How to make a part of log4net message uppercase
Question
I'm using AdoNetAppender to log messages. I've added %property{log4net:HostName} conversion pattern to the message parameter.
<parameter>
<parameterName value="@message"/>
<dbType value="String"/>
<size value="4000"/>
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="[%property{log4net:HostName}] - %message"/>
</layout>
</parameter>
Output is like
[hostname] - foo bar.
But i want the output like
[HOSTNAME] - foo bar.
How can i make the hostname uppercase using conversion patterns?
Regards,
Cankut
Solution
The solution suggested by Ron Grabowski is extending PatternConverter.
public class HostNameToUpperConverter : PatternConverter
{
protected override void Convert(TextWriter writer, object state)
{
string hostName = (string)GlobalContext.Properties[LoggingEvent.HostNameProperty];
writer.Write(hostName.ToUpper());
}
}
usage in configuration file:
<layout type="log4net.Layout.PatternLayout">
<converter>
<name value="hostNameToUpper" />
<type value="MyApplication.HostNameToUpperConverter" />
</converter>
<conversionPattern value="[%hostNameToUpper] - %message" />
</layout>
OTHER TIPS
FWIW (maybe someone else will find this useful), NLog 2.0 (and maybe the 1.0 Refresh) has added some layout "wrappers" that allow modification of the output of a layout. See this link, towards the bottom.
Among the wrappers are uppercase, lowercase, trim whitespace, pad, and a few more. So, you could probably define a layout that specifies the fields to be included in the output and "wrap" either whole thing or part of it in the "uppercase" wrapper. I don't really know the exact syntax I do know that you can include layouts in other layouts so you could define a layout for "host name", wrap it in the "uppercase" wrapper, and then include that layout in the final layout. In pseudocode (configuration file pseudocode, not code pseudocode) (very pseudo!):
var host=${gdc:hostname}
var uhost=${uppercase=true,inner=host}
Now uhost can be included in the "real" layout:
${datetime} | ${uhost} | ${message}
Or, you might do it like this:
${datetime} | ${uppercase=true, inner=${gdc:hostname}} | ${message}
Note that I have not actually tried doing this in NLog, I am just going by what is on their website.