Golang使用验证码

怼烎@ 2022-10-08 05:50 319阅读 0赞

使用的第三方库

go get github.com/dchest/captcha

package main
    
    import (
    	"fmt"
    	"github.com/dchest/captcha"
    	"io"
    	"log"
    	"net/http"
    	"text/template"
    )
    
    var formTemplate = template.Must(template.New("example").Parse(formTemplateSrc))
    
    func showFormHandler(w http.ResponseWriter, r *http.Request) { 
    	d := struct { 
    		CaptchaId string
    	}{ 
    		captcha.New(),
    	}
    	if err := formTemplate.Execute(w, &d); err != nil { 
    		// 处理错误，500 服务器异常
    		http.Error(w, err.Error(), http.StatusInternalServerError)
    	}
    }
    
    func processFormHandler(w http.ResponseWriter, r *http.Request) { 
    	w.Header().Set("Content-Type", "text/html; charset=utf-8")
    	// VerifyString方法用来验证并删除验证码，因为验证之后验证码就没存在的意义了
    	// captchaId是标识验证码的ID，captchaSolution是客户输入的数字
    	if !captcha.VerifyString(r.FormValue("captchaId"), r.FormValue("captchaSolution")) { 
    		io.WriteString(w, "错误的验证码解决方案!不允许机器人!\n")
    	} else { 
    		io.WriteString(w, "伟大的人类!你破解了验证码。\n")
    	}
    	io.WriteString(w, "<br><a href='/'>再试一次</a>")
    }
    
    func main() { 
    	http.HandleFunc("/", showFormHandler)  // 验证码主页面
    	http.HandleFunc("/process", processFormHandler)  // 验证客户端发送过来的验证码是否正确
    	http.Handle("/captcha/", captcha.Server(captcha.StdWidth, captcha.StdHeight))  // 图像的生成，并返回图片
    	fmt.Println("服务运行于： http://localhost:8666")
    	if err := http.ListenAndServe("localhost:8666", nil); err != nil { 
    		log.Fatal(err)
    	}
    }
    
    const formTemplateSrc = ` <!doctype html> <head><title>验证码</title></head> <body> <script> function reload() { setSrcQuery(document.getElementById('image'), "reload=" + (new Date()).getTime()); return false; } </script> <form action="/process" method=post> <p>输入你在下面的图片中看到的数字:</p> <p><img id=image src="/captcha/{ {.CaptchaId}}.png" alt="Captcha image"></p> <input type=hidden name=captchaId value="{ {.CaptchaId}}"><br> <input name=captchaSolution> <input type=submit value=提交> </form> `

运行后访问页面：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzMjc5NDU3_size_16_color_FFFFFF_t_70]  
输入正确后跳转：  
![在这里插入图片描述][20210620175408364.png]  
输入错误后跳转：  
![在这里插入图片描述][20210620175522305.png]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzMjc5NDU3_size_16_color_FFFFFF_t_70]: /images/20221005/151423e3ab1f42e386ab331982cf7dfa.png
[20210620175408364.png]: /images/20221005/59f1b348c9cc42ae9ddf596d19bd79ee.png
[20210620175522305.png]: /images/20221005/0963481a847a45ca835766196afa932f.png