ASP.NET Core 8 OpenTelemetry - source class / CategoryName in logger output

I have a following OpenTelemetry configuration in my ASP.NET Core 8 code (it pushes logs and metrics to Application Insights on Azure):

builder.Services
       .AddOpenTelemetry()
       .UseAzureMonitor(x => x.ConnectionString = configuration.AppIns.ConnStr)
       .ConfigureResource(builder =>
            {
                builder.Clear();
                builder
                    .AddService(serviceName: "MyService1", serviceInstanceId: Environment.MachineName);
            })
       .WithMetrics(builder => {})
       .WithTracing();

And in my classes I use logs like that:

public class MyClass1
{
    private readonly ILogger<MyClass1> _logger;

    public MyClass1(ILogger<MyClass1> logger)
    {
        // ...

        void Method() 
        {
            _logger.LogInformation("test1");
            // ...
        }
    }
}

The problem is that in logs I don't see the class name (with namespace), nor the file path where the log was logged. In other words, how to see MyClass1 in Application Insights CustomDimensions.

Since version 1.4.0-beta.1 it's possible to log the class name that has thrown an exception or create log with telemetry exporter.

Add to your csproj:

<PackageReference Include="Azure.Monitor.OpenTelemetry.Exporter" Version="1.4.0-beta.1" />

Until this feature comes into the official version, invoke in your app:

AppContext.SetSwitch("Azure.Experimental.EnableActivitySource", true);

Tracing should be configured more or less like this:

        .WithTracing(cfg => { cfg
                .AddAspNetCoreInstrumentation(opt => opt.RecordException = true)
                .AddSource("Azure.*")
                .AddAzureMonitorTraceExporter(opt => opt.ConnectionString = azureMonitorConnectionString);
        });

As a result, you will see CategoryName field under CustomDimensions in App Insights. The field will contain the name of the class that originated the log.

More info: https://github.com/Azure/azure-sdk-for-net/pull/44754