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1.背景
SpringBoot项目中，之前都是在controller方法的第一行手动打印 log，return之前再打印返回值。有多个返回点时，就需要出现多少重复代码，过多的非业务代码显得十分凌乱。
本文将采用AOP 配置自定义注解实现 入参、出参的日志打印（方法的入参和返回值都采用 fastjson 序列化）。
2.设计思路
将特定包下所有的controller生成代理类对象，并交由Spring容器管理，并重写invoke方法进行增强(入参、出参的打印).
3.核心代码
3.1 自定义注解
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Import({InteractRecordBeanPostProcessor.class})
public @interface EnableInteractRecord {
/**
* app对应controller包名
*/
String[] basePackages() default {};
/**
* 排除某些包
*/
String[] exclusions() default {};
}3.2 实现BeanFactoryPostProcessor接口
作用：获取EnableInteractRecord注解对象，用于获取需要创建代理对象的包名，以及需要排除的包名
@Component
public class InteractRecordFactoryPostProcessor implements BeanFactoryPostProcessor {
private static Logger logger = LoggerFactory.getLogger(InteractRecordFactoryPostProcessor.class);
private EnableInteractRecord enableInteractRecord;
@Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
try {
String[] names = beanFactory.getBeanNamesForAnnotation(EnableInteractRecord.class);
for (String name : names) {
enableInteractRecord = beanFactory.findAnnotationOnBean(name, EnableInteractRecord.class);
logger.info("开启交互记录 ", enableInteractRecord);
}
} catch (Exception e) {
logger.error("postProcessBeanFactory() Exception ", e);
}
}
public EnableInteractRecord getEnableInteractRecord() {
return enableInteractRecord;
}
}3.3 实现MethodInterceptor编写打印日志逻辑
作用：进行入参、出参打印，包含是否打印逻辑
@Component
public class ControllerMethodInterceptor implements MethodInterceptor {
private static Logger logger = LoggerFactory.getLogger(ControllerMethodInterceptor.class);
// 请求开始时间
ThreadLocal<Long> startTime = new ThreadLocal<>();
private String localIp = "";
@PostConstruct
public void init() {
try {
localIp = InetAddress.getLocalHost().getHostAddress();
} catch (UnknownHostException e) {
logger.error("本地IP初始化失败 : ", e);
}
}
@Override
public Object invoke(MethodInvocation invocation) {
pre(invocation);
Object result;
try {
result = invocation.proceed();
post(invocation, result);
return result;
} catch (Throwable ex) {
logger.error("controller 执行异常: ", ex);
error(invocation, ex);
}
return null;
}
public void error(MethodInvocation invocation, Throwable ex) {
String msgText = ex.getMessage();
logger.info(startTime.get() + " 异常，请求结束");
logger.info("RESPONSE : " + msgText);
logger.info("SPEND TIME : " + (System.currentTimeMillis() - startTime.get()));
}
private void pre(MethodInvocation invocation) {
long now = System.currentTimeMillis();
startTime.set(now);
logger.info(now + " 请求开始");
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
HttpServletRequest request = attributes.getRequest();
logger.info("URL : " + request.getRequestURL().toString());
logger.info("HTTP_METHOD : " + request.getMethod());
logger.info("REMOTE_IP : " + getRemoteIp(request));
logger.info("LOCAL_IP : " + localIp);
logger.info("METHOD : " + request.getMethod());
logger.info("CLASS_METHOD : " + getTargetClassName(invocation) + "." + invocation.getMethod().getName());
// 获取请求头header参数
Map<String, String> map = new HashMap<String, String>();
Enumeration<String> headerNames = request.getHeaderNames();
while (headerNames.hasMoreElements()) {
String key = (String) headerNames.nextElement();
String value = request.getHeader(key);
map.put(key, value);
}
logger.info("HEADERS : " + JSONObject.toJSONString(map));
Date createTime = new Date(now);
// 请求报文
Object[] args = invocation.getArguments();// 参数
String msgText = "";
Annotation[][] annotationss = invocation.getMethod().getParameterAnnotations();
for (int i = 0; i < args.length; i++) {
Object arg = args[i];
if (!(arg instanceof ServletRequest)
&& !(arg instanceof ServletResponse)
&& !(arg instanceof Model)) {
RequestParam rp = null;
Annotation[] annotations = annotationss[i];
for (Annotation annotation : annotations) {
if (annotation instanceof RequestParam) {
rp = (RequestParam) annotation;
}
}
if (msgText.equals("")) {
msgText += (rp != null ? rp.value() + " = " : " ") + JSONObject.toJSONString(arg);
} else {
msgText += "," + (rp != null ? rp.value() + " = " : " ") + JSONObject.toJSONString(arg);
}
}
}
logger.info("PARAMS : " + msgText);
}
private void post(MethodInvocation invocation, Object result) {
logger.info(startTime.get() + " 请求结束");
if (!(result instanceof ModelAndView)) {
String msgText = JSONObject.toJSONString(result);
logger.info("RESPONSE : " + msgText);
}
logger.info("SPEND TIME : " + (System.currentTimeMillis() - startTime.get()));
}
private String getRemoteIp(HttpServletRequest request) {
String remoteIp = null;
String remoteAddr = request.getRemoteAddr();
String forwarded = request.getHeader("X-Forwarded-For");
String realIp = request.getHeader("X-Real-IP");
if (realIp == null) {
if (forwarded == null) {
remoteIp = remoteAddr;
} else {
remoteIp = remoteAddr + "/" + forwarded.split(",")[0];
}
} else {
if (realIp.equals(forwarded)) {
remoteIp = realIp;
} else {
if (forwarded != null) {
forwarded = forwarded.split(",")[0];
}
remoteIp = realIp + "/" + forwarded;
}
}
return remoteIp;
}
private String getTargetClassName(MethodInvocation invocation) {
String targetClassName = "";
try {
targetClassName = AopTargetUtils.getTarget(invocation.getThis()).getClass().getName();
} catch (Exception e) {
targetClassName = invocation.getThis().getClass().getName();
}
return targetClassName;
}
}AopTargetUtils：
public class AopTargetUtils {
/**
* 获取 目标对象
* @param proxy 代理对象
* @return
* @throws Exception
*/
public static Object getTarget(Object proxy) throws Exception {
if(!AopUtils.isAopProxy(proxy)) {
return proxy;//不是代理对象
}
if(AopUtils.isJdkDynamicProxy(proxy)) {
return getJdkDynamicProxyTargetObject(proxy);
} else { //cglib
return getCglibProxyTargetObject(proxy);
}
}
private static Object getCglibProxyTargetObject(Object proxy) throws Exception {
Field h = proxy.getClass().getDeclaredField("CGLIB$CALLBACK_0");
h.setAccessible(true);
Object dynamicAdvisedInterceptor = h.get(proxy);
Field advised = dynamicAdvisedInterceptor.getClass().getDeclaredField("advised");
advised.setAccessible(true);
Object target = ((AdvisedSupport)advised.get(dynamicAdvisedInterceptor)).getTargetSource().getTarget();
return getTarget(target);
}
private static Object getJdkDynamicProxyTargetObject(Object proxy) throws Exception {
Field h = proxy.getClass().getSuperclass().getDeclaredField("h");
h.setAccessible(true);
AopProxy aopProxy = (AopProxy) h.get(proxy);
Field advised = aopProxy.getClass().getDeclaredField("advised");
advised.setAccessible(true);
Object target = ((AdvisedSupport)advised.get(aopProxy)).getTargetSource().getTarget();
return getTarget(target);
}
}3.4 实现BeanPostProcessor接口
作用：筛选出需要生成代理的类，并生成代理类，返回给Spring容器管理。
public class InteractRecordBeanPostProcessor implements BeanPostProcessor {
private static Logger logger = LoggerFactory.getLogger(InteractRecordBeanPostProcessor.class);
@Autowired
private InteractRecordFactoryPostProcessor interactRecordFactoryPostProcessor;
@Autowired
private ControllerMethodInterceptor controllerMethodInterceptor;
private String BASE_PACKAGES[];//需要拦截的包
private String EXCLUDING[];// 过滤的包
//一层目录匹配
private static final String ONE_REGEX = "[a-zA-Z0-9_]+";
//多层目录匹配
private static final String ALL_REGEX = ".*";
private static final String END_ALL_REGEX = "*";
@PostConstruct
public void init() {
EnableInteractRecord ir = interactRecordFactoryPostProcessor.getEnableInteractRecord();
BASE_PACKAGES = ir.basePackages();
EXCLUDING = ir.exclusions();
}
@Override
public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
try {
if (interactRecordFactoryPostProcessor.getEnableInteractRecord() != null) {
// 根据注解配置的包名记录对应的controller层
if (BASE_PACKAGES != null && BASE_PACKAGES.length > 0) {
Object proxyObj = doEnhanceForController(bean);
if (proxyObj != null) {
return proxyObj;
}
}
}
} catch (Exception e) {
logger.error("postProcessAfterInitialization() Exception ", e);
}
return bean;
}
@Override
public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
return bean;
}
private Object doEnhanceForController(Object bean) {
String beanPackageName = getBeanPackageName(bean);
if (StringUtils.isNotBlank(beanPackageName)) {
for (String basePackage : BASE_PACKAGES) {
if (matchingPackage(basePackage, beanPackageName)) {
if (EXCLUDING != null && EXCLUDING.length > 0) {
for (String excluding : EXCLUDING) {
if (matchingPackage(excluding, beanPackageName)) {
return bean;
}
}
}
Object target = null;
try {
target = AopTargetUtils.getTarget(bean);
} catch (Exception e) {
logger.error("AopTargetUtils.getTarget() exception", e);
}
if (target != null) {
boolean isController = target.getClass().isAnnotationPresent(Controller.class);
boolean isRestController = target.getClass().isAnnotationPresent(RestController.class);
if (isController || isRestController) {
ProxyFactory proxy = new ProxyFactory();
proxy.setTarget(bean);
proxy.addAdvice(controllerMethodInterceptor);
return proxy.getProxy();
}
}
}
}
}
return null;
}
private static boolean matchingPackage(String basePackage, String currentPackage) {
if (StringUtils.isEmpty(basePackage) || StringUtils.isEmpty(currentPackage)) {
return false;
}
if (basePackage.indexOf("*") != -1) {
String patterns[] = StringUtils.split(basePackage, ".");
for (int i = 0; i < patterns.length; i++) {
String patternNode = patterns[i];
if (patternNode.equals("*")) {
patterns[i] = ONE_REGEX;
}
if (patternNode.equals("**")) {
if (i == patterns.length - 1) {
patterns[i] = END_ALL_REGEX;
} else {
patterns[i] = ALL_REGEX;
}
}
}
String basePackageRegex = StringUtils.join(patterns, "\.");
Pattern r = Pattern.compile(basePackageRegex);
Matcher m = r.matcher(currentPackage);
return m.find();
} else {
return basePackage.equals(currentPackage);
}
}
private String getBeanPackageName(Object bean) {
String beanPackageName = "";
if (bean != null) {
Class<?> beanClass = bean.getClass();
if (beanClass != null) {
Package beanPackage = beanClass.getPackage();
if (beanPackage != null) {
beanPackageName = beanPackage.getName();
}
}
}
return beanPackageName;
}
}3.5 启动类配置注解
@EnableInteractRecord(basePackages = “com.test.test.controller”,exclusions = “com.test.demo.controller”)
以上即可实现入参、出参日志统一打印，并且可以将特定的controller集中管理，并不进行日志的打印（及不进生成代理类）。
4.出现的问题(及其解决办法)
实际开发中，特定不需要打印日志的接口，无法统一到一个包下。大部分需要打印的接口，和不需要打印的接口，大概率会参杂在同一个controller中，根据以上设计思路，无法进行区分。
解决办法：
自定义排除入参打印注解
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface ExcludeReqLog {
}自定义排除出参打印注解
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface ExcludeRespLog {
}增加逻辑
// 1.在解析requestParam之前进行判断
Method method = invocation.getMethod();
Annotation[] declaredAnnotations = method.getDeclaredAnnotations();
boolean flag = true;
for (Annotation annotation : declaredAnnotations) {
if (annotation instanceof ExcludeReqLog) {
flag = false;
}
}
if (!flag) {
logger.info("该方法已排除，不打印入参");
return;
}
// 2.在解析requestResp之前进行判断
Method method = invocation.getMethod();
Annotation[] declaredAnnotations = method.getDeclaredAnnotations();
boolean flag = true;
for (Annotation annotation : declaredAnnotations) {
if (annotation instanceof ExcludeRespLog) {
flag = false;
}
}
if (!flag) {
logger.info("该方法已排除，不打印出参");
return;
}使用方法
// 1.不打印入参
@PostMapping("/uploadImg")
@ExcludeReqLog
public Result<List<Demo>> uploadIdeaImg(@RequestParam(value = "imgFile", required = false) MultipartFile[] imgFile) {
return demoService.uploadIdeaImg(imgFile);
}
//2.不打印出参
@PostMapping("/uploadImg")
@ExcludeRespLog
public Result<List<Demo>> uploadIdeaImg(@RequestParam(value = "imgFile", required = false) MultipartFile[] imgFile) {
return demoService.uploadIdeaImg(imgFile);
}