登陆 数据库查找 以及redis校验验证码

Posted 2022-09-29 p-123

```
//用于生成验证ma
const svgCaptcha = require("svg-captcha") 

//mysql  用于在数据库中查找前端输入的用户名和密码
const mysql = require(‘mysql‘);

const connection = mysql.createConnection(
  host: ‘localhost‘,
  user: ‘root‘,
  password: ‘12345678‘,
  database: ‘sys‘
);

connection.connect();

//redis数据库用于存储随机生成的验证码
//便于及时更新

const client = redis.createClient();

//redis 如果没有启动redis，会报错
//redis 启动命令 redis-server
//新建terminal 输入redis-cli

client.on("error", function (err) 
  console.log("Trror" + err);
)

//生成token  方便redis存储和替换
function getID(length) 
  return Number(Math.random().toString().substr(3, length) + Date.now()).toString(36);



  //验证码 
 app.get("/cap", (req, res) => 
   const cap = svgCaptcha.create();
   //cap=>data:...,text:jsoa
   //text:随机生成的四位验证码
   //data:传递给前端的验证码的图片
   
   
   let text = cap.text;
   res.type("svg");
   
   //生成一个ID redis保存 并传递给前端
   let captchaId = getID(10)
   client.set(captchaId, text)
   res.send(
     cap,
     captchaId
   )
   return
 )

  //前端引用图片
 //  <span dangerouslySetInnerhtml= __html: captcha  onClick=() => this.getcaptcha()></span>
 
 
 
 //登陆      
app.post("/getlogin", async (req, res) => 
   let  username, password, verification, captchaId  = req.body;
        let redisCaptcha = await new Promise((resolve) => 
          client.get(captchaId, function (err, res) 
            return resolve(res)
          )
        )

        if (verification === redisCaptcha) 
         else 
          res.send(
            code: 0,
            message: "验证码错误或过期"
          )
          return
        

     //数据库中查找数据
      connection.query(`SELECT * FROM table where username=‘$username‘ &&passwrd=‘$password‘`, function (error, results, fields) 
          if (error) throw error;
          if (results[0]) 
            res.send( code: 1, message: "登陆成功" )
           else 
            res.send( code: 0, message: "用户名或密码错误" )
            return
          
        );

      )
```