Spring Boot 2.2.2中Micrometer Tracing无traceId/spanId输出问题求助

我正在使用Spring Boot 2.2.2.RELEASE版本，控制器类如下：

@RestController
public class HelloController {

    private static final Logger LOGGER = LogManager.getLogger(HelloController.class);
    @GetMapping(value = "{userId}")
    public String test(@PathVariable("userId") String userId){
        LOGGER.info("user =  {}",userId);
        return "ok";
    }
}

pom.xml已添加Micrometer Tracing依赖，同时使用Log4j2日志库：

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>loglama</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>loglama</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
         </properties>
    <dependencies>

        <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.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>2.17.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-jul</artifactId>
            <version>2.17.0</version>
        </dependency>

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.17.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-slf4j-impl</artifactId>
            <version>2.17.0</version>
        </dependency>

        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-log4j-appender</artifactId>
            <version>3.5.0</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <!-- Micrometer Tracing -->
        <dependency>
            <groupId>io.micrometer</groupId>
            <artifactId>micrometer-tracing</artifactId>
            <version>1.1.2</version>
        </dependency>

        <!-- Micrometer Tracing Bridge Brave -->
        <dependency>
            <groupId>io.micrometer</groupId>
            <artifactId>micrometer-tracing-bridge-brave</artifactId>
            <version>1.1.2</version>
        </dependency>


    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>io.micrometer</groupId>
                <artifactId>micrometer-tracing-bom</artifactId>
                <version>1.1.2</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

日志格式已添加[%X{traceId},%X{spanId}]：

appender.console.layout.pattern = [%d{yyy-MM-dd HH:mm:ss:SSS}] [%X{traceId},%X{spanId}] [%p] - %l - %m%n

日志输出如下：

[2023-07-11 10:45:49:889] [,] [INFO] - com.example.loglama.controller.HelloController.test(HelloController.java:18) - user =  demo123

可以看到traceId和spanId为空，且公司不允许升级Spring Boot版本，请问如何解决该问题？

Spring Boot 2.2.2.RELEASE未与Micrometer Tracing深度集成，当前依赖的组件需要额外配置才能绑定Web请求链路并将traceId/spanId写入日志MDC，具体步骤如下：

• 补充Brave依赖
  原pom中缺少Brave对Spring Web的拦截器和Log4j2的MDC适配组件，添加以下依赖（版本与Micrometer Tracing 1.1.2兼容）：

  <!-- Brave Spring Web拦截器：为HTTP请求创建trace/span -->
  <dependency>
      <groupId>io.zipkin.brave</groupId>
      <artifactId>brave-spring-web</artifactId>
      <version>5.14.1</version>
  </dependency>
  <!-- Brave Log4j2集成：将traceId/spanId写入MDC -->
  <dependency>
      <groupId>io.zipkin.brave</groupId>
      <artifactId>brave-log4j2</artifactId>
      <version>5.14.1</version>
  </dependency>
  

• 手动注册Brave TraceFilter
  Spring Boot 2.2.2不会自动注册Brave的Web拦截器，需手动配置Bean：

  import brave.Tracing;
  import brave.spring.web.TracingFilter;
  import org.springframework.context.annotation.Bean;
  import org.springframework.context.annotation.Configuration;
  
  @Configuration
  public class TracingConfig {
  
      @Bean
      public TracingFilter tracingFilter(Tracing tracing) {
          return new TracingFilter(tracing);
      }
  }
  

  该Filter会为每个HTTP请求生成trace和span，并将上下文存入ThreadLocal，供Brave的Log4j2组件读取并写入MDC。

• 验证MDC键名匹配
  Brave默认向MDC写入的键就是traceId和spanId，与你现有日志格式中的配置一致，无需修改日志模板。

• 启用Micrometer Tracing配置
  在application.properties中添加配置确保组件生效：

  management.tracing.enabled=true
  

完成上述配置后重启应用，发起HTTP请求即可在日志中看到正常的traceId和spanId。

内容的提问来源于stack exchange，提问作者Sezer Aydın