log4net smtpappender subject based on log level

Question

Is it possible to configure log4net to have two smtp appenders - one that sends emails only when log level is >= WARN and second that sends everything, but never two on the same time.

<appender name="SmtpAppenderWarn" type="log4net.Appender.SmtpAppender">
  <to value="to@domain.com" />
  <from value="from@domain.com" />
  <subject value="Import completed with warnings / errors" />
  <smtpHost value="localhost" />
  <bufferSize value="512" />
  <lossy value="true" />
  <evaluator type="log4net.Core.LevelEvaluator">
    <threshold value="WARN"/>
  </evaluator>
  <layout type="log4net.Layout.PatternLayout">
    <conversionPattern value="%newline%date [%thread] %-5level %logger [%property{NDC}] - %message%newline%newline%newline" />
  </layout>
</appender>
<appender name="SmtpAppenderSuccess" type="log4net.Appender.SmtpAppender">
  <to value="to@domain.com" />
  <from value="from@domain.com" />
  <subject value="Import completed successfully" />
  <smtpHost value="localhost" />
  <bufferSize value="512" />      
  <layout type="log4net.Layout.PatternLayout">
    <conversionPattern value="%date %-5level %logger: %message%newline" />
  </layout>
  <filter type="log4net.Filter.LevelMatchFilter">
    <levelToMatch value="INFO" />
  </filter>      
</appender>

I my application I have:

Log.Info("Importer is starting...");
//my logic
//if warn Log.Warn("Warning...");
Log.Info("Import finished");

So I'm using INFO all the time. Now when I encounter WARN both messages are being sent. I wish of course that the one with success info was not sent.

score 1 · Answer 1 · edited Oct 25 '13 at 10:11

I have solved the problem by overriding log4net SendBuffer method:

namespace MyProject
{
    public class SmtpAppenderInfoOnly : SmtpAppender
    {
        protected override void SendBuffer(log4net.Core.LoggingEvent[] events)
        {
            foreach (var loggingEvent in events)
            {
                if (loggingEvent.Level != Level.Info)
                    return;
            }

            base.SendBuffer(events);
        }
    }
}

And then in config file:

<appender name="SmtpAppenderSuccess" type="MyProject.SmtpAppenderInfoOnly,MyDll">

That way the SendMail method will not be executed when SendBuffer is canceled.

Chris Missal · Answer 2 · 2013-12-23T15:37:30.943

0

Your appenders can have min/max values like so:

<levelMin value="INFO" />
<levelMax value="INFO" />

<levelMin value="WARN" />
<levelMax value="WARN" />

So you can use different appenders for different ranges. I believe this should work for you.

edited Dec 23 '13 at 15:37

answered Feb 06 '12 at 18:08

Chris Missal

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That will not work, because my equals and I don't want to have second one only for WARNs but also for higher levels – christof Feb 09 '12 at 13:32

log4net smtpappender subject based on log level

2 Answers2