package util import ( "math/rand" ) var idCharset = []byte("abcdefghijklmnopqrstuvxyzABCDEFGHIJKLMNOPQRSTUVXYZ0123456789") func NewUUID(length int) string { id := make([]byte, length) charsetLen := int64(len(idCharset)) for i := 0; i < length; i++ { ch := rand.Int63n(charsetLen) id[i] = idCharset[ch] } return string(id) }