/**
  * @param PoolingShardConnection $connection
  * @return Success|Failure
  */
 private function checkPoolingShardConnection(PoolingShardConnection $connection)
 {
     // TODO Check all shards, instead of just the active one.
     $isConnected = $connection->ping();
     $data = [$connection->getActiveShardId() => $isConnected ? 'connected' : 'not connected'];
     if ($isConnected) {
         return new Success(get_class($connection), $data);
     }
     return new Failure(get_class($connection), $data);
 }