upgrade script
*
* @return void
* @throws Exception Subclass has no upgrade implementation.
*/
public static function upgrade() {
throw new Exception( 'Subclass must implement this!' );
}
}