Use MDC in lombok slf4j

Question

I am working on an application which is heavily using lombok Slf4j. I want to attach some identifier to the logs. MDC is the one which solves this problem for Slf4j but I want to use that with lombok slf4j. I searched on the net but couldn't find any resources. Is there any way or resources that would be helpful?

What problem do you have? It should work just fine. Show as your code. — talex, Jun 28 '18 at 08:00
I couldn't find the option of importing MDC (if I added lombok slf4j). If I could add that then only I can set some identifier there. — Tejas Joshi, Jun 28 '18 at 09:09

score 1 · Answer 1 · answered Jun 28 '18 at 09:51

It is take some configuration but what you need to do.

Put some dependency in pom.xml

    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>jul-to-slf4j</artifactId>
        <version>1.7.25</version>
    </dependency>
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>1.2.3</version>
    </dependency>

configure logback.xml

<configuration>
    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>%X{x} %msg%n</pattern>
        </encoder>
    </appender>


    <root level="trace">
        <appender-ref ref="STDOUT" />
    </root>
</configuration>

Add some magic to any class

static {
    SLF4JBridgeHandler.removeHandlersForRootLogger();
    SLF4JBridgeHandler.install();
}

and put it all to work

@Log
public class App {    
    public static void main(String[] args) throws IOException {
        MDC.put("x", "MDC var");
        log.info("log message");
    }
}

Run and enjoy your logs:

MDC var log message

special thanks to this answer

Use MDC in lombok slf4j

1 Answers1