Spring Boot :: Enhanced logging information

This example illustrates how you can add additional information to the log output from your Spring Boot application.

The additional information, fx username and requestid, will show up in all log lines without you having to prepend it from your "normal" log lines.

This kind of omnipresent data is called MDC data (Mapped Diagnostic Context). You'll find support for that in the most popular Java logging frameworks.

In this example, the MDC data is based on logback and activated in:

src/main/resources/application.properties

and

src/main/java/com/moelholm/RequestFilter.java

Try it out

Run:

./gradlew clean bootRun 

Open a browser at: http://localhost:8080/greetings/duke

Observe the log output: It captures a request id and a user id and it is added automatically to all loglines emitted during the HTTP request.