Error using Chronicle Logger with Diffusion

Question

I am trying to configure chronicle logger to work with diffusion and the logs do not work. Instead it just gives the following error:

2016-08-26 15:56:26,316 main ERROR appenders contains an invalid element or attribute "appender"
2016-08-26 15:56:26,329 main ERROR Unable to locate appender "STDOUT"  for logger config “root"

This is the configuration that causes this error:

<?xml version="1.0" encoding="UTF-8"?>
<configuration packages="net.openhft.chronicle.logger,net.openhft.chronicle.logger.log4j2">
    <appenders>
    <appender name="console" class="org.apache.log4j.ConsoleAppender">
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"  value="%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n" />
        </layout>
       </appender>
    </appenders>
    <loggers>
        <root level="all">
            <appender-ref ref="STDOUT"/>
        </root>
        <logger name="net.openhft" level="warn"/>
    </loggers>
</configuration>

I copied this config from a separate project where it works so it should work. What am I doing wrong?

Thanks in advance.

Answer 1

You have copied the appender element from a project that uses log4j but diffusion uses log4j2 which does not support this element.

For it to work you can replace your config with something like this:

<?xml version="1.0" encoding="UTF-8"?>
<configuration packages="net.openhft.chronicle.logger,net.openhft.chronicle.logger.log4j2">
    <Properties>
        <Property name="diffusion.log.dir">../logs</Property>
        <Property name="log.dir">${sd:diffusion.log.dir}</Property>
        <Property name="pattern">%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
        </Property>
    </Properties>
    <appenders>
        <Console name="console">
            <PatternLayout pattern="$%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n" />
        </Console>
    </appenders>
    <loggers>
        <AsyncRoot level="warn" includeLocation="false">
            <AppenderRef ref="console" />
        </AsyncRoot>
    </loggers>
</configuration>

It is worth noting that you have only configured console logging and nothing will be written to a log file which means that if something happens to your server it would be very easy to lose your log history. For this reason I recommend that you also log to a file.

The default log4j2.xml supplied with Diffusion uses the RollingRandomAccessFile appender to write to a file and refers to that appenender in the AsyncRoot element.