SpringBoot从入门到精通（三十四）如何集成JWT实现Token验证

<dependency>
    <groupId>com.auth0</groupId>
    <artifactId>java-jwt</artifactId>
    <version>3.10.3</version>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

@Component
public class TokenUtil {
    @Value("${token.secretKey}")
    private String secretKey;
    /**
     * 加密token.
     */
    public String getToken(String userId, String userRole) {
        //这个是放到负载payLoad 里面,魔法值可以使用常量类进行封装.
        String token = JWT
                .create()
                .withClaim("userId" ,userId)
                .withClaim("userRole", userRole)
                .withClaim("timeStamp", System.currentTimeMillis())
                .sign(Algorithm.HMAC256(secretKey));
        return token;
    }
    /**
     * 解析token.
     * {
     * "userId": "weizhong",
     * "userRole": "ROLE_ADMIN",
     * "timeStamp": "134143214"
     * }
     */
    public Map<String, String> parseToken(String token) {
        HashMap<String, String> map = new HashMap<String, String>();
        DecodedJWT decodedjwt = JWT.require(Algorithm.HMAC256(secretKey))
                .build().verify(token);
        Claim userId = decodedjwt.getClaim("userId");
        Claim userRole = decodedjwt.getClaim("userRole");
        Claim timeStamp = decodedjwt.getClaim("timeStamp");
        map.put("userId", userId.asString());
        map.put("userRole", userRole.asString());
        map.put("timeStamp", timeStamp.asLong().toString());
        return map;
    }
}

@Slf4j
@Component
public class AuthHandlerInterceptor implements HandlerInterceptor {
    @Autowired
    TokenUtil tokenUtil;
    @Value("${token.refreshTime}")
    private Long refreshTime;
    @Value("${token.expiresTime}")
    private Long expiresTime;
    /**
     * 权限认证的拦截操作.
     */
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object object) throws Exception {
        log.info("=======进入拦截器========");
        // 如果不是映射到方法直接通过,可以访问资源.
        if (!(object instanceof HandlerMethod)) {
            return true;
        }
        //为空就返回错误
        String token = httpServletRequest.getHeader("token");
        if (null == token || "".equals(token.trim())) {
            return false;
        }
        log.info("==============token:" + token);
        Map<String, String> map = tokenUtil.parseToken(token);
        String userId = map.get("userId");
        String userRole = map.get("userRole");
        long timeOfUse = System.currentTimeMillis() - Long.parseLong(map.get("timeStamp"));
        //1.判断 token 是否过期
        if (timeOfUse < refreshTime) {
            log.info("token验证成功");
            return true;
        }
        //超过token刷新时间，刷新 token
        else if (timeOfUse >= refreshTime && timeOfUse < expiresTime) {
            httpServletResponse.setHeader("token",tokenUtil.getToken(userId,userRole));
            log.info("token刷新成功");
            return true;
        }
        //token过期就返回 token 无效.
        else {
            throw new TokenAuthExpiredException();
        }
    }
}

@Configuration
public class AuthWebMvcConfigurer implements WebMvcConfigurer {
    @Autowired
    AuthHandlerInterceptor authHandlerInterceptor;
    /**
     * 给除了 /login 的接口都配置拦截器,拦截转向到 authHandlerInterceptor
     */
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(authHandlerInterceptor)
                .addPathPatterns("/**")
                .excludePathPatterns("/login");
    }
}

@RestController
public class TokenTestController {
    @Autowired
    TokenUtil tokenUtil;
    @PostMapping("/login")
    public String login(@RequestBody LoginUser user){
        // 先验证用户的账号密码,账号密码验证通过之后，生成Token
        String role = "ROLE_ADMIN";
        String token = tokenUtil.getToken(user.username,role);
        return token;
    }
    @PostMapping("/testToken")
    public String testToken(HttpServletRequest request){
        String token = request.getHeader("token");
        tokenUtil.parseToken(token);
        return "请求成功";
    }
}