// generateRandomKey creates a random key with the given strength.
func generateRandomKey(strength int) []byte {
k := make([]byte, strength)
if n, err := io.ReadFull(rand.Reader, k); n != strength || err != nil {
return utils.RandomCreateBytes(strength)
}
return k
}
func BenchmarkNewImage(b *testing.B) {
b.StopTimer()
d := utils.RandomCreateBytes(challengeNums, defaultChars...)
b.StartTimer()
for i := 0; i < b.N; i++ {
NewImage(d, stdWidth, stdHeight)
}
}
func BenchmarkImageWriteTo(b *testing.B) {
b.StopTimer()
d := utils.RandomCreateBytes(challengeNums, defaultChars...)
b.StartTimer()
counter := &byteCounter{}
for i := 0; i < b.N; i++ {
img := NewImage(d, stdWidth, stdHeight)
img.WriteTo(counter)
b.SetBytes(counter.n)
counter.n = 0
}
}
// create a new captcha id
func (c *Captcha) CreateCaptcha() (string, error) {
// generate captcha id
id := string(utils.RandomCreateBytes(15))
// get the captcha chars
chars := c.genRandChars()
// save to store
if err := c.store.Put(c.key(id), chars, c.Expiration); err != nil {
return "", err
}
return id, nil
}
// generate rand chars with default chars
func (c *Captcha) genRandChars() []byte {
return utils.RandomCreateBytes(c.ChallengeNums, defaultChars...)
}