/
uuid.go
41 lines (38 loc) · 1.38 KB
/
uuid.go
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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package utils
import (
"crypto/rand"
"fmt"
)
// GenerateUUID generates an uuid
// https://tools.ietf.org/html/rfc4122
// crypto.rand use getrandom(2) or /dev/urandom
// It is maybe occur an error due to system error
// panic if an error occurred
func GenerateUUID() string {
uuid := make([]byte, 16)
_, err := rand.Read(uuid)
if err != nil {
panic("generate an uuid failed, error: " + err.Error())
}
// see section 4.1.1
uuid[8] = uuid[8]&^0xc0 | 0x80
// see section 4.1.3
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:])
}