private function checkCapabilities(Predis_Client $redisClient)
{
if (Predis_Shared_Utils::isCluster($redisClient->getConnection())) {
throw new Predis_ClientException('Cannot initialize a PUB/SUB context over a cluster of connections');
}
$profile = $redisClient->getProfile();
$commands = array('publish', 'subscribe', 'unsubscribe', 'psubscribe', 'punsubscribe');
if ($profile->supportsCommands($commands) === false) {
throw new Predis_ClientException('The current profile does not support PUB/SUB related commands');
}
}