pkg: added random string, peer

pkg/random/string.go

@@ -0,0 +1,26 @@
+// Copyright 2016 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package random
+
+import "math/rand"
+
+// AlphaNumeric is an alphabet with all lower- and uppercase letters and
+// numbers.
+const AlphaNumeric = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+
+// AlphaNumericString is a shorthand for String(r, l, AlphaNumeric).
+func AlphaNumericString(r rand.Source, l int) string {
+	return String(r, l, AlphaNumeric)
+}
+
+// String generates a random string of length l, containing only runes from
+// the alphabet using the random source r.
+func String(r rand.Source, l int, alphabet string) string {
+	b := make([]byte, l)
+	for i := range b {
+		b[i] = alphabet[r.Int63()%int64(len(alphabet))]
+	}
+	return string(b)
+}