How can I set log file max size on android

Question

I'm using microlog4android to log to file. The question is how can set maximum file size?

microlog4android FileAppender class has two methods: getLogSize (which always return -1 ) and clear. I could clear log when it reaches certain size but getLogSize doesn't seem to work.

Is there any better, more mature android logging solution that I'm not aware of?

Answer 1

You can use logback-android with the RollingFileAppender and SizeBasedTriggeringPolicy, but you should be aware of a bug (src) that may cause your working log file to exceed the max file size. A workaround is to subclass the triggering policy to bypass the bug:

package com.example;

import java.io.File;
import ch.qos.logback.core.util.FileSize;

public class SizeBasedTriggeringPolicy<E> extends ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy<E> {
    @Override
    public boolean isTriggeringEvent(final File activeFile, final E event) {
        return (activeFile.length() >= FileSize.valueOf(getMaxFileSize()).getSize());
    }
}

Here's an example config (based on the Logback manual and including the workaround above) that you can put into your AndroidManifest.xml. I tested this in Android 4.0.3 emulator, but I imagine it would also work in earlier versions.

<logback>
    <configuration debug="true">
        <appender
                name="LOGCAT"
                class="ch.qos.logback.classic.android.LogcatAppender" >
            <encoder>
                <pattern>[%method] %msg%n</pattern>
            </encoder>
        </appender>

        <property name="dest.dir" value="/sdcard/test/" />
        <appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
            <file>${dest.dir}/test.log</file>
            <append>false</append>

            <!-- #########################################
                 # Max of 2 backup zip's (plus uncompressed
                 # working file, ${dest.dir}/test.log)
                 ######################################### -->
            <rollingPolicy class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy">
                <fileNamePattern>${dest.dir}/test.%i.log.zip</fileNamePattern>
                <minIndex>1</minIndex>
                <maxIndex>2</maxIndex>
            </rollingPolicy>

            <!-- #########################################
                 # Rollover when file size reaches 5MB. 
                 # We're using our custom policy here that
                 # works around a bug (LBCORE-123).
                 ######################################### -->
            <!--<triggeringPolicy class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">-->
            <triggeringPolicy class="com.example.SizeBasedTriggeringPolicy">
                <maxFileSize>5MB</maxFileSize>
            </triggeringPolicy>
            <encoder>
                <pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
            </encoder>
        </appender>

        <logger name="com.example.HelloAndroidActivity" level="TRACE">
            <appender-ref ref="FILE" />
        </logger>

        <root level="DEBUG" >
            <appender-ref ref="LOGCAT" />
        </root>
    </configuration>
</logback>

Answer 2

May be you can use normal File apis to retrieve file length and then delete/rename it before initializing Logger if it exceeds size limit.