让uuid更有意义

Author: c-wind

uuid/uuid.go

@@ -3,15 +3,16 @@ package uuid
 import (
 	"encoding/base32"
 	"encoding/binary"
+	"fmt"
 	"net"
 	"os"
 	"sync/atomic"
 	"time"
 )
 
 var (
-	inc uint32
-	buf = make([]byte, 16)
+	seq uint32
+	buf = make([]byte, 14)
 )
 
 func init() {
@@ -21,19 +22,46 @@ func init() {
 			if !i.IP.IsLoopback() {
 				i4 := i.IP.To4()
 				if len(i4) == net.IPv4len {
-					buf[0] = i.IP.To4()[2]
-					buf[1] = i.IP.To4()[3]
+					buf[4] = i.IP.To4()[0]
+					buf[5] = i.IP.To4()[1]
+					buf[6] = i.IP.To4()[2]
+					buf[7] = i.IP.To4()[3]
 					break
 				}
 			}
 		}
 	}
-	binary.LittleEndian.PutUint16(buf[2:], uint16(os.Getpid()))
+	binary.LittleEndian.PutUint16(buf[8:], uint16(os.Getpid()))
 }
 
 //String 生成字符串的uuid
 func String() string {
-	binary.BigEndian.PutUint64(buf[4:], uint64(time.Now().Unix()))
-	binary.BigEndian.PutUint32(buf[12:], atomic.AddUint32(&inc, 1))
+	binary.BigEndian.PutUint32(buf[0:], uint32(time.Now().UTC().Unix()))
+	binary.BigEndian.PutUint32(buf[10:], atomic.AddUint32(&seq, 1))
 	return base32.HexEncoding.WithPadding(base32.NoPadding).EncodeToString(buf)
 }
+
+//Decode 解析uuid字符串，返回具体细节.
+func Decode(s string) (ip string, pid int, tm time.Time, seq uint32, err error) {
+	var buf []byte
+	buf, err = base32.HexEncoding.WithPadding(base32.NoPadding).DecodeString(s)
+	if err != nil {
+		return
+	}
+
+	tm = time.Unix(int64(binary.BigEndian.Uint32(buf)), 0)
+	ip = net.IPv4(buf[4], buf[5], buf[6], buf[7]).String()
+	pid = int(binary.LittleEndian.Uint16(buf[8:]))
+	seq = binary.BigEndian.Uint32(buf[10:])
+
+	return
+}
+
+//Info 解析uuid中信息.
+func Info(s string) (string, error) {
+	ip, pid, tm, seq, err := Decode(s)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("ip:%s pid:%d time:%s sequence:%d", ip, pid, tm.Format(time.RFC3339), seq), nil
+}

uuid/uuid_test.go

@@ -6,7 +6,8 @@ import (
 
 func TestUUID(t *testing.T) {
 	for i := 0; i < 1000; i++ {
-		t.Logf("%s", String())
+		id := String()
+		info, _ := Info(id)
+		t.Logf("%s, %s", id, info)
 	}
-
 }