OTEL_TRACES_SAMPLER and OTEL_TRACES_SAMPLER_ARG are handled by SDK

src/OpenTelemetry.AutoInstrumentation/Configurations/ConfigurationKeys.cs

@@ -103,16 +103,6 @@ public static class Traces
         /// </summary>
         public const string AdditionalLegacySources = "OTEL_DOTNET_AUTO_TRACES_ADDITIONAL_LEGACY_SOURCES";
 
-        /// <summary>
-        /// Configuration key for sampler to be used for traces.
-        /// </summary>
-        public const string TracesSampler = "OTEL_TRACES_SAMPLER";
-
-        /// <summary>
-        /// Configuration key for string value to be used as the sampler argument.
-        /// </summary>
-        public const string TracesSamplerArguments = "OTEL_TRACES_SAMPLER_ARG";
-
         /// <summary>
         /// Configuration keys for instrumentation options.
         /// </summary>

src/OpenTelemetry.AutoInstrumentation/Configurations/EnvironmentConfigurationTracerHelper.cs

@@ -58,7 +58,6 @@ public static TracerProviderBuilder UseEnvironmentVariables(
         }
 
         builder
-            .SetSampler(settings)
             // Exporters can cause dependency loads.
             // Should be called later if dependency listeners are already setup.
             .SetExporter(settings, pluginManager)
@@ -89,23 +88,6 @@ private static TracerProviderBuilder AddWcfIfNeeded(
         return tracerProviderBuilder;
     }
 
-    private static TracerProviderBuilder SetSampler(this TracerProviderBuilder builder, TracerSettings settings)
-    {
-        if (settings.TracesSampler == null)
-        {
-            return builder;
-        }
-
-        var sampler = TracerSamplerHelper.GetSampler(settings.TracesSampler, settings.TracesSamplerArguments);
-
-        if (sampler == null)
-        {
-            return builder;
-        }
-
-        return builder.SetSampler(sampler);
-    }
-
     private static TracerProviderBuilder SetExporter(this TracerProviderBuilder builder, TracerSettings settings, PluginManager pluginManager)
     {
         if (settings.ConsoleExporterEnabled)

src/OpenTelemetry.AutoInstrumentation/Configurations/TracerSettings.cs

@@ -52,16 +52,6 @@ internal class TracerSettings : Settings
     /// </summary>
     public InstrumentationOptions InstrumentationOptions { get; private set; } = new(new Configuration(failFast: false));
 
-    /// <summary>
-    /// Gets sampler to be used for traces.
-    /// </summary>
-    public string? TracesSampler { get; private set; }
-
-    /// <summary>
-    /// Gets a value to be used as the sampler argument.
-    /// </summary>
-    public string? TracesSamplerArguments { get; private set; }
-
     protected override void OnLoad(Configuration configuration)
     {
         TracesExporter = ParseTracesExporter(configuration);
@@ -97,9 +87,6 @@ protected override void OnLoad(Configuration configuration)
         OpenTracingEnabled = configuration.GetBool(ConfigurationKeys.Traces.OpenTracingEnabled) ?? false;
 
         InstrumentationOptions = new InstrumentationOptions(configuration);
-
-        TracesSampler = configuration.GetString(ConfigurationKeys.Traces.TracesSampler);
-        TracesSamplerArguments = configuration.GetString(ConfigurationKeys.Traces.TracesSamplerArguments);
     }
 
     private static TracesExporter ParseTracesExporter(Configuration configuration)

test/OpenTelemetry.AutoInstrumentation.Tests/Configurations/SettingsTests.cs

@@ -53,8 +53,6 @@ internal void TracerSettings_DefaultValues()
             settings.EnabledInstrumentations.Should().NotBeEmpty();
             settings.ActivitySources.Should().BeEquivalentTo(new List<string> { "OpenTelemetry.AutoInstrumentation.*" });
             settings.AdditionalLegacySources.Should().BeEmpty();
-            settings.TracesSampler.Should().BeNull();
-            settings.TracesSamplerArguments.Should().BeNull();
 
             // Instrumentation options tests
             settings.InstrumentationOptions.GraphQLSetDocument.Should().BeFalse();
@@ -252,21 +250,6 @@ internal void TracerSettings_Instrumentations_SupportedValues(string tracerInstr
         settings.EnabledInstrumentations.Should().BeEquivalentTo(new List<TracerInstrumentation> { expectedTracerInstrumentation });
     }
 
-    [Fact]
-    internal void TracerSettings_TracerSampler()
-    {
-        const string expectedTracesSampler = nameof(expectedTracesSampler);
-        const string expectedTracesSamplerArguments = nameof(expectedTracesSamplerArguments);
-
-        Environment.SetEnvironmentVariable(ConfigurationKeys.Traces.TracesSampler, expectedTracesSampler);
-        Environment.SetEnvironmentVariable(ConfigurationKeys.Traces.TracesSamplerArguments, expectedTracesSamplerArguments);
-
-        var settings = Settings.FromDefaultSources<TracerSettings>(false);
-
-        settings.TracesSampler.Should().Be(expectedTracesSampler);
-        settings.TracesSamplerArguments.Should().Be(expectedTracesSamplerArguments);
-    }
-
     [Theory]
 #if NETFRAMEWORK
     [InlineData("ASPNET", MetricInstrumentation.AspNet)]
@@ -384,8 +367,6 @@ private static void ClearEnvVars()
         }
 
         Environment.SetEnvironmentVariable(ConfigurationKeys.Traces.Exporter, null);
-        Environment.SetEnvironmentVariable(ConfigurationKeys.Traces.TracesSampler, null);
-        Environment.SetEnvironmentVariable(ConfigurationKeys.Traces.TracesSamplerArguments, null);
         Environment.SetEnvironmentVariable(ConfigurationKeys.Traces.InstrumentationOptions.GraphQLSetDocument, null);
         Environment.SetEnvironmentVariable(ConfigurationKeys.ExporterOtlpProtocol, null);
         Environment.SetEnvironmentVariable(ConfigurationKeys.FlushOnUnhandledException, null);