README
¶
Captchas
Base64 Captchas Manager, supports multiple drivers(digit, math, audio, string, chinese etc.) and stores(memory, redis, memcached etc.).
Usage
Preview: http://129.204.189.159:10000/.
$ cd example
$ go run main.go
Quick Start
package main
import (
"encoding/json"
"fmt"
"io"
"log"
"net/http"
"text/template"
"github.com/clevergo/captchas"
"github.com/clevergo/captchas/drivers"
"github.com/clevergo/captchas/memstore"
)
var (
store = memstore.New() // memory store.
driver = drivers.NewDigit() // digit driver.
manager = captchas.New(store, driver) // manager
tmpl = template.Must(template.New("captcha").Parse(`
<html>
<body>
<form action="/validate" method="POST">
<input name="captcha">
{{ .captcha.HTMLField "captcha_id" }}
<input type="submit" value="Submit">
</form>
</body>
</html>
`))
)
func main() {
http.HandleFunc("/generate", generate)
http.HandleFunc("/validate", validate)
log.Println(http.ListenAndServe(":8080", http.DefaultServeMux))
}
// generates a new captcha
func generate(w http.ResponseWriter, r *http.Request) {
captcha, err := manager.Generate()
if err != nil {
http.Error(w, err.Error(), 500)
return
}
// returns JSON data.
if r.URL.Query().Get("format") == "json" {
v := map[string]string{
"captcha_id": captcha.ID(), // captcha ID.
"captcha_data": captcha.EncodeToString(), // base64 encode string.
}
data, _ := json.Marshal(v)
w.Write(data)
return
}
// render captcha via template.
tmpl.Execute(w, map[string]interface{}{
"captcha": captcha,
})
}
// validates a captcha.
func validate(w http.ResponseWriter, r *http.Request) {
captchaID := r.PostFormValue("captcha_id")
captcha := r.PostFormValue("captcha")
// verify
if err := manager.Verify(captchaID, captcha, true); err != nil {
io.WriteString(w, fmt.Sprintf("captcha is invalid: %s", err.Error()))
return
}
io.WriteString(w, "valid")
}
Drivers
import "github.com/clevergo/captchas/drivers"
Digit
// all options are optional.
opts := []drivers.DigitOption{
drivers.DigitHeight(50),
drivers.DigitWidth(120),
drivers.DigitLength(6),
drivers.DigitMaxSkew(0.8),
drivers.DigitDotCount(80),
}
driver := drivers.NewDigit(opts...)
Audio
// all options are optional.
opts := []drivers.AudioOption{
drivers.AudioLangauge("en"),
drivers.AudioLength(6),
}
driver := drivers.NewAudio(opts...)
Math
// all options are optional.
opts := []drivers.MathOption{
drivers.MathHeight(50),
drivers.MathWidth(120),
drivers.MathNoiseCount(0),
drivers.MathFonts([]string{}),
drivers.MathBGColor(&color.RGBA{}),
}
driver := drivers.NewMath(opts...)
String
// all options are optional.
opts := []drivers.StringOption{
drivers.StringHeight(50),
drivers.StringWidth(120),
drivers.StringLength(4),
drivers.StringNoiseCount(0),
drivers.StringFonts([]string{}),
drivers.StringSource("abcdefghijklmnopqrstuvwxyz"),
drivers.StringBGColor(&color.RGBA{}),
}
driver := drivers.NewString(opts...)
Chinese
// all options are optional.
opts := []drivers.ChineseOption{
drivers.ChineseHeight(50),
drivers.ChineseWidth(120),
drivers.ChineseLength(4),
drivers.ChineseNoiseCount(0),
drivers.ChineseFonts([]string{"wqy-microhei.ttc"}),
drivers.ChineseSource("零一二三四五六七八九十"),
drivers.ChineseBGColor(&color.RGBA{}),
}
driver := drivers.NewChinese(opts...)
Stores
- memory
- redis
- memcached
- add your store here by PR or request a new store.
Memory
import "github.com/clevergo/captchas/memstore"
store := memstore.New(
memstore.Expiration(10*time.Minute), // captcha expiration, optional.
memstore.GCInterval(time.Minute), // garbage collection interval to delete expired captcha, optional.
)
Inspired by scs.memstore.
Redis
import (
"github.com/clevergo/captchas/redisstore"
"github.com/go-redis/redis/v7"
)
// redis client.
client := redis.NewClient(&redis.Options{
Addr: "localhost:6379",
})
store := redisstore.New(
client,
redisstore.Expiration(expiration), // captcha expiration, optional.
redisstore.Prefix("caotchas"), // redis key prefix, optional.
)
Memcached
import (
"github.com/bradfitz/gomemcache/memcache"
"github.com/clevergo/captchas/memcachedstore"
)
// client.
client := memcache.New("localhost:11211")
store := memcachedstore.New(
client,
memcachedstore.Expiration(int32(600)), // captcha expiration, optional.
memcachedstore.Prefix("captchas"), // key prefix, optional.
)
Documentation
¶
Index ¶
Constants ¶
This section is empty.
Variables ¶
View Source
var ( ErrCaptchaIncorrect = errors.New("captcha is incorrect") ErrCaptchaExpired = errors.New("captcha is expired") )
Errors
Functions ¶
This section is empty.
Types ¶
type Captcha ¶
type Captcha interface {
// ID returns captcha ID.
ID() string
// Answer returns captcha answer.
Answer() string
// EncodeToString returns encoded base64 string.
EncodeToString() string
// HTMLField returns a template.HTML that includes captcha ID hidden input field
// and media field(audio/img).
HTMLField(fieldName string) template.HTML
}
Captcha is an interface that captchas that generated by driver should implements.
type Driver ¶
type Driver interface {
// Generate generates a new captcha, returns an error if failed.
Generate() (Captcha, error)
}
Driver defines how to generate captchas.
type Manager ¶
type Manager struct {
// contains filtered or unexported fields
}
Manager is a captchas manager.
func (*Manager) Generate ¶
Generate generates a new captcha and save it to store, returns an error if failed.
type Option ¶
type Option func(*Manager)
Option is a function that receives a pointer of manager.
func CaseSensitive ¶
CaseSensitive is an option that enable or disable case sensitive.
type Store ¶
type Store interface {
// Get returns the answer of the given captcha ID, returns
// an error if failed. Clear indicates whether delete the
// captcha after fetching.
Get(id string, clear bool) (string, error)
// Set saves the captcha ID and answer, returns error
// if failed.
Set(id, answer string) error
}
Store defines how to save and load captcha information.
Source Files
Directories
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| Path | Synopsis |
|---|---|
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drivers
module
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memcachedstore
module
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memstore
module
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redisstore
module
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stores
|
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dbstore
Module
|
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memcachedstore
Module
|
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memstore
Module
|
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redisstore
Module
|
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