最近项目进入联调阶段,服务层的接口需要和协议层进行交互,协议层需要将入参 [json 字符串] 组装成服务层所需的 json 字符串,组装的过程中很容易出错。
入参出错导致接口调试失败问题在联调中出现很多次,因此就想写一个请求日志切面把入参信息打印一下,同时协议层调用服务层接口名称对不上也出现了几次,通过请求日志切面就可以知道上层是否有没有发起调用,方便前后端甩锅还能拿出证据。
本篇文章是实战性的,对于切面的原理不会讲解,只会简单介绍一下切面的知识点
面向切面编程是一种编程范式,它作为 OOP 面向对象编程的一种补充,用于处理系统中分布于各个模块的横切关注点,比如事务管理、权限控制、缓存控制、日志打印等等。
AOP 把软件的功能模块分为两个部分:核心关注点和横切关注点。业务处理的主要功能为核心关注点,而非核心、需要拓展的功能为一切关注点。AOP 的作用在于分离系统中的各种关注点,将核心关注点和横切关注点进行分离,使用切面有以下好处:
@Aspect => 声明该类为一个注解类
切点注解:
@Pointcut => 定义一个切点,可以简化代码
通知注解:
使用 @Pointcut 定义切点
@Pointcut 定义了一个切点,因为是请求日志切边,因此切点定义的是 Controller 包下的所有类下的方法。定义切点以后在通知注解中直接使用 requestServer 方法名就可以了
使用 @Before 再切点前执行
- @Before("requestServer()")
- public void doBefore(JoinPoint joinPoint) {
- ServletRequestAttributes attributes = (ServletRequestAttributes)
- RequestContextHolder.getRequestAttributes();
- HttpServletRequest request = attributes.getRequest();
-
- LOGGER.info("===============================Start========================");
- LOGGER.info("IP : {}", request.getRemoteAddr());
- LOGGER.info("URL : {}", request.getRequestURL().toString());
- LOGGER.info("HTTP Method : {}", request.getMethod());
- LOGGER.info("Class Method : {}.{}", joinPoint.getSignature().getDeclaringTypeName(), joinPoint.getSignature().getName());
- }
在进入 Controller 方法前,打印出调用方 IP、请求 URL、HTTP 请求类型、调用的方法名
使用 @Around 打印进入控制层的入参
- @Around("requestServer()")
- public Object doAround(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
- long start = System.currentTimeMillis();
- Object result = proceedingJoinPoint.proceed();
- LOGGER.info("Request Params : {}", getRequestParams(proceedingJoinPoint));
- LOGGER.info("Result : {}", result);
- LOGGER.info("Time Cost : {} ms", System.currentTimeMillis() - start);
-
- return result;
- }
打印了入参、结果以及耗时
- private Map<String, Object> getRequestParams(ProceedingJoinPoint proceedingJoinPoint) {
- Map<String, Object> requestParams = new HashMap<>();
-
- //参数名
- String[] paramNames = ((MethodSignature)proceedingJoinPoint.getSignature()).getParameterNames();
- //参数值
- Object[] paramValues = proceedingJoinPoint.getArgs();
-
- for (int i = 0; i < paramNames.length; i++) {
- Object value = paramValues[i];
-
- //如果是文件对象
- if (value instanceof MultipartFile) {
- MultipartFile file = (MultipartFile) value;
- value = file.getOriginalFilename(); //获取文件名
- }
-
- requestParams.put(paramNames[i], value);
- }
-
- return requestParams;
- }
通过 @PathVariable 以及 @RequestParam 注解传递的参数无法打印出参数名,因此需要手动拼接一下参数名,同时对文件对象进行了特殊处理,只需获取文件名即可
- @After("requestServer()")
- public void doAfter(JoinPoint joinPoint) {
- LOGGER.info("===============================End========================");
- }
没有业务逻辑只是打印了 End
- @Component
- @Aspect
- public class RequestLogAspect {
- private final static Logger LOGGER = LoggerFactory.getLogger(RequestLogAspect.class);
-
- @Pointcut("execution(* your_package.controller..*(..))")
- public void requestServer() {
- }
-
- @Before("requestServer()")
- public void doBefore(JoinPoint joinPoint) {
- ServletRequestAttributes attributes = (ServletRequestAttributes)
- RequestContextHolder.getRequestAttributes();
- HttpServletRequest request = attributes.getRequest();
-
- LOGGER.info("===============================Start========================");
- LOGGER.info("IP : {}", request.getRemoteAddr());
- LOGGER.info("URL : {}", request.getRequestURL().toString());
- LOGGER.info("HTTP Method : {}", request.getMethod());
- LOGGER.info("Class Method : {}.{}", joinPoint.getSignature().getDeclaringTypeName(),
- joinPoint.getSignature().getName());
- }
-
-
- @Around("requestServer()")
- public Object doAround(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
- long start = System.currentTimeMillis();
- Object result = proceedingJoinPoint.proceed();
- LOGGER.info("Request Params : {}", getRequestParams(proceedingJoinPoint));
- LOGGER.info("Result : {}", result);
- LOGGER.info("Time Cost : {} ms", System.currentTimeMillis() - start);
-
- return result;
- }
-
- @After("requestServer()")
- public void doAfter(JoinPoint joinPoint) {
- LOGGER.info("===============================End========================");
- }
-
- /**
- * 获取入参
- * @param proceedingJoinPoint
- *
- * @return
- * */
- private Map<String, Object> getRequestParams(ProceedingJoinPoint proceedingJoinPoint) {
- Map<String, Object> requestParams = new HashMap<>();
-
- //参数名
- String[] paramNames =
- ((MethodSignature)proceedingJoinPoint.getSignature()).getParameterNames();
- //参数值
- Object[] paramValues = proceedingJoinPoint.getArgs();
-
- for (int i = 0; i < paramNames.length; i++) {
- Object value = paramValues[i];
-
- //如果是文件对象
- if (value instanceof MultipartFile) {
- MultipartFile file = (MultipartFile) value;
- value = file.getOriginalFilename(); //获取文件名
- }
-
- requestParams.put(paramNames[i], value);
- }
-
- return requestParams;
- }
- }
写完以后对自己的代码很满意,但是想着可能还有完善的地方就和朋友交流了一下。emmmm
果然还有继续优化的地方 每个信息都打印一行,在高并发请求下确实会出现请求之间打印日志串行的问题,因为测试阶段请求数量较少没有出现串行的情况,果然生产环境才是第一发展力,能够遇到更多 bug,写更健壮的代码 解决日志串行的问题只要将多行打印信息合并为一行就可以了,因此构造一个对象
- @Around("requestServer()")
- public Object doAround(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
- long start = System.currentTimeMillis();
- ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
- HttpServletRequest request = attributes.getRequest();
- Object result = proceedingJoinPoint.proceed();
- RequestInfo requestInfo = new RequestInfo();
- requestInfo.setIp(request.getRemoteAddr());
- requestInfo.setUrl(request.getRequestURL().toString());
- requestInfo.setHttpMethod(request.getMethod());
- requestInfo.setClassMethod(String.format("%s.%s", proceedingJoinPoint.getSignature().getDeclaringTypeName(),
- proceedingJoinPoint.getSignature().getName()));
- requestInfo.setRequestParams(getRequestParamsByProceedingJoinPoint(proceedingJoinPoint));
- requestInfo.setResult(result);
- requestInfo.setTimeCost(System.currentTimeMillis() - start);
- LOGGER.info("Request Info : {}", JSON.toJSONString(requestInfo));
-
- return result;
- }
-
将 url、http request 这些信息组装成 RequestInfo 对象,再序列化打印对象
打印序列化对象结果而不是直接打印对象是因为序列化有更直观、更清晰,同时可以借助在线解析工具对结果进行解析
是不是还不错
在解决高并发下请求串行问题的同时添加了对
异常请求信息的打印,通过使用 @AfterThrowing 注解对抛出异常的方法进行处理
- @AfterThrowing(pointcut = "requestServer()", throwing = "e")
- public void doAfterThrow(JoinPoint joinPoint, RuntimeException e) {
- ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
- HttpServletRequest request = attributes.getRequest();
- RequestErrorInfo requestErrorInfo = new RequestErrorInfo();
- requestErrorInfo.setIp(request.getRemoteAddr());
- requestErrorInfo.setUrl(request.getRequestURL().toString());
- requestErrorInfo.setHttpMethod(request.getMethod());
- requestErrorInfo.setClassMethod(String.format("%s.%s", joinPoint.getSignature().getDeclaringTypeName(),
- joinPoint.getSignature().getName()));
- requestErrorInfo.setRequestParams(getRequestParamsByJoinPoint(joinPoint));
- requestErrorInfo.setException(e);
- LOGGER.info("Error Request Info : {}", JSON.toJSONString(requestErrorInfo));
- }
对于异常,耗时是没有意义的,因此不统计耗时,而是添加了异常的打印
最后放一下完整日志请求切面代码:
- @Component
- @Aspect
- public class RequestLogAspect {
- private final static Logger LOGGER = LoggerFactory.getLogger(RequestLogAspect.class);
-
- @Pointcut("execution(* your_package.controller..*(..))")
- public void requestServer() {
- }
-
- @Around("requestServer()")
- public Object doAround(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
- long start = System.currentTimeMillis();
- ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
- HttpServletRequest request = attributes.getRequest();
- Object result = proceedingJoinPoint.proceed();
- RequestInfo requestInfo = new RequestInfo();
- requestInfo.setIp(request.getRemoteAddr());
- requestInfo.setUrl(request.getRequestURL().toString());
- requestInfo.setHttpMethod(request.getMethod());
- requestInfo.setClassMethod(String.format("%s.%s", proceedingJoinPoint.getSignature().getDeclaringTypeName(),
- proceedingJoinPoint.getSignature().getName()));
- requestInfo.setRequestParams(getRequestParamsByProceedingJoinPoint(proceedingJoinPoint));
- requestInfo.setResult(result);
- requestInfo.setTimeCost(System.currentTimeMillis() - start);
- LOGGER.info("Request Info : {}", JSON.toJSONString(requestInfo));
-
- return result;
- }
-
-
- @AfterThrowing(pointcut = "requestServer()", throwing = "e")
- public void doAfterThrow(JoinPoint joinPoint, RuntimeException e) {
- ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
- HttpServletRequest request = attributes.getRequest();
- RequestErrorInfo requestErrorInfo = new RequestErrorInfo();
- requestErrorInfo.setIp(request.getRemoteAddr());
- requestErrorInfo.setUrl(request.getRequestURL().toString());
- requestErrorInfo.setHttpMethod(request.getMethod());
- requestErrorInfo.setClassMethod(String.format("%s.%s", joinPoint.getSignature().getDeclaringTypeName(),
- joinPoint.getSignature().getName()));
- requestErrorInfo.setRequestParams(getRequestParamsByJoinPoint(joinPoint));
- requestErrorInfo.setException(e);
- LOGGER.info("Error Request Info : {}", JSON.toJSONString(requestErrorInfo));
- }
-
- /**
- * 获取入参
- * @param proceedingJoinPoint
- *
- * @return
- * */
- private Map<String, Object> getRequestParamsByProceedingJoinPoint(ProceedingJoinPoint proceedingJoinPoint) {
- //参数名
- String[] paramNames = ((MethodSignature)proceedingJoinPoint.getSignature()).getParameterNames();
- //参数值
- Object[] paramValues = proceedingJoinPoint.getArgs();
-
- return buildRequestParam(paramNames, paramValues);
- }
-
- private Map<String, Object> getRequestParamsByJoinPoint(JoinPoint joinPoint) {
- //参数名
- String[] paramNames = ((MethodSignature)joinPoint.getSignature()).getParameterNames();
- //参数值
- Object[] paramValues = joinPoint.getArgs();
-
- return buildRequestParam(paramNames, paramValues);
- }
-
- private Map<String, Object> buildRequestParam(String[] paramNames, Object[] paramValues) {
- Map<String, Object> requestParams = new HashMap<>();
- for (int i = 0; i < paramNames.length; i++) {
- Object value = paramValues[i];
-
- //如果是文件对象
- if (value instanceof MultipartFile) {
- MultipartFile file = (MultipartFile) value;
- value = file.getOriginalFilename(); //获取文件名
- }
-
- requestParams.put(paramNames[i], value);
- }
-
- return requestParams;
- }
-
- @Data
- public class RequestInfo {
- private String ip;
- private String url;
- private String httpMethod;
- private String classMethod;
- private Object requestParams;
- private Object result;
- private Long timeCost;
- }
-
- @Data
- public class RequestErrorInfo {
- private String ip;
- private String url;
- private String httpMethod;
- private String classMethod;
- private Object requestParams;
- private RuntimeException exception;
- }
- }
赶紧给你们的应用加上吧【如果没加的话】,没有日志的话,总怀疑上层出错,但是却拿不出证据
关于 traceId 跟踪定位,可以根据 traceId 跟踪整条调用链,以 log4j2 为例介绍如何加入 traceId
- public class LogInterceptor implements HandlerInterceptor {
- private final static String TRACE_ID = "traceId";
-
- @Override
- public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
- String traceId = java.util.UUID.randomUUID().toString().replaceAll("-", "").toUpperCase();
- ThreadContext.put("traceId", traceId);
-
- return true;
- }
-
- @Override
- public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView)
- throws Exception {
- }
-
- @Override
- public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
- throws Exception {
- ThreadContext. remove(TRACE_ID);
- }
- }
在调用前通过 ThreadContext 加入 traceId,调用完成后移除
<property >[TRACEID:%X{traceId}] %d{HH:mm:ss.SSS} %-5level %class{-1}.%M()/%L - %msg%xEx%n</property>
日志跟踪更方便
DMC 是配置 logback 和 log4j 使用的,使用方式和 ThreadContext 差不多,将 ThreadContext.put 替换为 MDC.put 即可,同时修改日志配置文件。
推荐使用 log4j2,为什么推荐使用 log4j2 可以看下这篇文章:日志框架,选择 Logback Or Log4j2?
log4j2 也是可以配合 MDC 一起使用的
MDC 是 slf4j 包下的,其具体使用哪个日志框架与我们的依赖有关。