Rolling log files by size or by date in springboot apps

Jan 27, 2025

Cowrie

Dev @ Bswen

The purpose of this post

This post demonstrates how to roll log files by date or by size in Spring Boot applications.

Environments

Spring Boot 1.x and 2.x

Rolling log files in Spring Boot apps

What’s the default logging configuration in Spring?

By default, Spring Boot uses Logback as the default logger. However, there are some limitations if you only use application.properties to configure logging:

logging.level.=ERROR  # this is the root logging level for all packages.
logging.level.com.test.sb1jt=DEBUG # this is the project-specific package logging level configuration
logging.file=springboot-logger.log # this is the logging target file

You can configure the root logging level and package logging level, but what if you want to roll log files by date or by size?

Add Logback configuration file to your project

When a file in the Spring Boot classpath has one of the following names, Spring Boot will automatically load it over the default configuration:

logback-spring.xml
logback.xml
logback-spring.groovy
logback.groovy

The logback-spring.xml file is recommended.

Demo rolling log file by size

You can define the rolling policy in src/main/resources/logback-spring.xml as follows:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>

    <!-- All log files located in logs file of the project -->
    <property name="LOGS" value="./logs" />

    <!-- Define the console log format -->
    <appender name="Console"
              class="ch.qos.logback.core.ConsoleAppender">
        <layout class="ch.qos.logback.classic.PatternLayout">
            <Pattern>
                %black(%d{ISO8601}) %highlight(%-5level) [%blue(%t)] %yellow(%C{1.}): %msg%n%throwable
            </Pattern>
        </layout>
    </appender>

    <appender name="RollingFileBySize" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOGS}/spring-boot-loggerbysize.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
            <!-- rollover daily -->
            <fileNamePattern>${LOGS}/spring-boot-loggerbysize-%d{yyyy-MM-dd}.%i.log</fileNamePattern>
            <!-- each file should be at most 1MB, keep 6 days worth of history, but at most 3M -->
            <maxFileSize>1MB</maxFileSize>
            <maxHistory>6</maxHistory>
            <totalSizeCap>3MB</totalSizeCap>
        </rollingPolicy>
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
        </encoder>
    </appender>

    <!-- LOG everything at error level -->
    <root level="error">
        <appender-ref ref="RollingFileBySize" />
        <appender-ref ref="Console" />
    </root>

    <!-- LOG "com.test*" at TRACE level -->
    <logger name="com.test" level="trace" additivity="false">
        <appender-ref ref="RollingFileBySize" />
        <appender-ref ref="Console" />
    </logger>

</configuration>

You can test this by running an infinite loop that prints a lot of logs. You will get files like these:

-rw-r--r--  1 zzz  staff   1.0M May 25 18:21 spring-boot-loggerbysize-2019-05-25.0.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:21 spring-boot-loggerbysize-2019-05-25.1.log
-rw-r--r--  1 zzz  staff   317K May 25 18:22 spring-boot-loggerbysize.log

Demo rolling log file by date

You can define the date-rolling policy in src/main/resources/logback-spring.xml as follows:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>

    <!-- All log files located in logs file of the project -->
    <property name="LOGS" value="./logs" />

    <!-- Define the console log format -->
    <appender name="Console"
              class="ch.qos.logback.core.ConsoleAppender">
        <layout class="ch.qos.logback.classic.PatternLayout">
            <Pattern>
                %black(%d{ISO8601}) %highlight(%-5level) [%blue(%t)] %yellow(%C{1.}): %msg%n%throwable
            </Pattern>
        </layout>
    </appender>

    <appender name="RollingFileByDate"
              class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOGS}/spring-boot-loggerbydate.log</file>
        <encoder
                class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
        </encoder>

        <rollingPolicy
                class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <!-- rollover daily and when the file reaches 10 MegaBytes -->
            <fileNamePattern>${LOGS}/spring-boot-loggerbydate-%d{yyyy-MM-dd}.%i.log
            </fileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy
                    class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>1MB</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
        </rollingPolicy>
    </appender>

    <!-- LOG everything at error level -->
    <root level="error">
        <appender-ref ref="RollingFileByDate" />
        <appender-ref ref="Console" />
    </root>

    <!-- LOG "com.test*" at TRACE level -->
    <logger name="com.test" level="trace" additivity="false">
        <appender-ref ref="RollingFileByDate" />
        <appender-ref ref="Console" />
    </logger>

</configuration>

You can test this by running an infinite loop that prints a lot of logs. You will get files like these:

-rw-r--r--  1 zzz  staff   393K May 25 18:34 spring-boot-loggerbydate.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:31 spring-boot-loggerbydate-2019-05-25.0.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:31 spring-boot-loggerbydate-2019-05-25.1.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:31 spring-boot-loggerbydate-2019-05-25.2.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:32 spring-boot-loggerbydate-2019-05-25.3.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:32 spring-boot-loggerbydate-2019-05-25.4.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:32 spring-boot-loggerbydate-2019-05-25.5.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:33 spring-boot-loggerbydate-2019-05-25.6.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:33 spring-boot-loggerbydate-2019-05-25.7.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:33 spring-boot-loggerbydate-2019-05-25.8.log
-rw-r--r--  1 zzz  staff   1.0M May 25 18:34 spring-boot-loggerbydate-2019-05-25.9.log

Summary

In this post, we explored how to configure log file rotation by size or by date in Spring Boot applications using Logback. We covered the default logging configuration, how to add a Logback configuration file, and provided examples of rolling log files by size and by date. By following these steps, you can effectively manage log files in your Spring Boot applications.

Final Words + More Resources

My intention with this article was to help others who might be considering solving such a problem. So I hope that’s been the case here. If you still have any questions, don’t hesitate to ask me by email: Email me

Here are also the most important links from this article along with some further resources that will help you in this scope:

👨‍💻 logback logging appender configurations

Oh, and if you found these resources useful, don’t forget to support me by starring the repo on GitHub!