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?

Have you checked that the Microsoft.ApplicationInsights.NLogTarget.dll is correctly copied to the output folder? Have you tried to register the target from code with: `ConfigurationItemFactory.Default.Targets.RegisterDefinition("ApplicationInsightsTarget", typeof(Microsoft.ApplicationInsights.NLogTarget.ApplicationInsightsTarget));`? — nemesv, Apr 29 '14 at 18:48
I have already checked that the NLog target dll and all the depending dll's are indeed in the final bin folder. But I will try to add it programmatically as you suggested. Good idea! — Michael A. Volz aka Flynn, Apr 30 '14 at 06:44

score 10 · Accepted Answer · answered Apr 30 '14 at 06:54

10

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' />

answered Apr 30 '14 at 06:54

Michael A. Volz aka Flynn

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1

seems they all map to trace in application insight, any idea how to map it to exception? – Bargitta Dec 13 '17 at 05:25
1

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! – emdee.pro Feb 07 '19 at 19:06
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 https://stackoverflow.com/questions/60401441/application-insights-configuration-web-api – Arjun Menon Mar 18 '20 at 16:27

score 8 · Answer 2 · answered Mar 18 '16 at 11:48

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;

score 5 · Answer 3 · edited Jan 24 '23 at 01:12

If anyone else stumbles over this: The correct target type is ApplicationInsightsTarget not ApplicationInsights.

This works fine:

<extensions>
    <add assembly="Microsoft.ApplicationInsights.NLogTarget" />
</extensions>    
<targets>
    <target name="ai" xsi:type="ApplicationInsightsTarget" />
</targets>

No need to add the target by code.

See also: https://github.com/microsoft/ApplicationInsights-dotnet/tree/main/LOGGING#nlog

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

3 Answers3

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