DockerCLI/opts/ip.go

43 lines
934 B
Go

package opts
import (
"fmt"
"net"
)
// IPOpt holds an IP. It is used to store values from CLI flags.
type IPOpt struct {
*net.IP
}
// NewIPOpt creates a new IPOpt from a reference net.IP and a
// string representation of an IP. If the string is not a valid
// IP it will fallback to the specified reference.
func NewIPOpt(ref *net.IP, defaultVal string) *IPOpt {
o := &IPOpt{
IP: ref,
}
o.Set(defaultVal)
return o
}
// Set sets an IPv4 or IPv6 address from a given string. If the given
// string is not parseable as an IP address it returns an error.
func (o *IPOpt) Set(val string) error {
ip := net.ParseIP(val)
if ip == nil {
return fmt.Errorf("%s is not an ip address", val)
}
*o.IP = ip
return nil
}
// String returns the IP address stored in the IPOpt. If stored IP is a
// nil pointer, it returns an empty string.
func (o *IPOpt) String() string {
if *o.IP == nil {
return ""
}
return o.IP.String()
}