onWebSocketConnect 设置的的SESSION 在 onConnect 如何能取到

$gateway->onConnect = function($connection)
{
    $connection->onWebSocketConnect = function($connection , $http_header)
    {
        $_SESSION = substr($_SERVER, 1);
    };
};

public static function onConnect($client_id){
        $session = Gateway::getSession($client_id);
        Gateway::bindUid($client_id,$session);
        Gateway::sendToAll($session." 进入");
    }