Log4net custom json message in Console/FileAppender - log4net

Question

I need to log with log4net into multiple targets (loggly, console, file). For loggly I need to log in JSON for some metadata to find logs. I am altering the messageobject for this by adding the metadata to the dynamic messageobject like this (example subject).
public void Info(string message)
{
log.Info(GetLogObject(message));
}
private object GetLogObject(string message, Exception ex = null)
{
dynamic obj = new ExpandoObject();
obj.message = message;
obj.exception = ex;
obj.subject = _configuration.SubjectId;
return obj;
}
app.config
<log4net>
<root>
<level value="ALL" />
<appender-ref ref="ConsoleAppender" />
<appender-ref ref="RollingFileAppender" />
<appender-ref ref="LogglyAppender" />
</root>
<appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date - %message%newline" />
</layout>
</appender>
<appender name="LogglyAppender" type="log4net.loggly.LogglyAppender, log4net-loggly">
<rootUrl value="https://logs-01.loggly.com/" />
<inputKey value="*" />
<tag value="AppTag" />
<filter type="log4net.Filter.LevelRangeFilter">
<levelMin value="ERROR" />
<levelMax value="FATAL" />
</filter>
</appender>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="Logs/rolling.log" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="5" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %level - %message%newline" />
</layout>
</appender>
Now the Console and FileAppenders are logging JSON as this:
2017-06-12 15:28:10,236 INFO - {[message, Will collect every 1 Hours, 0 Minutes and 0 Seconds], [exception, ], [subject, 11111111-1111-1111-1111-111111111111]}
2017-06-12 15:28:10,271 INFO - {[message, Collection Round started at 12.06.2017 13:28:10], [exception, ], [subject, 11111111-1111-1111-1111-111111111111]}
I want these appenders just to log the message itself (obj.message) to look like this:
2017-06-12 15:28:10,236 INFO - Will collect every 1 Hours, 0 Minutes and 0 Seconds
2017-06-12 15:28:10,271 INFO - Collection Round started at 12.06.2017 11:17:29
How can I do this?
Thank you very much :)

Answer 1

What would happen if you created your own type for the message object (instead of using a dynamic object), and override the ToString() method? I suspect, LogglyAppender would render the graph while the regular PatternLayout would resort to ToString(). I haven't tried this, just a hint. You could perhaps subclass the ExpandoObject not to loose that dynamicity.