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node.js+captchapng+jsonwebtoken实现登录验证示例

时间：2020-04-04 18:44 编辑：来源：阅读：
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摘要：node.js+captchapng+jsonwebtoken实现登录验证示例

提到登录验证，大家肯定能想到的就是12306的验证码了吧。12306为了防止刷票，可以说是煞费苦心，验证码也越来越难识别，最终即使是人也可能识别不了了。今天，小编就给大家说一下node如何实现图片验证码，以及使用token验证登录。学习本文你将学到： 1.使用captchapng生成图片验证码 2.使用jsonwebtoken实现登录验证 [b]一、图片验证码生成（最后有全部代码）[/b] 首先，我们理一下流程，第一步服务器要随机生成一组四位数。第二步，将这四位数用canvas绘图生成图片。第三步，我们要将这四位数存起来，以便用户返回数据时做对比。那么存到哪里呢？很明显为了区分用户，存到session最为稳妥。第一步，先要有一个登录页面。在这里我们依然用react, login.tsx

import * as React from 'react'
import * as ReactDom from 'react-dom'
import {Link, browserHistory} from 'react-router';
import * as axios from 'axios';
export default class Login extends React.Component<any,any>{
  constructor(props){
    super(props)
    this.state = {
      userName : '',
      password : '',
      yzNoId  : '',
      hash : Math.random()
    }
  }
  handleUserName(e) : any {
    this.setState({
      userName : e.target.value
    })
  }
  handlePassword(e) : any {
    this.setState({
      password : e.target.value
    })
  }
  handleYzId(e) : any {
    this.setState({
      yzNoId : e.target.value
    })
  }
  render(){
    const { userName, password, yzNoId } = this.state;
    return(
      <div>
        <div className="nav-wrap">
          <ul className="nav">
            <li><Link to="/home">首页</Link></li>
            <li><Link to="/imgLoad">上传</Link></li>
            <li><Link to="/login">登陆</Link></li>
          </ul>
        </div>
        <div className="content">
          <div className="login-warp">
            <p>
              <input type="text" className="username" value={userName} onChange={this.handleUserName.bind(this)} placeholder="用户名"/>
            </p>
            <p>
              <input type="text" className="password" value={password} onChange={this.handlePassword.bind(this)} placeholder="密码"/>  
            </p>  
            <p>
              <input type="text" className="yz" value={yzNoId} onChange={this.handleYzId.bind(this)} placeholder="验证码"/>
              <img src={"http://localhost:3000/captcha"} className="yz-img" />  
            </p>
            <p>
              <input type="button" className="submit" value="登陆" onClick={this.sbumit.bind(this,{userName:userName,password:password,captcha:yzNoId})} /> 
            </p>  
          </div>
        </div>
      </div>
    )
  }
}

页面是这样的 [img]http://files.jb51.net/file_images/article/201708/2017817114004756.png?2017717114018[/img] 我们需要通过服务器给一张验证图片。 router/index.js 添加如下代码

var Login = require('./controller/login');
var login = new Login;
router.get('/captcha', login.captcha);
router.post('/login',login.loginer);
login是定义在控制器的一个类的实例，captcha，loginer是它的方法。分别是返回验证图片、登录验证。
controller/login.js

var rf = require('fs');
var captchapng = require('captchapng');
class Login {
  constructor(){}
  captcha(req, res, next) {
    var str = parseInt(Math.random()*9000+1000);  //随机生成数字
    req.session.captcha = str;  // 存入session
    var p = new captchapng(80, 30, str); //生成图片
    p.color(0, 0, 0, 0);
    p.color(80, 80, 80, 255);
    var img = p.getBase64();
    var imgbase64 = new Buffer(img, 'base64');
    res.writeHead(200, {
      'Content-Type': 'image/png'
    });
    res.end(imgbase64);
  }
  loginer(req, res, next) {
    let captcha = req.body.captcha;
    let userName = req.body.userName;
    let password = req.body.password;
    if (captcha != req.session.captcha) {
      res.status(400).send({
        message: '验证码错误'
      });
    }else if(userName == "chenxuehui" && password == "123321"){
      res.json({"code":100,"verson":true,"msg":"登陆成功","token":token});
    }else{
      res.json({"code":0,"verson":false,"msg":"密码错误"});
    }
  }
}
module.exports = Login

captcha方法是生成一张含四位数字的图片，然后将图片保存到session中。将此方法在 router/index.js 中引用

router.get('/captcha', login.captcha);

也就是说我们访问localhost:3000/captcha就会返回一张图片。 [img]http://files.jb51.net/file_images/article/201708/2017817114056275.png?2017717114118[/img] 有了这个连接后我们就可以通过图片的src属性拿到该图片，但是当点击图片的时候要重新刷新，所以我们需要给图片添加一个点击刷新事件。将下面代码插入到login.tsx中

setHash() {
    this.setState({
      hash : Math.random()
    })
}

img标签也变成了

[url=http://localhost:3000/captcha?aaa="+this.state.hash]http://localhost:3000/captcha?aaa="+this.state.hash[/url]} className="yz-img" onClick={this.setHash.bind(this)} />

此时login.tsx全部代码：

import * as React from 'react'
import * as ReactDom from 'react-dom'
import {Link, browserHistory} from 'react-router';
import * as axios from 'axios';
export default class Login extends React.Component<any,any>{
  constructor(props){
    super(props)
    this.state = {
      userName : '',
      password : '',
      yzNoId  : '',
      hash : Math.random()
    }
  }
  public async sbumit(params : any) : Promise<any>{
    let res = await axios.post('http://localhost:3000/login',params);
  }
  handleUserName(e) : any {
    this.setState({
      userName : e.target.value
    })
  }
  handlePassword(e) : any {
    this.setState({
      password : e.target.value
    })
  }
  handleYzId(e) : any {
    this.setState({
      yzNoId : e.target.value
    })
  }
  setHash() {
    this.setState({
      hash : Math.random()
    })
  }
  render(){
    const { userName, password, yzNoId } = this.state;
    return(
      <div>
        <div className="nav-wrap">
          <ul className="nav">
            <li><Link to="/home">首页</Link></li>
            <li><Link to="/imgLoad">上传</Link></li>
            <li><Link to="/login">登陆</Link></li>
          </ul>
        </div>
        <div className="content">
          <div className="login-warp">
            <p>
              <input type="text" className="username" value={userName} onChange={this.handleUserName.bind(this)} placeholder="用户名"/>
            </p>
            <p>
              <input type="text" className="password" value={password} onChange={this.handlePassword.bind(this)} placeholder="密码"/>  
            </p>  
            <p>
              <input type="text" className="yz" value={yzNoId} onChange={this.handleYzId.bind(this)} placeholder="验证码"/>
              <img src={"http://localhost:3000/captcha?aaa="+this.state.hash} className="yz-img" onClick={this.setHash.bind(this)} />  
            </p>
            <p>
              <input type="button" className="submit" value="登陆" onClick={this.sbumit.bind(this,{userName:userName,password:password,captcha:yzNoId})} /> 
            </p>  
          </div>
        </div>
      </div>
    )
  }
}

这样只要点击img，就会随机生成一个hash，然后就会调用新的图片出来。接着我们进行登录验证。 loginer方法就是进行登录验证的。拿到用户的用户名信息，密码以及验证码一次对比，最后返回登录是否成功数据。当用户登陆成功以后，下次登录就不需要再次登录了，以往的方法可以选则session或者cookie的方式，在这里我们使用token。因为现在已经实现了前后端分离开发，我们更倾向于构建单页面配合ajax构建应用。而token最适合这种开发模式不过了。 [b]token登录验证[/b] token是一串经过加密的字符串，登录成功以后返回给用户保存，然后用户在请求接口时，都带这个token。所以我们需要对token进行加密。 Json Web Token就是专门解决这个问题的，原理就不做详解了，其实就是按照一定的方式得到一个字符串，然后在通过某种方式解开。我们要做的第一步就是当用户登录成功后，创建一个token返回给用户。第二步：用户拿到token后应该把token存到本地。第三步：需要写一个中间层，每次用户请求时我们验证用户携带的token是否正确。正确返回数据，不正确返回警告。用户每次请求数据的时候要在header里把token带上。第一步：还是controller/login.js

var rf = require('fs');
var jwt = require('jsonwebtoken');
var captchapng = require('captchapng');
var Tokens = require('../middleware/token')
var t = new Tokens;
class Login {
  constructor(){}
  captcha(req, res, next) {
    var str = parseInt(Math.random()*9000+1000);  //随机生成数字
    req.session.captcha = str;  // 存入session
    var p = new captchapng(80, 30, str); //生成图片
    p.color(0, 0, 0, 0);
    p.color(80, 80, 80, 255);
    var img = p.getBase64();
    var imgbase64 = new Buffer(img, 'base64');
    res.writeHead(200, {
      'Content-Type': 'image/png'
    });
    res.end(imgbase64);
  }
  loginer(req, res, next) {
    let captcha = req.body.captcha;
    let userName = req.body.userName;
    let password = req.body.password;
    if (captcha != req.session.captcha) {
      res.status(400).send({
        message: '验证码错误'
      });
    }else if(userName == "chenxuehui" && password == "123321"){
      // 设置token
      var datas = {userName:"chenxuehui"}
        //调用../middleware/token 下方法设置
      var token = t.setToken('cxh',300,datas)
      res.json({"code":100,"verson":true,"msg":"登陆成功","token":token});
    }else{
      res.json({"code":0,"verson":false,"msg":"密码错误"});
    }
  }
}

module.exports = Login

这次在loginer方法里面我们加入设置token，并返回给用户。setToken方法是设置token的方法。第二步：用户拿到后保存。在login.tsx就变成如下

import * as React from 'react'
import * as ReactDom from 'react-dom'
import {Link, browserHistory} from 'react-router';
import * as axios from 'axios';
export default class Login extends React.Component<any,any>{
  constructor(props){
    super(props)
    this.state = {
      userName : '',
      password : '',
      yzNoId  : '',
      hash : Math.random()
    }
  }
  public async sbumit(params : any) : Promise<any>{
    let res = await axios.post('http://localhost:3000/login',params);
    if(res.data.verson){
      sessionStorage.setItem('token',res.data.token);
      browserHistory.push("/home")
    }
  }
  handleUserName(e) : any {
    this.setState({
      userName : e.target.value
    })
  }
  handlePassword(e) : any {
    this.setState({
      password : e.target.value
    })
  }
  handleYzId(e) : any {
    this.setState({
      yzNoId : e.target.value
    })
  }
  setHash() {
    this.setState({
      hash : Math.random()
    })
  }
  render(){
    const { userName, password, yzNoId } = this.state;
    return(
      <div>
        <div className="nav-wrap">
          <ul className="nav">
            <li><Link to="/home">首页</Link></li>
            <li><Link to="/imgLoad">上传</Link></li>
            <li><Link to="/login">登陆</Link></li>
          </ul>
        </div>
        <div className="content">
          <div className="login-warp">
            <p>
              <input type="text" className="username" value={userName} onChange={this.handleUserName.bind(this)} placeholder="用户名"/>
            </p>
            <p>
              <input type="text" className="password" value={password} onChange={this.handlePassword.bind(this)} placeholder="密码"/>  
            </p>  
            <p>
              <input type="text" className="yz" value={yzNoId} onChange={this.handleYzId.bind(this)} placeholder="验证码"/>
              <img src={"http://localhost:3000/captcha?aaa="+this.state.hash} className="yz-img" onClick={this.setHash.bind(this)} />  
            </p>
            <p>
              <input type="button" className="submit" value="登陆" onClick={this.sbumit.bind(this,{userName:userName,password:password,captcha:yzNoId})} /> 
            </p>  
          </div>
        </div>
      </div>
    )
  }
}

在sbumit方法里我们将token放到了sessonstorage里面。第三步：设置中间件每次请求接口时，验证token,如果解析成功加入到请求头里面。 ./middleware/token.js

var jwt = require('jsonwebtoken');
class Tokens {
  constructor(){}
  testToken(req,res,next) {
    var token = req.body.token || req.query.token || req.headers['x-access-token'];
       
    if(token) {
            //存在token，解析token
      jwt.verify(token, 'cxh' , function(err,decoded) {
        if(err) {
                   // 解析失败直接返回失败警告
          return res.json({success:false,msg:'token错误'})
        }else {
                   //解析成功加入请求信息，继续调用后面方法
          req.userInfo = decoded;
          next()
        }
      })
    }else {
      return res.status(403).send({success:false,msg:"没有token"})
    }
  }
  setToken(name,time,data) {
    var jwtSecret = name;
    var token = jwt.sign(data, jwtSecret, {
      expiresIn: time
    })
    return token;
  }
}
module.exports = Tokens

testToken方法是验证token，setToken是设置token方法假如没有登录请求是这样的 [img]http://files.jb51.net/file_images/article/201708/2017817114254424.png?201771711437[/img] 在 router/index.js

var express = require('express');
var router = express.Router();
var rf = require('fs');
var Login = require('./controller/login');
var Tokens = require('./middleware/token')
var t = new Tokens;
var login = new Login;
//主页
router.get('/', function(req, res, next) {
  res.render("wap/index")
});
//获取图片验证码
router.get('/captcha', login.captcha);
//登录验证
router.post('/login',login.loginer);
//请求数据时 t.testToken 验证token
router.post('/list',t.testToken,function(req, res, next){
  res.json({
    //在请求信息里面拿到数据
    username : req.userInfo.userName,
    success : true,
    result : [
      {
        name:'1111111'
      },
      {
        name :'22222'
      }
    ]
  })
})
module.exports = router;

我们在另一个页面调用list接口试一下

import * as axios from 'axios';
import { transToken } from '../decorator/index'


class Home extends React.Component<any,any>{
  constructor(props){
    super(props)
    this.state = {
      data : ''
    }
  }
  async getList(): Promise<any>{
    let token = sessionStorage.getItem('token');
    const config = {
     // 请求头信息
     headers: {'x-access-token': token}      
    }
    let res = await axios.post('http://localhost:3000/list',{},config);
    if(!res.data.success){
      browserHistory.push('/login');
      return;
    }
    this.setState({
      data : res.data
    })
  }
  render(){
    const { data } = this.state;
    return(
      <div>
        <div className="nav-wrap">
          <ul className="nav">
            <li><Link to="/home">首页</Link></li>
            <li><Link to="/imgLoad">上传</Link></li>
            <li><Link to="/login">登陆</Link></li>
          </ul>
        </div>
        <div className="content">
          Home
          <span onClick={this.getList.bind(this)}>获取数据</span>
          <div>{
            data ? data.result.map( (val,k) => {
              return <li key = {k}>{val.name}</li>
            }) : null
          }</div>
        </div>
      </div>
      
    )
  }
}
export default Home

当调用getList时，如果此时没有登录res.data.success就会为false，则跳到登录页。 [b]全部代码[/b] node.js app.js

var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var session = require("express-session");
var ejs = require('ejs');

var index = require('./routes/index');


var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
// app.set('view engine', 'jade');
app.engine('html', ejs.__express);
app.set('view engine', 'html');
app.use(session({
  secret:"dabao",
  resave:false,
  saveUninitialized:true,
  cookie:{}
}));
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser({limit: 5000000}));
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, '')));

app.use('/', index);


// catch 404 and forward to error handler
app.use(function(req, res, next) {
 var err = new Error('Not Found');
 err.status = 404;
 next(err);
});

// error handler
app.use(function(err, req, res, next) {
 // set locals, only providing error in development
 res.locals.message = err.message;
 res.locals.error = req.app.get('env') === 'development' ? err : {};

 // render the error page
 res.status(err.status || 500);
 res.render('error');
});

module.exports = app;

index.js

var express = require('express');
var router = express.Router();
var rf = require('fs');
var Login = require('./controller/login');
var Tokens = require('./middleware/token')
var t = new Tokens;
var login = new Login;
/* GET home page. */
router.get('/', function(req, res, next) {
  res.render("wap/index")
});
router.post('/upLoadImg',function(req,res,next){
  let imgData = req.body.imgData;
  console.log(imgData)
  let base64Data = imgData.replace(/^data:image\/\w+;base64,/, "");
  let dataBuffer = new Buffer(base64Data, 'base64');
  let timer = Number( new Date() );
  console.log(timer)
  rf.writeFile("views/images/artCover"+timer+".png",dataBuffer, function(err) {
    if(err) {
     res.json({"code":400,"verson":false,"msg":err});
    }else {
     res.json({"code":100,"verson":true,"url":"views/src/common/images/artCover/"+timer+".png"});
    }
  });
})
router.get('/captcha', login.captcha);
router.post('/login',login.loginer);
router.post('/list',t.testToken,function(req, res, next){
  // 先解析token 
  console.log(req.userInfo)
  res.json({
    username : req.userInfo.userName,
    success : true,
    result : [
      {
        name:'1111111'
      },
      {
        name :'22222'
      }
    ]
  })
})
module.exports = router;

controller/login.js

var rf = require('fs');
var jwt = require('jsonwebtoken');
var captchapng = require('captchapng');
var Tokens = require('../middleware/token')
var t = new Tokens;
class Login {
  constructor(){}
  captcha(req, res, next) {
    var str = parseInt(Math.random()*9000+1000);  //随机生成数字
    req.session.captcha = str;  // 存入session
    var p = new captchapng(80, 30, str); //生成图片
    p.color(0, 0, 0, 0);
    p.color(80, 80, 80, 255);
    var img = p.getBase64();
    var imgbase64 = new Buffer(img, 'base64');
    res.writeHead(200, {
      'Content-Type': 'image/png'
    });
    res.end(imgbase64);
  }
  loginer(req, res, next) {
    let captcha = req.body.captcha;
    let userName = req.body.userName;
    let password = req.body.password;
    if (captcha != req.session.captcha) {
      res.status(400).send({
        message: '验证码错误'
      });
    }else if(userName == "chenxuehui" && password == "123321"){
      // 设置token
      var datas = {userName:"chenxuehui"}
      var token = t.setToken('cxh',300,datas)
      res.json({"code":100,"verson":true,"msg":"登陆成功","token":token});
    }else{
      res.json({"code":0,"verson":false,"msg":"密码错误"});
    }
  }
}
module.exports = Login

middleware/token.js

var jwt = require('jsonwebtoken');

class Tokens {
  constructor(){}
  testToken(req,res,next) {
    var token = req.body.token || req.query.token || req.headers['x-access-token'];

    if(token) {
      jwt.verify(token, 'cxh' , function(err,decoded) {
        if(err) {
          return res.json({success:false,msg:'token错误'})
        }else {
          req.userInfo = decoded;
          next()
        }
      })
    }else {
      return res.status(403).send({success:false,msg:"没有token"})
    }
  }
  setToken(name,time,data) {
    var jwtSecret = name;
    var token = jwt.sign(data, jwtSecret, {
      expiresIn: time
    })
    return token;
  }
}
module.exports = Tokens

react部分 login.tsx

import * as React from 'react'
import * as ReactDom from 'react-dom'
import {Link, browserHistory} from 'react-router';
import * as axios from 'axios';
export default class Login extends React.Component<any,any>{
  constructor(props){
    super(props)
    this.state = {
      userName : '',
      password : '',
      yzNoId  : '',
      hash : Math.random()
    }
  }
  public async sbumit(params : any) : Promise<any>{
    let res = await axios.post('http://localhost:3000/login',params);
    if(res.data.verson){
      sessionStorage.setItem('token',res.data.token);
      browserHistory.push("/home")
    }
  }
  handleUserName(e) : any {
    this.setState({
      userName : e.target.value
    })
  }
  handlePassword(e) : any {
    this.setState({
      password : e.target.value
    })
  }
  handleYzId(e) : any {
    this.setState({
      yzNoId : e.target.value
    })
  }
  setHash() {
    this.setState({
      hash : Math.random()
    })
  }
  render(){
    const { userName, password, yzNoId } = this.state;
    return(
      <div>
        <div className="nav-wrap">
          <ul className="nav">
            <li><Link to="/home">首页</Link></li>
            <li><Link to="/imgLoad">上传</Link></li>
            <li><Link to="/login">登陆</Link></li>
          </ul>
        </div>
        <div className="content">
          <div className="login-warp">
            <p>
              <input type="text" className="username" value={userName} onChange={this.handleUserName.bind(this)} placeholder="用户名"/>
            </p>
            <p>
              <input type="text" className="password" value={password} onChange={this.handlePassword.bind(this)} placeholder="密码"/>  
            </p>  
            <p>
              <input type="text" className="yz" value={yzNoId} onChange={this.handleYzId.bind(this)} placeholder="验证码"/>
              <img src={"http://localhost:3000/captcha?aaa="+this.state.hash} className="yz-img" onClick={this.setHash.bind(this)} />  
            </p>
            <p>
              <input type="button" className="submit" value="登陆" onClick={this.sbumit.bind(this,{userName:userName,password:password,captcha:yzNoId})} /> 
            </p>  
          </div>
        </div>
      </div>
    )
  }
}

home.js 获取列表信息

import * as React from 'react'
import * as ReactDom from 'react-dom'
import {Link, browserHistory} from 'react-router';
import * as axios from 'axios';
class Home extends React.Component<any,any>{
  constructor(props){
    super(props)
    this.state = {
      data : ''
    }
  }
  async getList(): Promise<any>{
    let token = sessionStorage.getItem('token');
    const config = {
     // 请求头信息
     headers: {'x-access-token': token}      
    }
    let res = await axios.post('http://localhost:3000/list',{},config);
    if(!res.data.success){
      browserHistory.push('/login');
      return;
    }
    this.setState({
      data : res.data
    })
  }
  render(){
    const { data } = this.state;
    return(
      <div>
        <div className="nav-wrap">
          <ul className="nav">
            <li><Link to="/home">首页</Link></li>
            <li><Link to="/imgLoad">上传</Link></li>
            <li><Link to="/login">登陆</Link></li>
          </ul>
        </div>
        <div className="content">
          Home
          <span onClick={this.getList.bind(this)}>获取数据</span>
          <div>{
            data ? data.result.map( (val,k) => {
              return <li key = {k}>{val.name}</li>
            }) : null
          }</div>
        </div>
      </div>
      
    )
  }
}
export default Home

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程素材网。

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