【SpringBoot拦截器】

【SpringBoot拦截器】 SpringBoot拦截器的使用

作用：每次调接口先进拦截器（如果哪些请求地址不需要拦截可以配置里加入到白名单），主要用在平台登录。

具体使用：

1. 创建我们自己的拦截器类并实现 HandlerInterceptor 接口

@Slf4j
@Component
public class AuthInterceptor implements HandlerInterceptor {

    @Autowired
    private RedisUtils redisUtils;

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest,
                             HttpServletResponse httpServletResponse,
                             Object object) {
        //之里面主要写自己的拦截逻辑

        //1.请求方式为OPTIONS直接跳过返回true
        String method = httpServletRequest.getMethod();
        if (method.equals(HttpMethod.OPTIONS.toString())) {
            return true;
        }

        //2.获取IP,打印日志 TODO 后续优化为统一工具类
        String ip = IpUtils.getIpAddress(httpServletRequest);

        //3.从请求头获取Token
        String token = httpServletRequest.getHeader("token");

        //4.Token为空直接返回false
        if (StringUtils.isBlank(token)) {
            log.error("[拦截器] token为空,请求失败 ip=[{}]", ip);
            addMessageToResponse(httpServletResponse, HttpStatus.UNAUTHORIZED);
            return false;
        }

        //5.从Redis获取登陆用户信息
        String userInfoKey = RedisKeyUtils.getUserInfoKey(token);
        SystemUserVo systemUserVo = (SystemUserVo) redisUtils.get(userInfoKey);

        //6.用户信息为空，代表登陆TOKEN已过期
        if (null == systemUserVo) {
            addMessageToResponse(httpServletResponse, HttpStatus.UNAUTHORIZED);
            log.error("[拦截器] 用户信息过期,请重新登录 ip=[{}] token=[{}]", ip, token);
            return false;
        }

        //7.重置Redis用户信息的过期时间
        redisUtils.expire(userInfoKey, RedisConstants.SYSTEM_USERINFO.getExpireTime());

        //8.设置Redis用户对应TOKEN的过期时间
        String userTokenKey = RedisKeyUtils.getUserTokenKey(systemUserVo.getLoginName());
        redisUtils.expire(userTokenKey, RedisConstants.SYSTEM_USERTOKEN.getExpireTime());

        //8.把用户名和token存入Request，方便后面的使用
        httpServletRequest.setAttribute("loginName", systemUserVo.getLoginName());
        httpServletRequest.setAttribute("userName", systemUserVo.getName());
        httpServletRequest.setAttribute("token", token);

        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest,
                           HttpServletResponse httpServletResponse,
                           Object o, ModelAndView modelAndView) {
    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest,
                                HttpServletResponse httpServletResponse,
                                Object o, Exception e) {
    }

    
    private void addMessageToResponse(HttpServletResponse response, HttpStatus httpStatus) {

        //1.设置响应异常状态
        response.setStatus(httpStatus.value());
        response.setContentType("application/json;charset=UTF-8");

        //2.响应异常信息写入
        ServletOutputStream outputStream = null;
        try {
            outputStream = response.getOutputStream();
            outputStream.write(httpStatus.getReasonPhrase().getBytes(StandardCharsets.UTF_8));
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                outputStream.flush();
                outputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

2. 创建一个Java类继承WebMvcConfigurer，并重写 addInterceptors 方法。 实例化我们自定义的拦截器，然后将对像手动添加到拦截器链中（在addInterceptors方法中添加）。

@Configuration
public class WebConfig implements WebMvcConfigurer {

    @Autowired
    private WhiteListConfig whiteListConfig;

    @Bean
    AuthInterceptor authlInterceptor() {
        return new AuthInterceptor();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //获取白名单
        List whiteListUrl = whiteListConfig.getUrl();

        registry.addInterceptor(authlInterceptor())
                .addPathPatterns("
@Component
@ConfigurationProperties(prefix = "yuffie2.white-list")
@Data
public class WhiteListConfig {

    
    private List url;
}

4. 配置白名单

# 自定义配置
yuffie2:
  # 白名单配置
  white-list:
    url:
      - /swagger-resources/**
      - /webjars/**
      - /v2/**
      - /swagger-ui.html/**
      - /api/v1/tokens