SQL Logging with log4net & ASP.NET MVC

I wanted to get some logging action on my latest project and I’ve heard a lot about log4net so I thought I’d give it a whirl. My goal was to have a simple interface that implements log4net and writes to SQL Server. With that said, my interface ended up looking like this:

public interface ILoggingService    

{        

void Log(string message);    

}

I told you it was simple :)

Okay, now let’s go ahead and implement the ILoggingService like this:

public class LoggingService : ILoggingService

    {

        private static readonly ILog log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

        public void Log(string message)

        {

            log.Info(message);

        }

    }

This particular implementation is only going to log informational type things and not errors or warnings. Basically I want it for auditing purposes. Note: LogManager is part of log4net.

So let’s go on and configure log4net. First we’ll create an IStartUpTask, see this post for more info on the IStartUpTask.

    public class log4netConfigurator : IStartUpTask

    {

        public void Configure()

        {

            log4net.Config.XmlConfigurator.Configure(); 

        }

    }

I’m going to configure log4net in my web.config. I’ve seen a lot of people have a separate log4net.config file, but I want to just put mine in the web.config. So let’s add a log4net section to the <configSections> like this:

<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,Log4net"/>

Now we can add the section to the web.config like this:

<log4net>

  <root>

   <level value="ALL"/>

   <appender-ref ref="ADONetAppender"/>

  </root>

  <appender name="ADONetAppender" type="log4net.Appender.ADONetAppender">

   <bufferSize value="1"/>

   <connectionType value="System.Data.SqlClient.SqlConnection, System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/>

   <connectionString value="server=serverNAME; uid=userNAME; pwd=passWORD; database=databaseNAME"/>

   <commandText value="INSERT INTO ChangePasswordLog ([Date],[Thread],[Level],[Logger],[Message],[Exception]) VALUES (@log_date, @thread, @log_level, @logger, @message, @exception)"/>

   <parameter>

    <parameterName value="@log_date"/>

    <dbType value="DateTime"/>

    <layout type="log4net.Layout.RawTimeStampLayout"/>

   </parameter>

   <parameter>

    <parameterName value="@thread"/>

    <dbType value="String"/>

    <size value="255"/>

    <layout type="log4net.Layout.PatternLayout">

     <conversionPattern value="%thread"/>

    </layout>

   </parameter>

   <parameter>

    <parameterName value="@log_level"/>

    <dbType value="String"/>

    <size value="50"/>

    <layout type="log4net.Layout.PatternLayout">

     <conversionPattern value="%level"/>

    </layout>

   </parameter>

   <parameter>

    <parameterName value="@logger"/>

    <dbType value="String"/>

    <size value="255"/>

    <layout type="log4net.Layout.PatternLayout">

     <conversionPattern value="%logger"/>

    </layout>

   </parameter>

   <parameter>

    <parameterName value="@message"/>

    <dbType value="String"/>

    <size value="4000"/>

    <layout type="log4net.Layout.PatternLayout">

     <conversionPattern value="%message"/>

    </layout>

   </parameter>

   <parameter>

    <parameterName value="@exception"/>

    <dbType value="String"/>

    <size value="2000"/>

    <layout type="log4net.Layout.ExceptionLayout"/>

   </parameter>

  </appender>

 </log4net>

Okay, so I have an appender setup here to write to my DB.I think it’s pretty self explanatory, if you disagree, post me a comment and I’ll go into more detail. One hiccup I ran into was the bufferSize because I kept trying to test to see if it was writing to my DB and nothing was showing up. The reason being…I didn’t have 100 log entries. I changed the bufferSize to 1 and POOF my record showed up :)

So now in my controller, I accept an ILoggingService in the constructor like this:

        private readonly ILoggingService _loggingService;

        public HomeController(ILoggingService loggingService)

        {

            _loggingService = loggingService;

        }

So now I can call my Log method from any of my actions like this:

var changePasswordService = DI.ChangePasswordService(username);

changePasswordService.ChangePassword(form.ValidationToken, form.Password);

_loggingService.Log("Password changed for user " + username);

All done! Now I have logging in my app.

Thanks for reading!