captcha

Documentation

Index

• Constants
• Variables
• func New() string
• func NewLen(length int) string
• func NewLenChars(length int, chars []byte) string
• type Image
  • func Fetch() (*Image, string)
  • func NewImage(digits []byte, width, height int) *Image
  • func (img *Image) WriteTo(w io.Writer) (int64, error)

Constants

const (
	// StdLen Standard length of uniuri string to achive ~95 bits of entropy.
	StdLen = 16
	// UUIDLen Length of uniurl string to achive ~119 bits of entropy, closest
	// to what can be losslessly converted to UUIDv4 (122 bits).
	UUIDLen = 20
)

Variables

var StdChars = []byte("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789")

StdChars Standard characters allowed in uniuri string.

Functions

func New

func New() string

New returns a new random string of the standard length, consisting of standard characters.

func NewLen

func NewLen(length int) string

NewLen returns a new random string of the provided length, consisting of standard characters.

func NewLenChars

func NewLenChars(length int, chars []byte) string

NewLenChars returns a new random string of the provided length, consisting of the provided byte slice of allowed characters (maximum 256).

Types

type Image

type Image struct {
	*image.NRGBA
	// contains filtered or unexported fields
}

Image image struct

func Fetch

func Fetch() (*Image, string)

Fetch gen a captcha image

func NewImage

func NewImage(digits []byte, width, height int) *Image

NewImage create a new image

func (*Image) WriteTo

func (img *Image) WriteTo(w io.Writer) (int64, error)

WriteTo write into image