Golang：使用Base64Captcha生成数字字母验证码实现安全校验

Base64Captcha可以在服务端生成验证码，以base64的格式返回

为了能看到生成的base64验证码图片，我们借助gin

go get -u github.com/mojocn/base64Captcha
go get -u github.com/gin-gonic/gin

文档的示例看起来很复杂，下面，通过简单的一个小实例，来展示Base64Captcha的基本使用

项目示例

目录结构

main.go
captcha_util/captcha_util.go
templates/index.html

先写一个工具类，将base64Captcha进行简单的封装，实现主要的功能：生成验证码和验证验证码

package captcha_utilimport ("github.com/mojocn/base64Captcha"
)// 验证码工具类
type StringCaptcha struct {captcha *base64Captcha.Captcha
}// 创建验证码
func NewCaptcha() *StringCaptcha {// storestore := base64Captcha.DefaultMemStore// 包含数字和字母的字符集source := "123456789abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ"// driverdriver := base64Captcha.NewDriverString(80,     // height int240,    // width int6,      // noiseCount int1,      // showLineOptions int4,      // length intsource, // source stringnil,    // bgColor *color.RGBAnil,    // fontsStorage FontsStoragenil,    // fonts []string)captcha := base64Captcha.NewCaptcha(driver, store)return &StringCaptcha{captcha: captcha,}
}// 生成验证码
func (stringCaptcha *StringCaptcha) Generate() (string, string, string) {id, b64s, answer, _ := stringCaptcha.captcha.Generate()return id, b64s, answer
}// 验证验证码
func (stringCaptcha *StringCaptcha) Verify(id string, answer string) bool {return stringCaptcha.captcha.Verify(id, answer, true)
}

通过gin的两个路由，分别输出验证码 和验证验证码

package mainimport ("demo/captcha_util""fmt""html/template""net/http""github.com/gin-gonic/gin"
)func main() {app := gin.Default()// 加载模板文件app.LoadHTMLGlob("templates/*")// 验证码stringCaptcha := captcha_util.NewCaptcha()// 生成验证码app.GET("/generate", func(ctx *gin.Context) {id, b64s, answer := stringCaptcha.Generate()fmt.Println(answer)ctx.HTML(http.StatusOK, "index.html", gin.H{"captchaId": id,"b64s":      template.URL(b64s),"answer":    answer,})})// 验证app.POST("/verify", func(ctx *gin.Context) {answer := ctx.PostForm("answer")captchaId := ctx.PostForm("captchaId")result := stringCaptcha.Verify(captchaId, answer)ctx.JSON(http.StatusOK, gin.H{"captchaId": captchaId,"answer":    answer,"result":    result,})})// 监听并在 http://127.0.0.1:8080 上启动服务app.Run()
}

index.html

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Demo</title>
</head>
<body><img src="{{.b64s}}"><form action="/verify" method="post"><input type="text" name="captchaId" value="{{.captchaId}}" hidden><input type="text" name="answer" value=""><input type="submit" value="Submit"></form>
</body>
</html>