Java web app catalina logs not written to log file when running in Eclipse

Question

I have a Java web app that I run in Eclipse for my development environment. I use logback for logging to a custom file. The problem is certain logging statements, specifically those that traditionally go to catalina.out, do not end up in my log file. They do show up in my Eclipse console, but not in my custom logback log file.

When I run the same app in tomcat outside of Eclipse (via startup.bat), those catalina logging statements do get captured in a catalina.out file. But when running in Eclipse no catalina.out is created, so those logs don't persist.

Here's my logback-test.xml:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <!-- RollingFileAppender that rolls based on size and time -->
    <appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${catalina.base}/logs/mylog.log</file>
        <encoder>
            <pattern>%date [%thread] %-5level %logger{10} [%file:%line] - %msg%n</pattern>
        </encoder>
        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
            <!-- rollover daily -->
            <fileNamePattern>${catalina.base}/logs/mylog.%d{yyyy-MM-dd}.%i.log</fileNamePattern>
            <!-- each file at most 20MB; keep 10 files worth of history, max total 20GB -->
            <maxFileSize>20MB</maxFileSize>
            <maxHistory>10</maxHistory>
            <totalSizeCap>20GB</totalSizeCap>
        </rollingPolicy>
    </appender>

    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>logback-test %date [%thread] %highlight(%-5level) %logger{10} - %msg%n</pattern>
        </encoder>
    </appender>

    <appender name="STDERR" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>logback-test %date [%thread] %highlight(%-5level) %logger{10} - %msg%n</pattern>
        </encoder>
    </appender>

    <!-- set logging levels for specific packages -->        
    <logger name="org.apache.catalina.startup" level="INFO"/>

    <!-- set level of the root logger and associate it with both appenders -->
    <root level="INFO">
        <appender-ref ref="FILE"/>
        <appender-ref ref="STDOUT"/>
        <appender-ref ref="STDERR"/>
    </root>
</configuration>

Woodchuck · Accepted Answer · 2020-05-10T23:10:45.447

This answer resolved my question: https://stackoverflow.com/a/5045247/3368818

Apparently, if, while running an app on tomcat via Eclipse, you want to capture the catalina logs in a file, you need to specify that via the Eclipse tomcat launch configuration settings.

I guess in a way this makes sense in that the catalina logs are perhaps not application specific, so maybe outside the scope of logback appenders. But on the other hand, shouldn't they get written to a log file by default anyway, just as they do if you launch your tomcat server outside of Eclipse?

Java web app catalina logs not written to log file when running in Eclipse

1 Answers1