I’m writing some proof-of-concept code, a prototype to get familiar with exporting metrics using the Open Telemetry libraries. I must have omitted one detail, because I see the initialization of my MeterProvider emitted to the console, but then I don’t see any metrics which I am accumulating.

I’m using this sample as a guide: https://github.com/open-telemetry/opentelemetry-dotnet/blob/main/examples/Console/TestMetrics.cs

Here is my initialization code:

    public static MeterProvider GetMeterProvider(string service, string version, string meterName, bool consoleExporter, bool OtlpExporter)
    {
        MeterProviderBuilder mpb = Sdk.CreateMeterProviderBuilder()
            .ConfigureResource(r => r.AddService(service, null, version))
            .AddMeter(meterName); // All instruments from this meter are enabled.

        if (consoleExporter)
        {
            mpb.AddConsoleExporter((exporterOptions, metricReaderOptions) =>
            {
                exporterOptions.Targets = ConsoleExporterOutputTargets.Console;

                metricReaderOptions.PeriodicExportingMetricReaderOptions.ExportIntervalMilliseconds = 1000;
                metricReaderOptions.TemporalityPreference = MetricReaderTemporalityPreference.Delta;
            });
        }

        if (OtlpExporter)
        {
           <...snipped...>
        }

        return mpb.Build();
    }

Here’s the function call. The return value, a MeterProvider, is assigned to a class member variable, to persist for the duration of the class instance. (In the code below, the prefix m_ designates a class member variable.)

m_meterProvider = TelemetryUtils.GetMeterProvider(c_Service, c_Version, "Prototype", true, false);

And here’s what I see:

After creating the MeterProvider, I create

        m_meter = new Meter("Telemetry", "8.1");
        m_counter = m_meter.CreateCounter<int>("counter", "things", "A count of things");
        m_histogram = m_meter.CreateHistogram<int>("histogram");

I think that this might be my issue. I’m creating a Meter but I don’t see how this is associated with the MeterProvider? In the sample code there is a statement:

   using var provider = providerBuilder.Build();

but I’m not sure what the function of this statement. In my code, the MeterProvider, which is the output of MeterProviderBuilder.Build() is the functional return of GetMeterProvider(); this is assigned to the class member variable m_meterProvider which persists for the duration of the class. Anyway, moving on…

Here are the measurement collection statements which execute inside of my processing loop. I even threw a ForceFlush statement in there. But no joy. I don’t see anything emitted to the console. What am I missing? Thanks for your advice!

        var observableCounter = m_meter.CreateObservableGauge("gauge", () =>
        {
            return new List<Measurement<int>>()
                {
                new Measurement<int>(
                    9999999,
                    new KeyValuePair<string, object>("tag1", "value1")),
                };
        });

        m_histogram?.Record(Counter);

        m_histogram?.Record(
            Counter * 100,
            new KeyValuePair<string, object>("tag1", "value1"));

        m_counter?.Add(Counter);

        m_counter?.Add(
            Counter * 100,
            new KeyValuePair<string, object>("tag2", "value2"));

        m_meterProvider.ForceFlush();