Can't get tracing to work with Host.CreateDefaultBuilder

[ramonsmits]

I'm trying to get it to work with the Host builder and used the following as inspiration:

https://opentelemetry.io/docs/instrumentation/net/getting-started/

However, no tracing information is shown in the console.

The following discussions exists but don't seem to have a resolution.

• OpenTelemetry Not Adding Listener For ActivitySource #3669
• Using OpenTelemetry with Generic Host #3048

The mentioned solution to invoke AddHostedService later does not help.

using System.Diagnostics;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using OpenTelemetry;
using OpenTelemetry.Resources;
using OpenTelemetry.Trace;

var builder = Host.CreateDefaultBuilder(args);

builder.ConfigureServices(services =>
{
    services.AddOpenTelemetry().WithTracing(tracerProviderBuilder =>
    {
        tracerProviderBuilder
            .AddConsoleExporter()
            .AddSource(MyService.serviceName)
            .ConfigureResource(x => x.AddService(MyService.serviceName));
        //.SetResourceBuilder(ResourceBuilder.CreateDefault().AddService(serviceName: MyService.serviceName));
    });
    services.AddTransient<MyService>();
    services.AddHostedService<MyService>();
});
var host = builder.Build();
await host.RunAsync();

class MyService : IHostedService
{
    public const string serviceName = "MyCompany.MyProduct.MyService";
    static ActivitySource MyActivitySource = new ActivitySource(serviceName);
    private readonly ILogger<MyService> _logger;

    public MyService(ILogger<MyService> logger)
    {
        _logger = logger;
    }

    public async Task StartAsync(CancellationToken cancellationToken)
    {
        using var activity = MyActivitySource.StartActivity("SayHello");
        activity?.SetTag("foo", 1);
        activity?.SetTag("bar", "Hello, World!");
        activity?.SetTag("baz", new int[] { 1, 2, 3 });
        _logger.LogInformation("Doing something");
    }

    public async Task StopAsync(CancellationToken cancellationToken)
    {
        //throw new NotImplementedException();
    }
}

Packages:

    <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.4.0-rc.1" />
    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.4.0-rc.1" />
    <PackageReference Include="OpenTelemetry.Exporter.Console" Version="1.4.0-rc.1" />

[Kielek]

Please try

    services.AddOpenTelemetry().WithTracing(tracerProviderBuilder =>
    {
        /* your implementation*/
    }).StartWithHost();