main.go

package main

import (
	"encoding/binary"
	"fmt"
	"math/rand"
	"net"
	"strconv"
	"strings"
	"time"
)

func main() {
	spanId := GenerateSpanID(GetLocalIP().String())
	traceId := GenerateTraceID(GetLocalIP().String())
	fmt.Println("traceId: " + traceId, "spanId: " + spanId)

}



func GenerateSpanID(addr string) string {
	strAddr := strings.Split(addr, ":")
	ip := strAddr[0]
	ipLong, _ := Ip2Long(ip)
	times := uint64(time.Now().UnixNano())
	spanId := ((times ^ uint64(ipLong)) << 32) | uint64(rand.Int31())
	return strconv.FormatUint(spanId, 16)
}

func GenerateTraceID(addr string) string {
	strAddr := strings.Split(addr, ":")
	ip := strAddr[0]
	ipLong, _ := Ip2Long(ip)
	times := uint64(time.Now().UnixNano())
	traceId := ((times ^ uint64(ipLong)) << 32) | uint64(rand.Int31())
	return strconv.FormatUint(traceId, 16)
}

func Ip2Long(ip string) (uint32, error) {
	ipAddr, err := net.ResolveIPAddr("ip", ip)
	if err != nil {
		return 0, err
	}
	return binary.BigEndian.Uint32(ipAddr.IP.To4()), nil
}

func GetLocalIP() net.IP {
	addrs, err := net.InterfaceAddrs()
	if err != nil {
		return net.IPv4zero
	}
	for _, a := range addrs {
		if ipnet, ok := a.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
			if ip := ipnet.IP.To4(); ip != nil {
				return ipnet.IP
			}
		}
	}
	return net.IPv4zero
}