操作系统: CentOS 6.9_x64
go语言版本: 1.8.3
问题描述
golang没有提供生成uuid的接口,但开发中确实需要uuid。
这里把看到的代码记录下,也方便我以后查阅。
解决方案
示例代码如下:
package main import ( "fmt" "sync/atomic" "time" ) type UUID [16]byte var timeBase = time.Date(1582, time.October, 15, 0, 0, 0, 0, time.UTC).Unix() var hardwareAddr []byte var clockSeq uint32 func TimeUUID() UUID { return FromTime(time.Now()) } func FromTime(aTime time.Time) UUID { var u UUID utcTime := aTime.In(time.UTC) t := uint64(utcTime.Unix()-timeBase)*10000000 + uint64(utcTime.Nanosecond()/100) u[0], u[1], u[2], u[3] = byte(t>>24), byte(t>>16), byte(t>>8), byte(t) u[4], u[5] = byte(t>>40), byte(t>>32) u[6], u[7] = byte(t>>56)&0x0F, byte(t>>48) clock := atomic.AddUint32(&clockSeq, 1) u[8] = byte(clock >> 8) u[9] = byte(clock) copy(u[10:], hardwareAddr) u[6] |= 0x10 // set version to 1 (time based uuid) u[8] &= 0x3F // clear variant u[8] |= 0x80 // set to IETF variant return u } func (u UUID) String() string { var offsets = [...]int{ 0, 2, 4, 6, 9, 11, 14, 16, 19, 21, 24, 26, 28, 30, 32, 34} const hexString = "0123456789abcdef" r := make([]byte, 36) for i, b := range u { r[offsets[i]] = hexString[b>>4] r[offsets[i]+1] = hexString[b&0xF] } r[8] = '-' r[13] = '-' r[18] = '-' r[23] = '-' return string(r) } func main() { out := TimeUUID() fmt.Printf("%s\n", out.String()) }
运行效果:
[root@local t2]# go run uuidTest.go [root@local t2]# 3e42d638-5243-11e7-8001-000000000000
讨论
当然如果你只是想快速的得到uuid,而且使用的是linux系统,可以直接使用uuidgen命令来获取。
示例代码如下:
package main import ( "fmt" "log" "os/exec" ) //run in linux func main() { out, err := exec.Command("uuidgen").Output() if err != nil { log.Fatal(err) } fmt.Printf("%s", out) }
好,就这些了,希望对你有帮助。
本文github地址:
https://github.com/mike-zhang/mikeBlogEssays/blob/master/2017/20170615_go语言生成uuid.rst
欢迎补充