[Wiki] MigrateCommand class for multiple sites using one code base

class XMigrateCommand extends MigrateCommand
{
    public $domain = '';
    protected $_db;
 
    public function beforeAction($action,$params)
    {
        if (in_array(strtolower($action),array('up','down','safeup','safedown','redo','to','new','history','mark')) && $this->domain == '')
        {
            echo 'You need to specify the domain as Xpress support multi-sites and multi-database.',"\n",'i.e: --domain=www.domain.com',"\n";
            return false;
        }
 
        return parent::beforeAction($action,$params);
    }
 
    protected function getDbConnection()
    {
        if($this->_db!==null)
            return $this->_db;
        else
        {        
            // environment file locates in /sites/env folder using this naming convention: config.domain.php
            $envFile = 'config.'.$this->domain.'.php';
            $envFile = Yii::app()->basePath.'/../sites/env/'.$envFile;
            if (file_exists($envFile))
            {
                include ($envFile);
                $db = $dbs['default'];
                $this->_db = new CDbConnection($db['connectionString'],$db['username'],$db['password']);
                return $this->_db;
            }
            else
            {
                echo "Error: {$envFile} is not found. Invalid domain or this domain is not configured properly.";
                exit(1);
            }
        }
 
        echo "Error: CMigrationCommand.connectionID '{$this->connectionID}' is invalid. Please make sure it refers to the ID of a CDbConnection application component.\n";
        exit(1);
    }
}

$dbs['default']['connectionString'] = 'mysql:...';
$dbs['default']['username'] = 'username';
$dbs['default']['password'] = 'password';