docker/inspect.go
func (s NetworkSettings) PortAt(index int) (string, *HostPublish) {
	counter := 0
	for k, v := range s.Ports {
		if counter != index {
			counter++
			continue
		}

		return k, v
	}

	return "", nil
}
func (s NetworkSettings) PortAt(index int) (string, *HostPublish) {
	counter := 0
	for k, v := range s.Ports {
		if counter != index {
			counter++
			continue
		}

		return k, v
	}

	return "", nil
}
// PortAt returns expose and publish port information at especified index.