logging.include-application-name has no effect when using log4j2

[duoduobingbing]

As the title says, when creating a fresh Spring Boot 3.2.0 project the console logs generated by Logback look like this by default

2023-12-01T08:57:37.478+01:00  INFO 22208 --- [           main] com.example.demo.DemoApplicationTests    : No active profile set, falling back to 1 default profile: "default"
2023-12-01T08:57:38.181+01:00  INFO 22208 --- [           main] com.example.demo.DemoApplicationTests    : Started DemoApplicationTests in 0.832 seconds (process running for 1.308)

After switching from Logback to Log4j2 the console logs look like this

2023-12-01T09:02:33.314+01:00  INFO 14764 --- ${sys:LOGGED_APPLICATION_NAME}[           main] c.e.d.DemoApplicationTests               : No active profile set, falling back to 1 default profile: "default"
2023-12-01T09:02:33.938+01:00  INFO 14764 --- ${sys:LOGGED_APPLICATION_NAME}[           main] c.e.d.DemoApplicationTests               : Started DemoApplicationTests in 0.814 seconds (process running for 1.415)

Setting the new logging.include-application-name property to false does not make the ${sys:LOGGED_APPLICATION_NAME} disappear from the logged console output.

Here is a small reproducer: demo-reproducer.zip that can be run with mvn spring-boot:run

[mhalbritter]

Thanks for the report and the reproducer. This looks like a bug.

[mhalbritter]

When setting the spring.application.name=my-app, the log output looks sane, as [my-app] is included instead of that ugly placeholder.

[itsAkshayDubey]

Hi @mhalbritter ,

I would appreciate it if you could assign this bug to me, allowing me to work on resolving it.

Thanks,
Akshay

[itsAkshayDubey]

When setting the spring.application.name=my-app, the log output looks sane, as [my-app] is included instead of that ugly placeholder.

When logging.include-application-name is set to false, the ${sys:LOGGED_APPLICATION_NAME} placeholder appears in the logs, irrespective of whether the spring.application.name property is present or not. On the other hand, when logging.include-application-name is set to its default value of true, the ${sys:LOGGED_APPLICATION_NAME} placeholder is only present in the logs when the spring.application.name property is not set.

[ilies-bel]

Hello,

I'd like to correct this problem, my PR is ready, please tell me if I have the right to propose it.

Thanks

[philwebb]

@ilies-bel A pull request would be most welcome, please submit it at your earliest convenience.

[ilies-bel]

Done,
I am new to this project, tell me if I forgot anything

[philwebb]

Closing in favor of PR #38847. Thanks @ilies-bel!