date.chapril.org-framadate/app/classes/Framadate/Migration/Migration.php

<?php
namespace Framadate\Migration;

interface Migration {

    /**
     * This method could check if the execute method should be called.
     * It is called before the execute method.
     *
     * @param \PDO $pdo The connection to database
     * @return bool true is the Migration should be executed.
     */
    function preCondition(\PDO $pdo);

    /**
     * This methode is called only one time in the migration page.
     *
     * @param \PDO $pdo The connection to database
     * @return bool true is the execution succeeded
     */
    function execute(\PDO $pdo);

}