How to Set the Logging Level in Spring Boot

Spring Boot makes application development easier by providing sensible defaults and eliminating much of the boilerplate configuration. One aspect of configuration that often requires tweaking is logging. Effective logging is crucial for debugging and monitoring your application, and Spring Boot offers a straightforward way to adjust logging levels.

Understanding Spring Boot Logging

Spring Boot uses Apache Commons Logging for internal logging but defaults to using Logback as the logging implementation. Logback is a powerful and flexible logging framework that allows you to control logging levels for different packages or classes.

Using application.properties

The application.properties file remains a popular choice for its simplicity. Here’s how you can use it to configure logging:

# Global logging level
logging.level.root=INFO

# Package-specific logging levels
logging.level.org.springframework.web=DEBUG
logging.level.com.yourcompany=TRACE

# Class-specific logging level
logging.level.com.yourcompany.service.MyService=DEBUG

Using application.yml

For those who prefer YAML syntax, application.yml offers a more structured approach:

logging:
  level:
    root: INFO
    org.springframework.web: DEBUG
    com.yourcompany: TRACE
    com.yourcompany.service.MyService: DEBUG

Log4j2 (log4j2-spring.xml)

<Configuration status="WARN">
    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
        </Console>
    </Appenders>
    <Loggers>
        <Root level="info">
            <AppenderRef ref="Console"/>
        </Root>
        <Logger name="org.springframework.web" level="debug"/>
        <Logger name="com.yourcompany" level="trace"/>
    </Loggers>
</Configuration>

There are also dynamic logging configuration, you can use Java code or Logback (logback-spring.xml).

By understanding these various methods, you can choose the best approach for your specific needs, whether you’re in development, testing, or production environments.

Remember, effective logging is about finding the right balance – capturing enough information to be useful without overwhelming your system.

We Want to Hear From You!

What logging configurations do you find most useful for your Spring Boot applications? Do you have any tips or tricks for managing logs effectively? Share your experiences or ask any questions you might have about logging in Spring Boot in the comments below.