dhcpd_leases golang parser example

dhcpd_leases.go

package main


import (
	"encoding/json"
	"strings"
	"bufio"
	"fmt"
	"os"
)


const (
	filename = "/var/db/dhcpd_leases"
)

var (
	leases = []Lease{}
)


type Lease struct {
	ID         string
	Name       string
	IPAddress  string
	MACAddress string
	Identifier string
}


// FromString("name=localhost	ip_address=192.168.64.2	hw_address=1,62:8:cb:94:c3:b3	identifier=1,62:8:cb:94:c3:b3	lease=0x5e41f346") (lease)
func FromString(src string) Lease {
	self := Lease{}
	for _, some := range strings.Split(src, "\t") {

		if some == "" {
			continue
		}

		line := strings.Split(some, "=")

		switch line[0] {
		default:
			continue
		case "name":
			self.Name = line[1]
		case "ip_address":
			self.IPAddress = line[1]
		case "hw_address":
			self.MACAddress = line[1]
		case "identifier":
			self.Identifier = line[1]
		case "lease":
			self.ID = line[1]
		}

	}

	return self
}


func main() {
	fileHandle, _ := os.Open(filename)
	defer fileHandle.Close()
	fileScanner := bufio.NewScanner(fileHandle)

	block := ""

	for fileScanner.Scan() {
		line := fileScanner.Text()
		switch line {
  		case "":
  			continue
  		case "{":
  			block = ""
  		case "}":
  			leases = append(leases, FromString(block))
  		default:
  			block += line
		}
	}

	b, _ := json.Marshal(leases)

	fmt.Println(string(b))
}