Logging To Logentries from AppHarbor using Log4net

Simple Usage Example

public class HomeController : Controller
{
    private static readonly log4net.ILog log = log4net.LogManager.GetLogger(typeof(HomeController).Name);
    
    public ActionResult Index()
    {
        log.Debug("Home page opened");
        
        ViewBag.Message = "Welcome to ASP.NET MVC!";
        
        log.Warn("This is a warning message");
        
        return View();
    }

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

To configure Log4Net, you will need to perform the following:

* (1) Create a Logentries Account.
* (2) Setup Log4Net (if you are not already using it).
* (3) Configure the Logentries Log4Net 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. Scroll down for instructions on setting up a logfile for HTTP PUT logging.

Logentries Log4net Plugin Setup

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

The package is found at https://nuget.org/List/Packages/le_log4net

This will also install Log4Net into your project if it is not already installed.

If you wish to install it manually, you can find LeLog4net.dll in the downloads tab for this repo.

If using this option, please make sure to install Log4Net appropriately.

Log4Net 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 Log4Net along with the plug-in, paste the following into your Web/App.config directly underneath the opening <configuration>

<configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
<log4net>
  <appender name="LogentriesAppender" type="log4net.Appender.LogentriesAppender, LeLog4net">
    <Debug value="true" />
    <HttpPut value="false" />
    <Ssl value="false" />
    <layout type="log4net.Layout.PatternLayout">
      <param name="ConversionPattern" value="%d{ddd MMM dd HH:mm:ss zzz yyyy} %logger %: %level%, %m, " />
    </layout>
  </appender>
  <root>
    <level value="ALL" />
    <appender-ref ref="LogentriesAppender" />
  </root>
</log4net>

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.

AssemblyInfo.cs

Finally place the following line in your AssemblyInfo.cs file as log4net needs to be explicitly told what the config file is called:

For Web apps:

[assembly: log4net.Config.XmlConfigurator(ConfigFile="Web.config",Watch=true)]

For Console apps:

[assembly: log4net.Config.XmlConfigurator(ConfigFile="App.config",Watch=true)]

Token-Based Logging

Our default method of sending logs to Logentries is via Token TCP over port 10000. To use this, create a new logfile in the Logentries UI, and select Token TCP as the source type.

Then paste the token that is printed beside the logfile in the appSettings section of your web/app.config file for LOGENTRIES_TOKEN.

HTTP PUT Logging

Older versions of this library used HTTP PUT over port 80, which is still supported. To use this, create a new logfile in the Logentries UI, and select api/HTTP PUT as the source type.

Next, change the httpPut parameter in the above snippet to true. HTTP PUT requires two parameters called LOGENTRIES_ACCOUNT_KEY and LOGENTRIES_LOCATION in your appSettings to be set.

You can obtain your account key, by Selecting Account on the left sidebar when logged in and clicking Account Key.

Your LOGENTRIES_LOCATION parameter is the name of your host followed by the name of your logfile in the following format: "hostName/logName"

SSL/TLS

This library supports SSL/TLS logging over both the above logging methods by setting the Ssl value to true in the appender definition. This may have a performance impact however.

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 directives at the top if not already there:

using log4net;

Then create this object at class-level:

private static readonly ILog log = LogManager.GetLogger(typeof(your_class_name_here).Name);

Be sure to enter the name of current class in the indicated brackets above.

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 log4net 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 log4net's internal logger. This is enabled in your web/app.config by default and can be disabled by changing the log4net.Internal.Debug in the <appSettings> section to false. If you would like to keep log4net debug enabled, but disable Logentries debug messages, then change the debug parameter inside the <log4net> section to false.

You can also download a hello world sample app from the Downloads section. It is ready to go and only needs LOGENTRIES_TOKEN to be entered into the Web/App.config.

Ensure that you followed the section of this readme regarding your AssemblyInfo.cs file.

The Logentries appender communicates with the Logentries system using a background thread and streams the logs as they come in to the server. Because of this nature, when an application is shutting down, it is possible that any logs messages created will not have time to be posted to Logentries before the application domain is shut down.

To work around that problem, consider the following code, which will block for a moment allow LE to finish its logging. The method returns true or false depending if the queues are empty.

public void Application_End()
{
   //this will give 5 seconds for the LE background thread to finish logging to Logentries' server.
   log4net.Appenders.LogentriesAppender.AreAllQueuesEmpty(TimeSpan.FromSeconds(5));
}