=============
后端_记录日志
=============

1 创建日志注解

/ysdblog-api/src/main/java/com/weihome/ysdblog/common/aop/LogAnnotation.java：

@Target({ElementType.METHOD}) // 方法注解
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface LogAnnotation {
    String module() default "";
    String operation() default "";
}

2 创建日志切面

/ysdblog-api/src/main/java/com/weihome/ysdblog/common/aop/LogAspect.java：

@Component
@Aspect
@Slf4j
public class LogAspect {
    // LogAnnotation注解加在哪个方法上，哪个方法就是切点
    @Pointcut("@annotation(com.weihome.ysdblog.common.aop.LogAnnotation)")
    public void pointcut() {}

    // 环绕通知，在切点方法执行之前和之后执行增强操作
    @Around("pointcut()")
    public Object advice(ProceedingJoinPoint joinPoint) throws Throwable {
        // 开始时间
        long beginTime = System.currentTimeMillis();
        // 执行切点
        Object result = joinPoint.proceed();
        // 计算耗时
        long elapsedTime = System.currentTimeMillis() - beginTime;
        // 记录日志
        wlog(joinPoint, elapsedTime);
        // 返回结果
        return result;
    }

    private void wlog(ProceedingJoinPoint joinPoint, long elapsedTime) {
        log.info("---------------- YSDBLOG ----------------");
        // 模块和操作
        MethodSignature signature =
            (MethodSignature) joinPoint.getSignature();
        Method method = signature.getMethod();
        LogAnnotation annotation =
            method.getAnnotation(LogAnnotation.class);
        log.info("Module: {}", annotation.module());
        log.info("Operation: {}", annotation.operation());
        // 类名和方法名
        String className = joinPoint.getTarget().getClass().getName();
        String methodName =signature.getName();
        log.info("Method: {}", className + "." + methodName + "()");
        // 方法参数
        Object[] args = joinPoint.getArgs();
        log.info("Arguments: {}", JSON.toJSONString(args[0]));
        // 请求源IP
        HttpServletRequest request =
            HttpContextUtils.getHttpServletRequest();
        log.info("IP: {}", IPUtils.getIpAddr(request));
        // 方法耗时
        log.info("Elapsed Time: {} ms", elapsedTime);
        log.info("-----------------------------------------");
    }
}

3 添加日志注解

/ysdblog-api/src/main/java/com/weihome/ysdblog/controller/ArticleController.java：

...
public class ArticleController {
    ...
    @LogAnnotation(module = "文章", operation = "分页查询文章列表")
    public Result list(...) {
        ...
    }
    ...
}

4 运行测试

Postman
    POST
        localhost:8888/article/list
    Body
{
    "page": "1",
    "pageSize": "10"
}
-----------------------------------
...

后端日志：

---------------- YSDBLOG ----------------
Module: 文章
Operation: 分页查询文章列表
Method: com.weihome.ysdblog.controller.ArticleController.list()
Arguments: {"page":1,"pageSize":10}
IP: 0:0:0:0:0:0:0:1
Elapsed time: 406 ms
-----------------------------------------