rand func modify

utils/rand.go

@@ -20,28 +20,24 @@ import (
 	"time"
 )
 
+var alphaNum = []byte(`0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz`)
+
 // RandomCreateBytes generate random []byte by specify chars.
 func RandomCreateBytes(n int, alphabets ...byte) []byte {
-	const alphanum = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+	if len(alphabets) == 0 {
+		alphabets = alphaNum
+	}
 	var bytes = make([]byte, n)
-	var randby bool
+	var randBy bool
 	if num, err := rand.Read(bytes); num != n || err != nil {
 		r.Seed(time.Now().UnixNano())
-		randby = true
+		randBy = true
 	}
 	for i, b := range bytes {
-		if len(alphabets) == 0 {
-			if randby {
-				bytes[i] = alphanum[r.Intn(len(alphanum))]
-			} else {
-				bytes[i] = alphanum[b%byte(len(alphanum))]
-			}
+		if randBy {
+			bytes[i] = alphabets[r.Intn(len(alphabets))]
 		} else {
-			if randby {
-				bytes[i] = alphabets[r.Intn(len(alphabets))]
-			} else {
-				bytes[i] = alphabets[b%byte(len(alphabets))]
-			}
+			bytes[i] = alphabets[b%byte(len(alphabets))]
 		}
 	}
 	return bytes