From a19a8615525cd4e5ec3b5721e41089ca1c0e6be2 Mon Sep 17 00:00:00 2001
From: dudaodong <lanliddd.2007@163.com>
Date: Sun, 20 Feb 2022 10:16:15 +0800
Subject: [PATCH] feat: add func UUIdV4

---
 random/random.go      | 16 ++++++++++++++++
 random/random_test.go | 13 +++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/random/random.go b/random/random.go
index ebd708d..d84f5d3 100644
--- a/random/random.go
+++ b/random/random.go
@@ -6,6 +6,7 @@ package random
 
 import (
 	crand "crypto/rand"
+	"fmt"
 	"io"
 	"math/rand"
 	"time"
@@ -48,3 +49,18 @@ func RandBytes(length int) []byte {
 	}
 	return b
 }
+
+// UUIdV4 generate a random UUID of version 4 according to RFC 4122
+func UUIdV4() (string, error) {
+	uuid := make([]byte, 16)
+
+	n, err := io.ReadFull(crand.Reader, uuid)
+	if n != len(uuid) || err != nil {
+		return "", err
+	}
+
+	uuid[8] = uuid[8]&^0xc0 | 0x80
+	uuid[6] = uuid[6]&^0xf0 | 0x40
+
+	return fmt.Sprintf("%x-%x-%x-%x-%x", uuid[0:4], uuid[4:6], uuid[6:8], uuid[8:10], uuid[10:]), nil
+}
diff --git a/random/random_test.go b/random/random_test.go
index 190113c..82fc19a 100644
--- a/random/random_test.go
+++ b/random/random_test.go
@@ -47,3 +47,16 @@ func TestRandBytes(t *testing.T) {
 
 	assert.Equal([]byte{}, RandBytes(0))
 }
+
+func TestUUIdV4(t *testing.T) {
+	assert := internal.NewAssert(t, "TestUUIdV4")
+
+	uuid, err := UUIdV4()
+	if err != nil {
+		t.Log(err)
+		t.Fail()
+	}
+
+	isUUiDV4 := regexp.MustCompile(`^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-4[0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}$`)
+	assert.Equal(true, isUUiDV4.MatchString(uuid))
+}