[Geneva.Metrics] Add option to disable name validation

src/OpenTelemetry.Exporter.Geneva/.publicApi/net462/PublicAPI.Unshipped.txt

@@ -3,3 +3,5 @@ OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode.Drop = 0 -> OpenTelemetry
 OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode.ExportAsString = 1 -> OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode
 OpenTelemetry.Exporter.Geneva.GenevaExporterOptions.ExceptionStackExportMode.get -> OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode
 OpenTelemetry.Exporter.Geneva.GenevaExporterOptions.ExceptionStackExportMode.set -> void
+OpenTelemetry.Exporter.Geneva.GenevaMetricExporterOptions.DisableMetricNameValidation.get -> bool
+OpenTelemetry.Exporter.Geneva.GenevaMetricExporterOptions.DisableMetricNameValidation.set -> void

src/OpenTelemetry.Exporter.Geneva/.publicApi/net6.0/PublicAPI.Unshipped.txt

@@ -3,3 +3,5 @@ OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode.Drop = 0 -> OpenTelemetry
 OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode.ExportAsString = 1 -> OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode
 OpenTelemetry.Exporter.Geneva.GenevaExporterOptions.ExceptionStackExportMode.get -> OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode
 OpenTelemetry.Exporter.Geneva.GenevaExporterOptions.ExceptionStackExportMode.set -> void
+OpenTelemetry.Exporter.Geneva.GenevaMetricExporterOptions.DisableMetricNameValidation.get -> bool
+OpenTelemetry.Exporter.Geneva.GenevaMetricExporterOptions.DisableMetricNameValidation.set -> void

src/OpenTelemetry.Exporter.Geneva/.publicApi/netstandard2.0/PublicAPI.Unshipped.txt

@@ -3,3 +3,5 @@ OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode.Drop = 0 -> OpenTelemetry
 OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode.ExportAsString = 1 -> OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode
 OpenTelemetry.Exporter.Geneva.GenevaExporterOptions.ExceptionStackExportMode.get -> OpenTelemetry.Exporter.Geneva.ExceptionStackExportMode
 OpenTelemetry.Exporter.Geneva.GenevaExporterOptions.ExceptionStackExportMode.set -> void
+OpenTelemetry.Exporter.Geneva.GenevaMetricExporterOptions.DisableMetricNameValidation.get -> bool
+OpenTelemetry.Exporter.Geneva.GenevaMetricExporterOptions.DisableMetricNameValidation.set -> void

src/OpenTelemetry.Exporter.Geneva/Metrics/GenevaMetricExporter.cs

@@ -17,9 +17,11 @@
 using System;
 using System.Collections.Generic;
 using System.Globalization;
+using System.Reflection;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 using System.Text;
+using System.Text.RegularExpressions;
 using OpenTelemetry.Internal;
 using OpenTelemetry.Metrics;
 
@@ -108,6 +110,11 @@ public GenevaMetricExporter(GenevaMetricExporterOptions options)
         {
             this.fixedPayloadStartIndex = sizeof(BinaryHeader);
         }
+
+        if (options.DisableMetricNameValidation)
+        {
+            DisableOpenTelemetrySdkMetricNameValidation();
+        }
     }
 
     public override ExportResult Export(in Batch<Metric> batch)
@@ -258,6 +265,22 @@ protected override void Dispose(bool disposing)
         base.Dispose(disposing);
     }
 
+    internal static PropertyInfo GetOpenTelemetryInstrumentNameRegexProperty()
+    {
+        var meterProviderBuilderSdkType = typeof(Sdk).Assembly.GetType("OpenTelemetry.Metrics.MeterProviderBuilderSdk", throwOnError: false)
+            ?? throw new InvalidOperationException("OpenTelemetry.Metrics.MeterProviderBuilderSdk type could not be found reflectively.");
+
+        var instrumentNameRegexProperty = meterProviderBuilderSdkType.GetProperty("InstrumentNameRegex", BindingFlags.Public | BindingFlags.Static)
+            ?? throw new InvalidOperationException("OpenTelemetry.Metrics.MeterProviderBuilderSdk.InstrumentNameRegex property could not be found reflectively.");
+
+        return instrumentNameRegexProperty;
+    }
+
+    internal static void DisableOpenTelemetrySdkMetricNameValidation()
+    {
+        GetOpenTelemetryInstrumentNameRegexProperty().SetValue(null, new Regex(".*", RegexOptions.Compiled));
+    }
+
     internal unsafe ushort SerializeMetric(
         MetricEventType eventType,
         string metricName,

src/OpenTelemetry.Exporter.Geneva/Metrics/GenevaMetricExporterOptions.cs

@@ -90,4 +90,11 @@ public IReadOnlyDictionary<string, object> PrepopulatedMetricDimensions
             this._prepopulatedMetricDimensions = copy;
         }
     }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether or not OpenTelemetry SDK metric
+    /// name validation should be disabled. Default value: <see
+    /// langword="false"/>.
+    /// </summary>
+    public bool DisableMetricNameValidation { get; set; }
 }

test/OpenTelemetry.Exporter.Geneva.Tests/GenevaMetricExporterTests.cs

@@ -625,6 +625,56 @@ public void SuccessfulExportOnLinux()
         }
     }
 
+    [Theory]
+    [InlineData(true)]
+    [InlineData(false)]
+    public void DisableMetricNameValidationTest(bool disableMetricNameValidation)
+    {
+        var instrumentNameRegexProperty = GenevaMetricExporter.GetOpenTelemetryInstrumentNameRegexProperty();
+        var initialInstrumentNameRegexValue = instrumentNameRegexProperty.GetValue(null);
+        try
+        {
+            var exportedMetrics = new List<Metric>();
+
+            using var meter = new Meter(Guid.NewGuid().ToString());
+
+            using (var provider = Sdk.CreateMeterProviderBuilder()
+                .AddMeter(meter.Name)
+                .AddGenevaMetricExporter(options =>
+                {
+                    options.DisableMetricNameValidation = disableMetricNameValidation;
+                    if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+                    {
+                        options.ConnectionString = "Account=OTelMonitoringAccount;Namespace=OTelMetricNamespace";
+                    }
+                    else
+                    {
+                        var path = GenerateTempFilePath();
+                        options.ConnectionString = $"Endpoint=unix:{path};Account=OTelMonitoringAccount;Namespace=OTelMetricNamespace";
+                    }
+                })
+                .AddInMemoryExporter(exportedMetrics)
+                .Build())
+            {
+                var counter = meter.CreateCounter<int>("count/invalid");
+                counter.Add(1);
+            }
+
+            if (disableMetricNameValidation)
+            {
+                Assert.Single(exportedMetrics);
+            }
+            else
+            {
+                Assert.Empty(exportedMetrics);
+            }
+        }
+        finally
+        {
+            instrumentNameRegexProperty.SetValue(null, initialInstrumentNameRegexValue);
+        }
+    }
+
     private static string GenerateTempFilePath()
     {
         while (true)