Spring Boot中实现特定用户日志动态追踪指南

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
    <exclusions>
        <exclusion>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>

import org.apache.logging.log4j.ThreadContext;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Optional;

@Component
public class UserContextInterceptor implements HandlerInterceptor {

    public static final String USER_ID_KEY = "userId"; // 定义ThreadContext中存储用户ID的键

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        // 模拟从请求头或会话中获取用户ID
        // 实际应用中，这里会从认证信息（如JWT token、Session）中提取用户ID
        String userId = request.getHeader("X-User-ID"); // 假设用户ID在请求头中

        // 如果获取到用户ID，则放入ThreadContext
        Optional.ofNullable(userId)
                .ifPresent(id -> ThreadContext.put(USER_ID_KEY, id));

        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        // 在请求处理完成后，清空ThreadContext，防止内存泄漏和信息混淆
        ThreadContext.remove(USER_ID_KEY);
    }
}

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class WebConfig implements WebMvcConfigurer {

    private final UserContextInterceptor userContextInterceptor;

    public WebConfig(UserContextInterceptor userContextInterceptor) {
        this.userContextInterceptor = userContextInterceptor;
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(userContextInterceptor)
                .addPathPatterns("/**"); // 拦截所有路径
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN" monitorInterval="30"> <!-- monitorInterval设置Log4j2每隔30秒检查配置文件变更 -->

    <Properties>
        <Property name="LOG_PATTERN">%d{yyyy-MM-dd HH:mm:ss.SSS} %-5p [%t] %c{1.} [%X{userId}] - %m%n</Property>
    </Properties>

    <Appenders>
        <Console name="ConsoleAppender" target="SYSTEM_OUT">
            <PatternLayout pattern="${LOG_PATTERN}"/>
            <!-- 应用MutableThreadContextMapFilter到ConsoleAppender -->
            <Filters>
                <MutableThreadContextMapFilter onMismatch="NEUTRAL" onMatch="DENY">
                    <!-- 
                        location: 指定外部JSON配置文件的路径。
                        reloadInterval: 指定Log4j2检查配置文件更新的间隔（秒）。
                        key: 指定ThreadContext中用于匹配的键，应与UserContextInterceptor中的USER_ID_KEY一致。
                    -->
                    <KeyValuePair key="loggingUsersConfigLocation" value="classpath:logging-users-config.json"/>
                    <KeyValuePair key="reloadInterval" value="10"/>
                    <KeyValuePair key="keyToMatch" value="userId"/>
                </MutableThreadContextMapFilter>
            </Filters>
        </Console>

        <!-- 如果需要文件日志，也可以在这里添加FileAppender并应用相同的过滤器 -->
        <!--
        <File name="FileAppender" fileName="logs/application.log">
            <PatternLayout pattern="${LOG_PATTERN}"/>
            <Filters>
                <MutableThreadContextMapFilter onMismatch="NEUTRAL" onMatch="DENY">
                    <KeyValuePair key="loggingUsersConfigLocation" value="classpath:logging-users-config.json"/>
                    <KeyValuePair key="reloadInterval" value="10"/>
                    <KeyValuePair key="keyToMatch" value="userId"/>
                </MutableThreadContextMapFilter>
            </Filters>
        </File>
        -->
    </Appenders>

    <Loggers>
        <Root level="info"> <!-- 默认根日志级别 -->
            <AppenderRef ref="ConsoleAppender"/>
            <!-- <AppenderRef ref="FileAppender"/> -->
        </Root>
    </Loggers>

</Configuration>

{
  "users": [
    {
      "id": "123",
      "level": "DEBUG"
    },
    {
      "id": "456",
      "level": "TRACE"
    }
  ],
  "defaultLevel": "INFO"
}

            <Filters>
                <MutableThreadContextMapFilter onMismatch="NEUTRAL" onMatch="ACCEPT"> <!-- 匹配时接受 -->
                    <KeyValuePair key="loggingUsersConfigLocation" value="classpath:logging-users-config.json"/>
                    <KeyValuePair key="reloadInterval" value="10"/>
                    <KeyValuePair key="keyToMatch" value="userId"/>
                </MutableThreadContextMapFilter>
                <!-- 
                     重要：为了确保只有特定用户的日志被放行，
                     我们需要在MutableThreadContextMapFilter之后添加一个通用的ThresholdFilter，
                     来拒绝所有未被MutableThreadContextMapFilter接受的低级别日志。
                     如果MutableThreadContextMapFilter onMismatch="NEUTRAL"，
                     那么没有匹配的用户会继续往下走，被这个ThresholdFilter拒绝。
                     如果匹配的用户被ACCEPT了，那么它会跳过这个ThresholdFilter。
                -->
                <ThresholdFilter level="ERROR" onMatch="ACCEPT" onMismatch="DENY"/> 
            </Filters>

    <Loggers>
        <Root level="error"> <!-- 默认根日志级别设置为error，只打印错误日志 -->
            <AppenderRef ref="ConsoleAppender"/>
        </Root>
    </Loggers>