Log4 6

The short answer is… yes. Log4Net targets .Internet Standard, which gives it a level of compatibility across the entirety of .NET core, including .Cyberspace 6.

But it’s worth asking another question: exercise y’all
want
to employ Log4Net on .NET six? Here, we will review two ways to get Log4Net running on .Net vi using the new hosting model, and then discuss whether Log4Net is the correct logging framework for most developers.

• Using Log4Net on .Cyberspace 6 (proof-of-concept examples)
• Is Log4Net a Good Choice for .Cyberspace Cadre/.Cyberspace 6?

But Beginning, What is Log4Net?

Log4Net is a .NET logging framework maintained by Apache, based on their popular Coffee logging framework Log4j.

Traditionally, Log4Net was i of the easiest ways to start logging to a file, database, or even an email on .NET Framework. Over time, it has fallen out of favor compared to logging frameworks like Serilog and NLog, which have more advanced features like structured logging.

If you’re not familiar with Log4Net, sympathize it’due south
a bit of a legacy choice. Even and so, it nevertheless has a decent number of users and was one of the better logging frameworks effectually for a long fourth dimension. It’s worth at least a discussion.

Using Log4Net on .NET 6

If you like Log4Net equally a way to output log statements to text files, databases, and more than, it tin still do this on .Cyberspace half-dozen. You just need to make sure to use a version of Log4Net that targets .NET Standard (two.0.7 and beyond). In fact, I can use Log4Net alongside the default logging API for .NET Core: Microsoft.Extensions.Logging.

Log4Net every bit a MEL provider

On ASP.NET Cadre, I tin can use Log4Net as a Microsoft.Extensions.Logging (MEL) provider, which and then writes logs to the desired appender (i.e., log sink, Log4Net refers to them every bit appenders). In general, we recommend using MEL as the logging API for nigh .Cyberspace Cadre projects. It’s extremely flexible and allows for a very make clean logging architecture.

The Microsoft.Extensions.Logging.Log4Net.AspNetCore package is written and maintained past Ángel García Santos (huorswords) and possibly the easiest log-to-file provider for MEL to set up. Just create a log4net.config file with a log file every bit an appender, then add two using statements and a single line of code to the new .NET 6 hosting model:

            
              //Plan.cs
              
              using
              Microsoft.Extensions.Logging
              ;
              using
              Microsoft.Extensions.Logging.Log4Net.AspNetCore
              ;
              var
              builder
              =
              WebApplication
              .
              CreateBuilder
              (
              args
              );
              builder
              .
              Logging
              .
              AddLog4Net
              ();
              //creating the provider //...
              
            
          

So I added a simple exam log to the privacy page:

            
              //Privacy.cshtml.cs //...
              
              public
              PrivacyModel
              (
              ILogger
              <
              PrivacyModel
              >
              logger
              )
              {
              _logger
              =
              logger
              ;
              logger
              .
              LogWarning
              (
              "This is a MEL alert on the privacy page"
              );
              }
              //...
              
            
          

And ran the application to create the following log file:

Recently, I wrote an commodity with ii file logging examples using Serilog and NLog as the providers. While I really like those options (and ultimately retrieve they’re better for .Net Core projects), the Log4Net package was slightly faster to prepare. Not bad!

Just I don’t think this technique is the answer everyone is looking for. I’d imagine a more mutual scenario is trying to migrate an existing .NET Framework application that uses Log4Net to .Internet Core/.Cyberspace half dozen while trying to avoid major changes to your logging. Using Log4Net every bit the provider really only solves one-half of the problem. Certain, it volition let for you to use Log4Net pointing to the same appender (text file, console, etc.), but it may crave a significant corporeality of editing to get working correct (i.e., a lot of dependency injection).

Using Log4Net without MEL

Log4Net can work on .Internet 6 without using MEL. This means, in theory, you can drift.Cyberspace Framework applications and keep the aforementioned Log4Net logging statements. Whether it’southward advisable is a dissever question. For now, let’s merely get over a proof-of-concept instance that shows Log4Net operating on its own on .Cyberspace half dozen.

For the template ASP.Net awarding using the new hosting model, all I had to do was add one line to grab the config file (located in the root directory):

            
              //Program.cs
              
              using
              log4net.Config
              ;
              var
              builder
              =
              WebApplication
              .
              CreateBuilder
              (
              args
              );
              XmlConfigurator
              .
              Configure
              (
              new
              FileInfo
              (
              "log4net.config"
              ));
              //...
              
            
          

So I could log throughout the awarding using the
ILog
interface as you would with Log4Net on .Internet Framework. Allow’s wait at the equivalent privacy page log I wrote to MEL, but writing to Log4Net directly instead:

            
              //Privacy.cshtml.cs //...
              
              public
              void
              OnGet
              ()
              {
              ILog
              log
              =
              LogManager
              .
              GetLogger
              (
              typeof
              (
              Program
              ));
              log
              .
              Warn
              (
              "This is a Log4Net warning on the privacy page"
              );
              }
              //..
              
            
          

The resulting log file was well-nigh identical to the MEL Provider example, minus the additional host logs captured by MEL:

All this to say, this isn’t an example of platonic logging for a .NET half dozen/.NET Cadre application, just a demonstration that Log4Net actually works on the platform. Only let’south talk over whether you
should
use Log4Net.

Is Log4Net a Good Choice for .Net Core/.NET 6?

If you are making an application from scratch, I would not recommend using Log4Net. While information technology’southward quick to set up, there are many aspects of Log4Net that are less than ideal:

• It’due south challenging to detect .Internet Cadre documentation.
  Nearly of the official documentation is written for .NET Framework. This is non necessarily a bad thing, every bit most Log4Net applications
  are congenital with
  .NET Framework. Simply for Serilog, NLog, Loupe, etc., it’s pretty easy to detect official .NET Core documentation.

• Many Log4Net features are missing for the .Internet Cadre implementations.
  Appenders (sinks) such every bit the colored console don’t work. Stack trace patterns are unsupported, and more features are missing. The .NET Core offer is just simply worse.

• Log4Net merely doesn’t have the capabilities of modern frameworks.
  Information technology doesn’t support structured logging well, it focuses on XML configuration (technically, there are other config options, merely they are not well documented), and the current development is focused on exclusively life support. Stock Log4Net lacks features similar structured logging or client-side logging for ASP.Cyberspace applications.

Instead, start with MEL and try out different providers similar Serilog for logging to a file or Loupe for detailed centralized logging (highly recommended ). Using MEL saves you time in the future, every bit it is compatible with pretty much whatever logging framework or sink yous would want to use. Changing from one logging platform to another is as simple every bit configuring a new provider; no rewriting is required for the log statements.

What Nearly for Applications Migrating from .Internet Framework to .NET half-dozen?

This is bluntly a topic that deserves its own article, just it would be a disservice non to discuss information technology in any capacity. A big portion of Log4Net users are in this exact scenario.

In short,
everything that makes Log4Net unappealing for new applications is true for migrating applications. But it’due south more hard to justify a new logging framework when you already have 1 in place. Log4Net even so works, then you’re not
required
to switch.

That being said, migration is oft the right time to change your logging. Here are a few things to consider when deciding whether to motion on from Log4Net or non:

• Migration can change what’s needed from your logs. New features and possibilities can pb to farther information requirements that your current logging system does not meet. For example, .NET Core/.NET six offers cantankerous-platform support, cluster-based application deployment, improved performance, and more compared to .Cyberspace Framework. If you lot’re planning on extending platform support or using a more circuitous linux cluster deployment, a logging arrangement congenital for a single Windows server would require pregnant changes anyway.

• Log4Net isn’t going to go much better for .NET Core/.NET vi. Just because information technology works well plenty now doesn’t mean it will piece of work well enough in the future, when documentation is harder to find and your average developer is less familiar with information technology. The longer you stick to any legacy applied science, the greater the price is in the time to come to maintain or move on from that engineering. Switching the logging framework now tin can save fourth dimension and money after.

• The amount of labor required to switch will vary from project to project. Not every awarding has a behemothic codebase with thousands of unique logging statements. If your awarding has ten unique logging statements, rewriting to another logging framework may not take too much fourth dimension or effort (peculiarly if yous tin can merely copy over a few log classes to MEL and go out logging statements largely untouched). Another factor on the required labor is the number of third political party libraries/plugins used with Log4Net. Some of those may work with .NET Cadre, and some may not. Fixing or replacing those will need labor too.

But information technology’s much easier for me to say “don’t utilize Log4Net” than for someone to rewrite every logging statement in their application. The realities of software development often event in not using the best technologies all the fourth dimension.

If you lot tin’t move abroad from Log4Net before migrating, it’due south not the stop of the world. It withal works in a decent number of scenarios, even if non optimal.

Log4Net Still Works on .Net 6, But Information technology’s Not the Best Option

Log4Net has been a stable selection for logging on .Net, and still is. It was super easy to go working equally a MEL provider and on its ain. Ease of use will always have appeal. Just other frameworks like Serilog, Nlog, and the Loupe framework are easy to fix up as well, with better documentation, characteristic sets, and more active development. So we recommend switching to a different framework if at all feasible.

If you want to change your logging for .Cyberspace 6, consider trying Loupe!

Loupe can exist used every bit a MEL provider, on its own, or every bit a log sink for other .NET Core frameworks like Serilog. Yous can get started with Loupe in any of these capacities using our gratis local log viewer in the link below.