How do I use Microsoft Application Insights with NLog (Target cannot be found: 'ApplicationInsights')

Question

I am using Microsoft Application Insights for my Web Application. I used the Application Insights TraceListener NuGet package for logging. That worked perfectly.

Now I would like to switch to NLog. I added the Microsoft.ApplicationInsights.NLogTarget NuGet package and added a new NLog target in my NLog configuration file:

<target name='ai' xsi:type='ApplicationInsights' />

NLog throws an exception:

Target cannot be found: 'ApplicationInsights'

I also tried adding the assembly via extensions like so:

<extensions>
    <add assembly="Microsoft.ApplicationInsights.NLogTarget" />
</extensions>    

But it did not work either.

Any suggestions?

Solution 1

Solution: (thanks to @nemesv for the tip)

Programmatically add the target with

ConfigurationItemFactory.Default.Targets.RegisterDefinition(
    "ApplicationInsightsTarget", 
    typeof(Microsoft.ApplicationInsights.NLogTarget.ApplicationInsightsTarget)
);

and use it with

<target name='ai' xsi:type='ApplicationInsightsTarget' />

Solution 2

Or you can programmatically specify the target:

var config = new LoggingConfiguration();
ConfigurationItemFactory.Default.Targets.RegisterDefinition(
            "ai", 
            typeof(ApplicationInsightsTarget)
        );
ApplicationInsightsTarget aiTarget = new ApplicationInsightsTarget();
aiTarget.InstrumentationKey = "your_key";
aiTarget.Name = "ai";
config.AddTarget("ai", aiTarget);
LogManager.Configuration = config;

Comments

[Bargitta]

seems they all map to trace in application insight, any idea how to map it to exception?

[mdzieg]

What a nonsense! Documentation says nothing about that extra RegisterDefinition call. I was struggling with this as well. Thank you very much for this solution!

[Arjun Menon]

I am trying to register and log programmatically. But the logs are not getting logged. I have raised a question in stackoverflow and its up for a toss. I tried with internal log and it is showing no error what so error. Here's the link to my question stackoverflow.com/questions/60401441/…