在开发的过程中，我们有些接口为了防止被恶意调用，我们会采用加验证码的方式，例如：发送短信的接口，为了防止短信接口被频繁调用造成损失；注册的接口，为了防止恶意注册。在这里为大家推荐一个验证码的类库，方便大家学习使用。
github.com/dchest/captcha
web端是怎么实现验证码的功能呢？
API接口验证码实现方式类似，可以把键值对存储在起来，验证的时候把键值对传输过来一起校验。这里我只给出了web端的方法，爱动手的小伙伴可以自己尝试一下。
package main
import (
"bytes"
"github.com/dchest/captcha"
"github.com/gin-contrib/sessions"
"github.com/gin-contrib/sessions/cookie"
"github.com/gin-gonic/gin"
"net/http"
"time"
)
// 中间件，处理session
func Session(keyPairs string) gin.HandlerFunc {
store := SessionConfig()
return sessions.Sessions(keyPairs, store)
}
func SessionConfig() sessions.Store {
sessionMaxAge := 3600
sessionSecret := "topgoer"
var store sessions.Store
store = cookie.NewStore([]byte(sessionSecret))
store.Options(sessions.Options{
MaxAge: sessionMaxAge, //seconds
Path: "/",
})
return store
}
func Captcha(c *gin.Context, length ...int) {
l := captcha.DefaultLen
w, h := 107, 36
if len(length) == 1 {
l = length[0]
}
if len(length) == 2 {
w = length[1]
}
if len(length) == 3 {
h = length[2]
}
captchaId := captcha.NewLen(l)
session := sessions.Default(c)
session.Set("captcha", captchaId)
_ = session.Save()
_ = Serve(c.Writer, c.Request, captchaId, ".png", "zh", false, w, h)
}
func CaptchaVerify(c *gin.Context, code string) bool {
session := sessions.Default(c)
if captchaId := session.Get("captcha"); captchaId != nil {
session.Delete("captcha")
_ = session.Save()
if captcha.VerifyString(captchaId.(string), code) {
return true
} else {
return false
}
} else {
return false
}
}
func Serve(w http.ResponseWriter, r *http.Request, id, ext, lang string, download bool, width, height int) error {
w.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
w.Header().Set("Pragma", "no-cache")
w.Header().Set("Expires", "0")
var content bytes.Buffer
switch ext {
case ".png":
w.Header().Set("Content-Type", "image/png")
_ = captcha.WriteImage(&content, id, width, height)
case ".wav":
w.Header().Set("Content-Type", "audio/x-wav")
_ = captcha.WriteAudio(&content, id, lang)
default:
return captcha.ErrNotFound
}
if download {
w.Header().Set("Content-Type", "application/octet-stream")
}
http.ServeContent(w, r, id+ext, time.Time{}, bytes.NewReader(content.Bytes()))
return nil
}
func main() {
router := gin.Default()
router.LoadHTMLGlob("./*.html")
router.Use(Session("topgoer"))
router.GET("/captcha", func(c *gin.Context) {
Captcha(c, 4)
})
router.GET("/", func(c *gin.Context) {
c.HTML(http.StatusOK, "index.html", nil)
})
router.GET("/captcha/verify/:value", func(c *gin.Context) {
value := c.Param("value")
if CaptchaVerify(c, value) {
c.JSON(http.StatusOK, gin.H{"status": 0, "msg": "success"})
} else {
c.JSON(http.StatusOK, gin.H{"status": 1, "msg": "failed"})
}
})
router.Run(":8080")
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>www.topgoer.com验证码</title>
</head>
<body>
<img src="/captcha" onclick="this.src='/captcha?v='+Math.random()">
</body>
</html>
访问http://127.0.0.1:8080/captcha/verify/5721?进行验证
{
"msg": "failed",
"status": 1
}