Log4net custom json message in Console/FileAppender

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 :)

score 0 · Answer 1 · answered May 06 '18 at 17:20

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.

Log4net custom json message in Console/FileAppender

1 Answers1