前言

前端用什么框架都可以，这里选择小巧的vuejs。

要实现的功能很简单：
1，登录功能，成功将服务器返回的令牌存在本地
2，使用带令牌的标头访问服务器的一个资源

本次实验环境：

"dependencies": {
    "vue": "^2.2.1"
  },
  "devDependencies": {
    "babel-core": "^6.0.0",
    "babel-loader": "^6.0.0",
    "babel-preset-latest": "^6.0.0",
    "cross-env": "^3.0.0",
    "css-loader": "^0.25.0",
    "file-loader": "^0.9.0",
    "vue-loader": "^11.1.4",
    "vue-template-compiler": "^2.2.1",
    "webpack": "^2.2.0",
    "webpack-dev-server": "^2.2.0"
  }

开发IDE：原子

首先建一个项目

使用webpack构建

/Atom# vue init webpack-simple vue-jwt-demo
...
/Atom# cd vue-jwt-demo/
/Atom/vue-jwt-demo# cnpm install
/Atom/vue-jwt-demo# npm run dev

安装插件

/Atom/vue-jwt-demo# cnpm install vue-router

/Atom/vue-jwt-demo# cnpm install vue-resource

整体目录

auth.js

完成令牌的访问

const SERVER_URL = 'http://localhost:8081'
const LOGIN_URL = SERVER_URL+'/login2'

export default{
    data:{
        authenticated:false
    },
    login(context,info){
        context.$http.post(LOGIN_URL,info).then(function(data){
            console.log(data.bodyText)
            localStorage.setItem('token',data.bodyText);
            this.authenticated = true
            //跳到home页
            this.$router.push('home')
        },function(err){
            console.log(err+","+err.body.message)
            context.error = err.body.message
        })
    },
    getAuthHeader(){
        return {
            'Authorization':'Bearer '+localStorage.getItem('token')
        }
    },
    checkAuth(){
        var token = localStorage.getItem('token')
        if(token){
            this.authenticated = true
        }else{
            this.authenticated = false
        }
    }
}

main.js

程序入口：完成路由和初始化

import Vue from 'vue'
import App from './App.vue'
import Login from './component/Login.vue'
import Home from './component/Home.vue'
import VueRouter from 'vue-router'
import VueResource from 'vue-resource'
import auth from './auth/auth'

Vue.use(VueRouter)
Vue.use(VueResource)

//在启动APP时进行校验是否有token
auth.checkAuth()

const routes= [
    {
        path:'/',redirect:'/login'
    },
    {
        path:'/login',component:Login
    },
    {
        path:'/home',component:Home
    }
]

const router = new VueRouter({
    routes
})
new Vue({
  router,
  render: h => h(App)
}).$mount('#app')

应用程序

页面载体

<template>
  <div id="app">
    <h1>{{msg}}</h1>
    <router-view></router-view>
  </div>
</template>

<script>
export default {
  name: 'app',
  data () {
    return {
      msg: 'Vue前后端分离demo'
    }
  }
}
</script>

Login.vue

登录页面

<template>
  <div>
    <h2>登录</h2>
    <p>{{ error }}</p>
    <div>
      <input
        type="text"
        placeholder="Enter your username"
        v-model="info.username"
      >
    </div>
    <div>
      <input
        type="password"
        placeholder="Enter your password"
        v-model="info.password"
      >
    </div>
    <button @click="submit()">登录</button>
  </div>
</template>

<script>
import auth from '../auth/auth'

export default {

  data() {
    return {
      info: {
        username: '',
        password: ''
      },
      error: ''
    }
  },
  methods: {
    submit() {
      var info = {
        username: this.info.username,
        password: this.info.password
      }
      auth.login(this, info)
    }
  }
}
</script>

效果：

主场

主页面，访问一个获取邮箱的请求

<template>
  <div id="home">
    <h1>{{msg}}</h1>
    <button @click="getEmail()">Get Email</button>
    <h2>Email:{{email}}</h2>
  </div>
</template>

<script>
import auth from '../auth/auth'

export default {
  name: 'home',
  data () {
    return {
      msg: '欢迎您登录成功',
      email:''
    }
    },
    beforeCreate(){
        //如果没有token的话需要重新登录
         if(!auth.authenticated){
            this.$router.push('login')
        }
    },
    methods:{
        getEmail(){
            this.$http.get('http://localhost:8081/user/getEmail',{
                headers:auth.getAuthHeader()
            }).then(function(re){
                this.email = re.bodyText
            },function(){
                console.log("get email error")
            })
        }
    }
}
</script>

<style>
#app {
  font-family: 'Avenir', Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
  color: #2c3e50;
  margin-top: 60px;
}

h1, h2 {
  font-weight: normal;
}

a {
  color: #42b983;
}
</style>

对应在服务端：

@GetMapping("/getEmail")
    public String getEmail() {
        return "xxxx@qq.com";
    }

可看到浏览器的本地存储：

参考：
https : //github.com/auth0-blog/vue-jwt-authentication（基于vue1.x）
https://router.vuejs.org/zh-cn/essentials/getting-started.html