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依赖的包

go get -u github.com/mojocn/base64Captcha

文档地址

https://mojotv.cn/go/refactor-base64-captcha

DEMO展示地址，按F12查看参数及返回信息

https://captcha.mojotv.cn/

刚开始运行的时候出现报错

invalid memory address or nil pointer dereference goroutinethe demo main.go must run with the frontend html file , otherwise there is no HTTP-Request-JSON-Config-Body param being POST to the go server and that makes the golang-captcha config is not fully initialized

其实是参数传递问题，于是参考DEMO网站使用如下参数

采用 body raw 的方式传递json串

{
   "ShowLineOptions":["4","2","8"],"CaptchaType":"string","Id":"1ENJhuUtbyvCQozSQmE2","VerifyValue":"","DriverAudio":{
   "Length":6,"Language":"zh"},"DriverString":{
   "Height":60,"Width":245,"ShowLineOptions":14,"NoiseCount":0,"Source":"1234567890","Length":4,"Fonts":["ApothecaryFont.ttf","DeborahFancyDress.ttf","Flim-Flam.ttf","wqy-microhei.ttc"],"BgColor":{
   "R":0,"G":0,"B":0,"A":0}},"DriverMath":{
   "Height":60,"Width":240,"ShowLineOptions":14,"NoiseCount":0,"Length":6,"Fonts":["wqy-microhei.ttc"],"BgColor":{
   "R":0,"G":0,"B":0,"A":0}},"DriverChinese":{
   "Height":60,"Width":320,"ShowLineOptions":0,"NoiseCount":0,"Source":"设想,你在,处理,消费者,的音,频输,出音,频可,能无,论什,么都,没有,任何,输出,或者,它可,能是,单声道,立体声,或是,环绕立,体声的,,不想要,的值","Length":2,"Fonts":["wqy-microhei.ttc"],"BgColor":{
   "R":125,"G":125,"B":0,"A":118}},"DriverDigit":{
   "Height":80,"Width":240,"Length":5,"MaxSkew":0.7,"DotCount":80}}

选择数字验证码 digital

{
   "ShowLineOptions":["4","2","8"],"CaptchaType":"digit","Id":"vzFYDhJTKtFYgBQz6Jo4","VerifyValue":"","DriverAudio":{
   "Length":6,"Language":"zh"},"DriverString":{
   "Height":60,"Width":245,"ShowLineOptions":14,"NoiseCount":0,"Source":"1234567890","Length":4,"Fonts":["ApothecaryFont.ttf","DeborahFancyDress.ttf","Flim-Flam.ttf","wqy-microhei.ttc"],"BgColor":{
   "R":0,"G":0,"B":0,"A":0}},"DriverMath":{
   "Height":60,"Width":240,"ShowLineOptions":14,"NoiseCount":0,"Length":6,"Fonts":["wqy-microhei.ttc"],"BgColor":{
   "R":0,"G":0,"B":0,"A":0}},"DriverChinese":{
   "Height":60,"Width":320,"ShowLineOptions":0,"NoiseCount":0,"Source":"设想,你在,处理,消费者,的音,频输,出音,频可,能无,论什,么都,没有,任何,输出,或者,它可,能是,单声道,立体声,或是,环绕立,体声的,,不想要,的值","Length":2,"Fonts":["wqy-microhei.ttc"],"BgColor":{
   "R":125,"G":125,"B":0,"A":118}},"DriverDigit":{
   "Height":80,"Width":240,"Length":4,"MaxSkew":0.7,"DotCount":80}}

精简后

{
   "CaptchaType":"digit","Id":"vzFYDhJTKtFYgBQz6Jo4","VerifyValue":"","DriverDigit":{
   "Height":80,"Width":240,"Length":4,"MaxSkew":0.7,"DotCount":80}}

接下来对验证码的使用做一个封装，方便调用。

1、使用redis驱动存储验证码。 2、只使用数组验证码。 3、使用带有用户标识的key代替默认的随机的key来存储验证码。

captcha.go 文件

package captchaimport (	"math/rand"	"time"	"github.com/mojocn/base64Captcha")func init() {
   	rand.Seed(time.Now().UnixNano())}type configJsonBody struct {
   	Id            string	CaptchaType   string	VerifyValue   string	DriverAudio   *base64Captcha.DriverAudio	DriverString  *base64Captcha.DriverString	DriverChinese *base64Captcha.DriverChinese	DriverMath    *base64Captcha.DriverMath	DriverDigit   *base64Captcha.DriverDigit}var store = RedisStore{
   }//var store = base64Captcha.DefaultMemStore// 使用 digit// key 为用户标识，比如手机号，token, openid等func Generate(key string) (id string, b64s string, err error) {
   	//parse request parameters	param := configJsonBody{
   		Id:          "",		CaptchaType: "digit",		VerifyValue: "",		DriverDigit: &base64Captcha.DriverDigit{
   			Height:   80,			Width:    240,			Length:   4,			MaxSkew:  0.7,			DotCount: 80,		},	}	var driver base64Captcha.Driver	//create base64 encoding captcha	switch param.CaptchaType {
   	case "audio":		driver = param.DriverAudio	case "string":		driver = param.DriverString.ConvertFonts()	case "math":		driver = param.DriverMath.ConvertFonts()	case "chinese":		driver = param.DriverChinese.ConvertFonts()	default:		driver = param.DriverDigit	}	c := base64Captcha.NewCaptcha(driver, store)	// 默认的方式下，id是随机生产的，现在改成定制的id	//id, b64s, err := c.Generate()	id, content, answer := c.Driver.GenerateIdQuestionAnswer()	item, err := c.Driver.DrawCaptcha(content)	if err != nil {
   		return "", "", err	}	// 使用key代替id来存储验证码	c.Store.Set(key, answer)	b64s = item.EncodeB64string()	return id, b64s, err}func Verify(id string, VerifyValue string) (res bool) {
   	//parse request json body	param := configJsonBody{
   		Id:          id,		CaptchaType: "digit",		VerifyValue: VerifyValue,		DriverDigit: &base64Captcha.DriverDigit{
   			Height:   80,			Width:    240,			Length:   4,			MaxSkew:  0.7,			DotCount: 80,		},	}	//verify the captcha	return store.Verify(param.Id, param.VerifyValue, true)}

RedisStore.go 文件

package captchaimport (	"strconv"	"voteapi/pkg/gredis")const CAPTCHA = "captcha:"type RedisStore struct {
   }// 存储的是 "8926" 而不是 8926，需要转换一下func (r RedisStore) Set(id string, value string) {
   	v ,_ := strconv.Atoi(value)	gredis.Set(CAPTCHA + id, v, 180)}func (r RedisStore) Get(id string, clear bool) string {
   	key := CAPTCHA + id	re, err := gredis.Get(key)	if err != nil {
   		return ""	}	if clear {
   		gredis.Delete(key)	}	return string(re)}func (r RedisStore) Verify(id, answer string, clear bool) bool {
   	v := RedisStore{
   }.Get(id, clear)	return v == answer}

调用验证码

func Captcha(c *gin.Context) {
   	key := c.DefaultQuery("key", "")	if key == "" {
   		response.JsonResponseError(c, "参数错误")		return	}	id, b64s, err := captcha.Generate(util.Md5(key))	if err != nil {
   		response.JsonResponseError(c, err.Error())		return	}	body := make(map[string]interface{
   })	body["id"] = id	body["b64s"] = b64s	response.JsonResponseSuccess(c, body)}

校验验证码

if !captcha.Verify(captchaKey, verifyCode) {
   	return votedArr, errors.New("验证码校验失败")}

转载地址：http://bcaui.baihongyu.com/