MongoDB\Driver\Monitoring\CommandFailedEvent::getServiceId
  Returns the load balancer service ID for the command
  
 
  説明
  
   final public MongoDB\BSON\ObjectIdnull MongoDB\Driver\Monitoring\CommandFailedEvent::getServiceId()
  
  
 
 
  戻り値
  
   Returns the load balancer service ID, or null if the driver is not
   connected to a load balancer.
  
  
 
  エラー / 例外
  
   - Throws MongoDB\Driver\Exception\InvalidArgumentException on argument parsing errors.