Add test meter to stress app with meter and instrument tags (#5046)

playground/Stress/Stress.ApiService/Program.cs

@@ -12,14 +12,23 @@
 builder.AddServiceDefaults();
 
 builder.Services.AddOpenTelemetry()
-    .WithTracing(tracing => tracing.AddSource(TraceCreator.ActivitySourceName, ProducerConsumer.ActivitySourceName));
+    .WithTracing(tracing => tracing.AddSource(TraceCreator.ActivitySourceName, ProducerConsumer.ActivitySourceName))
+    .WithMetrics(metrics => metrics.AddMeter(TestMetrics.MeterName));
+builder.Services.AddSingleton<TestMetrics>();
 
 var app = builder.Build();
 
 app.Lifetime.ApplicationStarted.Register(ConsoleStresser.Stress);
 
 app.MapGet("/", () => "Hello world");
 
+app.MapGet("/increment-counter", (TestMetrics metrics) =>
+{
+    metrics.IncrementCounter(1, new TagList([new KeyValuePair<string, object?>("add-tag", "1")]));
+
+    return "Big trace created";
+});
+
 app.MapGet("/big-trace", async () =>
 {
     var bigTraceCreator = new TraceCreator();

playground/Stress/Stress.ApiService/TestMetrics.cs

@@ -0,0 +1,38 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Diagnostics;
+using System.Diagnostics.Metrics;
+
+namespace Stress.ApiService;
+
+public class TestMetrics : IDisposable
+{
+    public const string MeterName = "TestMeter";
+
+    private readonly Meter _meter;
+    private readonly Counter<int> _counter;
+
+    public TestMetrics()
+    {
+        _meter = new Meter(MeterName, "1.0.0", new[]
+        {
+            new KeyValuePair<string, object?>("meter-tag", Guid.NewGuid().ToString())
+        });
+
+        _counter = _meter.CreateCounter<int>("test-counter", unit: null, description: null, tags: new[]
+        {
+            new KeyValuePair<string, object?>("instrument-tag", Guid.NewGuid().ToString())
+        });
+    }
+
+    public void IncrementCounter(int value, in TagList tags)
+    {
+        _counter.Add(value, in tags);
+    }
+
+    public void Dispose()
+    {
+        _meter.Dispose();
+    }
+}