alist/pkg/utils/random/random.go

41 lines
735 B
Go

package random
import (
"crypto/rand"
"math/big"
mathRand "math/rand"
"time"
"github.com/google/uuid"
)
var Rand *mathRand.Rand
const letterBytes = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
func String(n int) string {
b := make([]byte, n)
letterLen := big.NewInt(int64(len(letterBytes)))
for i := range b {
idx, err := rand.Int(rand.Reader, letterLen)
if err != nil {
panic(err)
}
b[i] = letterBytes[idx.Int64()]
}
return string(b)
}
func Token() string {
return "alist-" + uuid.NewString() + String(64)
}
func RangeInt64(left, right int64) int64 {
return mathRand.Int63n(left+right) - left
}
func init() {
s := mathRand.NewSource(time.Now().UnixNano())
Rand = mathRand.New(s)
}