SpringBoot 整合JWT获取Token令牌

前言

简单JWT入门案例

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项目目录结构如下：

一、JWT是什么？

JWT(json web token) 是为了在网络应用环境间传递声明而执行的一种基于JSON的开放标准（(RFC 7519).该token被设计为紧凑且安全的，特别适用于分布式站点的单点登录（SSO）场景。

二、使用步骤

1.引入库

代码如下（示例）：

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.auth0</groupId>
            <artifactId>java-jwt</artifactId>
            <version>3.8.2</version>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
            <version>0.6.0</version>
        </dependency>
        <dependency>
            <groupId>org.thymeleaf</groupId>
            <artifactId>thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.60</version>
        </dependency>
    </dependencies>

2.先构建Utils工具类

package com.hh.userservicejwt.utils;

import com.alibaba.fastjson.JSONObject;
import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTCreator;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.interfaces.DecodedJWT;

import java.util.Calendar;
import java.util.Map;

public class JWTUtils {

    private static final String SING = "abcdefg";

    /**
     * 生成token  header.payload.sing
     */
    public static String getToken(String jsonObject){
        Calendar istance = Calendar.getInstance();
        istance.add(Calendar.DATE,1);
        JWTCreator.Builder builder = JWT.create();
        builder.withSubject(jsonObject);
        String token = builder.withExpiresAt(istance.getTime())
                .sign(Algorithm.HMAC256(SING));
        return token;
    }

    /**
     * 验证token 验证合法性  并返回值
     */
    public static DecodedJWT verify(String token){
        return JWT.require(Algorithm.HMAC256(SING)).build().verify(token);
    }

    /**
     * 获取token信息  可以由验证的方法代替（可以不写）
     */
    public static DecodedJWT getTokenInfo(String token){
        DecodedJWT verify = JWT.require(Algorithm.HMAC256(SING)).build().verify(token);
        return verify;
    }

}

3.在构建config配置

package com.hh.userservicejwt.config;

import com.hh.userservicejwt.interceptor.JWTInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class InterceptorConfig implements WebMvcConfigurer {

    @Override
    public void addInterceptors(InterceptorRegistry registry) {

        registry.addInterceptor(new JWTInterceptor())
                .addPathPatterns("/getData")
                .excludePathPatterns("/toLogin");
    }
}

4.在创建过滤器用来检验Token令牌。

package com.hh.userservicejwt.interceptor;

import com.auth0.jwt.exceptions.AlgorithmMismatchException;
import com.auth0.jwt.exceptions.SignatureVerificationException;
import com.auth0.jwt.exceptions.TokenExpiredException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.hh.userservicejwt.utils.JWTUtils;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.HashMap;
import java.util.Map;

public class JWTInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        Map<String,Object> map = new HashMap<>();
        String token = request.getHeader("token");//获取请求头中的令牌
        try{
            JWTUtils.verify(token);
            return true;
        }catch (SignatureVerificationException e){
            e.printStackTrace();
            map.put("msg","无效签名！");
        }catch (TokenExpiredException e){
            e.printStackTrace();
            map.put("msg","token过期！");
        }catch (AlgorithmMismatchException e){
            e.printStackTrace();
            map.put("msg","token算法不一致！");
        } catch (Exception e){
            e.printStackTrace();
            map.put("msg","token无效！");
        }
        map.put("state",false);//设置状态
        //将map  转换json jackson
        String json = new ObjectMapper().writeValueAsString(map);
        response.setContentType("application/json;charset=UTF-8");
        response.getWriter().println(json);
        return false;
    }
}

5.创建Controller中的数据

package com.hh.userservicejwt.controller;

import com.alibaba.fastjson.JSONObject;
import com.auth0.jwt.interfaces.DecodedJWT;
import com.hh.userservicejwt.utils.JWTUtils;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Controller
public class UserController {


    @RequestMapping("/login")
    public String login() {
        return "login";
    }

    @RequestMapping("/toLogin")
    public String toLogin(HttpServletRequest request, HttpServletResponse response,
                          @RequestParam("username") String username, @RequestParam("password") String password) {
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("username",username);
        jsonObject.put("password",password);
        try {
            String token = JWTUtils.getToken(jsonObject.toJSONString());
            response.setHeader("token",token);
            request.setAttribute("token",token);
            return "success";
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    @RequestMapping("/getData")
    @ResponseBody
    public String getData(@RequestHeader("token") String token) {
        DecodedJWT tokenInfo = JWTUtils.getTokenInfo(token);
        String subject = tokenInfo.getSubject();
        return subject;
    }

}

6.创建html登录页面

<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>登录title>
head>
<body>
<form action="/toLogin">
    <div>
        <input type="text" name="username" placeholder="请输入账号" />
        <input type="password" name="password" placeholder="请输入密码" />
    div>
    <div>
        <input type="submit" name="提交" />
        <input type="reset" name="重置">
    div>
form>
<script th:src="@{/jquery-3.1.1.min.js}">script>
<script>



script>
body>
html>

7.登录成功后，获取Token令牌，并且下次请求的时候带上令牌，放到请求头中，并去获取资源。

<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>登录成功title>
head>
<div>
    登录成功
div>
<div>
    <button onclick="getInfo();">获取当前用户信息button>
div>
<div id="userInfo">

div>
<body>
<input type="hidden" id="token" name="token" th:value="${token}">
<script th:src="@{/jquery-3.1.1.min.js}">script>
<script th:src="@{/layui/layui.js}">script>
<script th:src="@{/loadingAjax.js}">script>
<script>

    var token = $("#token").val();

    var form;
    layui.use(['form', 'upload', 'laydate'], function () {
        form = layui.form;

        console.log(token);

    });

    function getInfo() {
        $.ajax({
            url:"/getData"
            , method: "get"
            , headers: {"token":token}
            , success: function (data) {
                $("#userInfo").html(data);
            }
        })

    }



script>
body>
html>

大致如此，谢谢大家。

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