Logging To Logentries from AppHarbor using NLog

Simple Usage Example

public class HomeController : Controller
{
    private static readonly Logger log = LogManager.GetLogger(typeof(HomeController).Name);

    public ActionResult Index()
    {
        ViewBag.Message = "Welcome to ASP.NET MVC!";

        log.Warn("This is a warning message");

        return View();
    }

    public ActionResult About()
    {
        return View();
    }
}

A Sample Hello World App can be found in the download section. This simply requires you to enter your LOGENTRIES_TOKEN in the appSettings section of web/app.config. This is explained in more detail in the instructions below.

To configure NLog, you will need to perform the following:

* (1) Create a Logentries Account.
* (2) Setup NLog (if you are not already using it).
* (3) Configure the Logentries NLog plugin.

Create your Logentries Account

You can register your account on Logentries simply by clicking Sign Up at the top of the screen. Once logged in, create a new host with a name that best represents your app. Select this host and create a new logfile of source type TOKEN TCP with a name that represents what you will be logging, these names are for your own benefit.

Logentries NLog Plugin Setup

To install the Logentries Plugin Library, we suggest using Nuget.

The package is found at https://nuget.org/List/Packages/le_nlog/

This will also install NLog into your project if it is not already installed.

If you wish to install the library manually, you can find le_nlog.dll in the Downloads tab for this repo.

You will also have to install NLog yourself if you are not using our nuget.

NLog Config

In the <appSettings> section of your Web/App.config, replace LOGENTRIES_TOKEN with the token that is printed in grey beside the logfile you created in the Logentries UI.

To configure NLog along with the plug-in, paste the following into your Web/App.config directly underneath the opening <configuration>

<configSections>
  <section name="nlog" type="NLog.Config.ConfigSectionHandler, NLog"/>
</configSections>
<nlog>
  <extensions>
    <add assembly="le_nlog"/>
  </extensions>
  <targets>
    <target name="logentries" type="Logentries" debug="true"
	layout="${date:format=ddd MMM dd} ${time:format=HH:mm:ss} ${date:format=zzz yyyy} ${logger} : ${LEVEL}, ${message}"/>
  </targets>
  <rules>
    <logger name="*" minLevel="Debug" appendTo="logentries"/>
  </rules>
</nlog>

If you are using App.config in your project, you will need to set the "Copy to output Directory" property of App.config to "Copy always". This can be done inside Visual Studio.

Logging Messages

With that done, you are ready to send logs to Logentries.

In each class you wish to log from, enter the following using directive at the top if it is not already there:

using NLog;

Then create this object at class-level:

private static readonly Logger log = LogManager.GetCurrentClassLogger();

What this does is create a logger with the name of the current class for clarity in the logs.

Now within your code in that class, you can log using NLog as normal and it will log to Logentries.

Example:

log.Debug("Debugging Message");
log.Info("Informational message");
log.Warn("Warning Message");

Troubleshooting

The Logentries plugin logs its debug messages to NLog's Internal Logger, if you wish to see these change the opening <nlog> statement in web.config to:

<nlog internalLogFile="..." internalLogLevel="Debug">

Insert the location of a file on your local system to write to, ensuring that its not read-only.