using System.Diagnostics;
using System.Diagnostics.Metrics;
var builder = WebApplication.CreateBuilder(args); var app = builder.Build(); var probe = new TelemetryProbe();
using var source = new ActivitySource("SharpRune.WebLab"); using var meter = new Meter("SharpRune.WebLab"); var requests = meter.CreateCounter<long>("lab.quote.count");
using var activities = new ActivityListener { ShouldListenTo = s => s.Name == "SharpRune.WebLab", Sample = (ref ActivityCreationOptions<ActivityContext> _) => ActivitySamplingResult.AllDataAndRecorded, ActivityStopped = _ => probe.StopActivity() };
ActivitySource.AddActivityListener(activities);
using var measurements = new MeterListener();
measurements.InstrumentPublished = (instrument, listener) => { if (instrument.Meter.Name == "SharpRune.WebLab" && instrument.Name == "lab.quote.count") listener.EnableMeasurementEvents(instrument); };
measurements.SetMeasurementEventCallback<long>((instrument, value, tags, state) => probe.Measure(value)); measurements.Start();
app.MapGet("/quote", () => { using var activity = source.StartActivity("quote"); activity?.SetTag("lab.category", "catalog"); requests.Add(1, new KeyValuePair<string, object?>("operation", "quote")); return TypedResults.Ok(new { amount = 12.5m }); });
app.MapGet("/telemetry", () => new { activities = probe.Activities, measurements = probe.Measurements }); app.Run();
public sealed class TelemetryProbe { private int activities; private long measurements; public int Activities => Volatile.Read(ref activities); public long Measurements => Interlocked.Read(ref measurements); public void StopActivity() => Interlocked.Increment(ref activities); public void Measure(long value) => Interlocked.Add(ref measurements, value); }