code: func NewConnectionProducer(factory ConnectionFactory, endpoints []string) ConnectionProducer {
  	if len(endpoints) == 0 {
  		return nil
  	}
  	return &connProducer{endpoints: endpoints, connect: factory, disabledEndpoints: make(map[string]time.Time)}
  }
docs: // NewConnectionProducer creates a new ConnectionProducer with given endpoints and connection factory.
  // It returns nil, if the given endpoints slice is empty.