nerds/store/random.go

package store

import (
	"crypto/rand"
)

// Generate62RandomString creates a random string with the given length
// consisting of characters in [A-Za-z0-9].
func Generate62RandomString(l int) string {
	return GenerateRandomString("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz", l)
}

// GenerateFriendlyRandomString creates a random string of characters with the
// given length consististing of characters in [a-z0-9].
func GenerateFriendlyRandomString(l int) string {
	return GenerateRandomString("0123456789abcdefghijklmnopqrstuvwxyz", l)
}

// GenerateRandomString creates a random string of characters of the given
// length from the given dictionary of possible characters.
//
// This example generates a hexadecimal string 6 characters long:
//     GenerateRandomString("0123456789abcdef", 6)
func GenerateRandomString(dictionary string, l int) string {
	var bytes = make([]byte, l)
	rand.Read(bytes)
	for k, v := range bytes {
		bytes[k] = dictionary[v%byte(len(dictionary))]
	}
	return string(bytes)
}