Automatically add a tag for all Application Insights telemetry from .Net Applications

Question

We have several .Net 5 projects / applications that are logically grouped together and I'd like to globally apply a tag to each telemetry sent from each application depending on its logical group identifier into a specific tag.

Is there any way to do this on a per-project level and if so, how?

Answer 1

You can add a TelemetryInitializer similar to this:

internal class MyTelemetryInitializer : ITelemetryInitializer
{
    public void Initialize(ITelemetry telemetry)
    {           
        telemetry.Context.GlobalProperties.Add("mytagname", "mytagvalue");
    }
}

Register it:

using Microsoft.ApplicationInsights.Extensibility;
using CustomInitializer.Telemetry;
public void ConfigureServices(IServiceCollection services)
{
    services.AddSingleton<ITelemetryInitializer, MyTelemetryInitializer>();
}

This will ensure that every telemetry item emitted by this app will have above tag.