问题引入:

在springboot 项目写了个定时任务,里面有段代码通过Feign 调用远程服务,发现通过接口调用可以程序正常执行, 通过配置定时任务发现定时任务没执行,看日志是报了NP.

问题跟踪:

写了个demo 重现以上错误:

@Api(tags = "XXX控制器")
@RestController
@RequestMapping("/tenderBid")
@Slf4j
public class TenderBidController extends JeecgController<Tender, ITenderService> {

    @Autowired
    private IdeliverRemoteService ideliverRemoteService;

    @Autowired
    private ITenderBidDetailService tenderBidDetailService;

//    final IdeliverRemoteService ideliverRemoteService;
//
//    public TenderBidController(IdeliverRemoteService ideliverRemoteService) {
//        this.ideliverRemoteService = ideliverRemoteService;
//    }

    /**
     * @return java.lang.String
     * @Title: 测试定时任务, 每6秒执行一次(注意方法不能带参数)
     * @Author: ken
     * @Description:
     * @Date: 2023/2/20  17:01
     * @Param: []
     **/
    @Scheduled(cron ="*/6 * * * * ?")
    @RequestMapping(value = "/testTask", method = RequestMethod.POST)
    public void testTask() {
        log.info("now is:{}", LocalDateTime.now().toString());
        com.alibaba.fastjson2.JSONObject vo = new com.alibaba.fastjson2.JSONObject();
        vo.put("sign", "8145e202-d8b5-f613-5e24-50bda4bbd75c");
        //IdeliverRemoteService ideliverRemoteService = (IdeliverRemoteService) SpringContextUtils.getBean("ideliver-service");
        //IdeliverRemoteService ideliverRemoteService = (IdeliverRemoteService)AppContextUtil.getBean("ideliver-service");
        //IdeliverRemoteService ideliverRemoteService = AppContextUtil.getFeignBean("ideliver-service", IdeliverRemoteService.class);
        log.info("TenderController --> ideliverRemoteService:{}", ideliverRemoteService);

        try {

            com.alibaba.fastjson2.JSONObject result = ideliverRemoteService.getSolutionKeyWord(vo);
            log.info("TenderController --> testTask result: {}", JSONObject.toJSONString(result));
        } catch (Exception e) {
            log.error("TenderController --> testTask error：{}", e.getMessage(), e);
        }

    }

注入的Feign

@Service
@FeignClient(name = "ideliver-service", url = "${service.ideliver.url:}", configuration = IdeliverFeignConfig.class)
public interface IdeliverRemoteService {
    /**
     * @Title: 查询解决方案对应的关键词
     * @Author: ken
     * @Description:
     * @Date: 2023/2/22  16:10
     * @Param: [vo]
     * @return com.alibaba.fastjson2.JSONObject
     **/
    @PostMapping(value = "${service.ideliver.api.SolutionKeyWord:/ideliver/SolutionKeyWord}")
    JSONObject getSolutionKeyWord(@RequestBody(required=false) JSONObject vo);
}

通过日志发现是获取到了 ideliverRemoteService的值:
ideliverRemoteService:HardCodedTarget(type=IdeliverRemoteService, name=ideliver-service, url=https://ideliver.xxx.ltd)

跟踪代码,在 IdeliverFeignConfig 类找到原因,其中有段代码从前端获取Cookie 未判断空,导致报错:

    @Bean
    public RequestInterceptor requestInterceptor() {
        return requestTemplate -> {
            RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
            HttpServletRequest request = ((ServletRequestAttributes) requestAttributes).getRequest();
            // 2.从request对象中获取cookie
            String cookies = request.getHeader("Cookie");
            requestTemplate.header("Cookie", cookies);
        };
    }

代码加非空判断,问题解决:

    @Bean
    public RequestInterceptor requestInterceptor() {
        return requestTemplate -> {
            RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
            if(Objects.isNull(requestAttributes)){
                return;
            }
            HttpServletRequest request = ((ServletRequestAttributes) requestAttributes).getRequest();
            // 2.从request对象中获取cookie
            String cookies = request.getHeader("Cookie");
            requestTemplate.header("Cookie", cookies);
        };
    }

问题结论:

程序报错一定要认真定位为题, 不能自以为, 开始以为是没有注入进来, 最后debug 定位解决为题. 还有一点对于一些地方,如果远程调用,异常捕获和日志打印是非常必要的,不然很难定位到问题. 可以通过如下写法轻易打印出日志:
**log.error("TenderController --> testTask error：{}", e.getMessage(), e);**

问题补充:

关于 FeignClient 的注入问题, 经测试是第一种和第四种可以注入, 第二种和第三种是无法注入的,大家有空可以试验下:
在这里插入图片描述

/**
 * @Title: 配置类，解决定时任务无法注入的问题
 * @Author: ken
 * @Description:
 * @Date: 2023/3/6  16:02
 **/
@Component
public class AppContextUtil implements ApplicationContextAware {

    private static ApplicationContext applicationContext;

    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }


    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        AppContextUtil.applicationContext = applicationContext;

    }


    public static Object getBean(String beanName) {
        return applicationContext.getBean(beanName);

    }

    public static <T> T getFeignBean(String beanName, Class<T> tClass) {
        //我这边主要在gateway用到这两行代码
        FeignContext feignContext = applicationContext.getBean("feignContext", FeignContext.class);
        return feignContext.getInstance(beanName, tClass);
    }
}