[SDK + Jaeger] Support loading environment variables from IConfiguration in Traces & Metrics

build/Common.props

@@ -31,10 +31,11 @@
     <MicrosoftAspNetCoreHttpFeaturesPkgVer>[2.1.1,6.0)</MicrosoftAspNetCoreHttpFeaturesPkgVer>
     <MicrosoftCodeAnalysisAnalyzersPkgVer>[3.3.3]</MicrosoftCodeAnalysisAnalyzersPkgVer>
     <MicrosoftCodeCoveragePkgVer>[17.3.0]</MicrosoftCodeCoveragePkgVer>
+    <MicrosoftExtensionsConfigurationEnvironmentVariablesPkgVer>[3.1.0,)</MicrosoftExtensionsConfigurationEnvironmentVariablesPkgVer>
     <MicrosoftExtensionsHostingAbstractionsPkgVer>[2.1.0,)</MicrosoftExtensionsHostingAbstractionsPkgVer>
     <MicrosoftExtensionsLoggingPkgVer>[3.1.0,)</MicrosoftExtensionsLoggingPkgVer>
     <MicrosoftExtensionsLoggingConfigurationPkgVer>[3.1.0,)</MicrosoftExtensionsLoggingConfigurationPkgVer>
-    <MicrosoftExtensionsOptionsPkgVer>[3.1.0,)</MicrosoftExtensionsOptionsPkgVer>
+    <MicrosoftExtensionsOptionsPkgVer>[5.0.0,)</MicrosoftExtensionsOptionsPkgVer>
     <MicrosoftNETFrameworkReferenceAssembliesPkgVer>[1.0.0,2.0)</MicrosoftNETFrameworkReferenceAssembliesPkgVer>
     <MicrosoftSourceLinkGitHubPkgVer>[1.0.0,2.0)</MicrosoftSourceLinkGitHubPkgVer>
     <OpenTracingPkgVer>[0.12.1,0.13)</OpenTracingPkgVer>

src/OpenTelemetry.Exporter.Jaeger/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+* Added support for loading environment variables from `IConfiguration` when
+  using the `AddJaegerExporter` extension
+  ([#3720](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3720))
+
 ## 1.4.0-beta.1
 
 Released 2022-Sep-29

src/OpenTelemetry.Exporter.Jaeger/JaegerExporterHelperExtensions.cs

@@ -18,6 +18,7 @@
 using System.Net.Http;
 using System.Reflection;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
 using Microsoft.Extensions.Options;
 using OpenTelemetry.Exporter;
 using OpenTelemetry.Internal;
@@ -62,10 +63,15 @@ public static TracerProviderBuilder AddJaegerExporter(
 
             name ??= Options.DefaultName;
 
-            if (configure != null)
+            builder.ConfigureServices(services =>
             {
-                builder.ConfigureServices(services => services.Configure(name, configure));
-            }
+                if (configure != null)
+                {
+                    services.Configure(name, configure);
+                }
+
+                services.TryAddSingleton<IOptionsFactory<JaegerExporterOptions>, JaegerExporterOptions.JaegerExporterOptionsFactory>();
+            });
 
             return builder.ConfigureBuilder((sp, builder) =>
             {

src/OpenTelemetry.Exporter.Jaeger/JaegerExporterOptions.cs

@@ -15,8 +15,11 @@
 // </copyright>
 
 using System;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.Net.Http;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.Options;
 using OpenTelemetry.Internal;
 using OpenTelemetry.Trace;
 
@@ -43,37 +46,63 @@ public class JaegerExporterOptions
 
         internal static readonly Func<HttpClient> DefaultHttpClientFactory = () => new HttpClient();
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="JaegerExporterOptions"/> class.
+        /// </summary>
         public JaegerExporterOptions()
+            : this(new ConfigurationBuilder().AddEnvironmentVariables().Build())
+        {
+        }
+
+        internal JaegerExporterOptions(IConfiguration configuration)
         {
-            if (EnvironmentVariableHelper.LoadString(OTelProtocolEnvVarKey, out string protocolEnvVar))
+            var protocol = configuration.GetValue<string>(OTelProtocolEnvVarKey, null);
+            if (!string.IsNullOrEmpty(protocol))
             {
-                if (JaegerExporterProtocolParser.TryParse(protocolEnvVar, out var protocol))
+                if (JaegerExporterProtocolParser.TryParse(protocol, out var parsedProtocol))
                 {
-                    this.Protocol = protocol;
+                    this.Protocol = parsedProtocol;
                 }
                 else
                 {
-                    throw new FormatException($"{OTelProtocolEnvVarKey} environment variable has an invalid value: '{protocolEnvVar}'");
+                    throw new FormatException($"{OTelProtocolEnvVarKey} environment variable has an invalid value: '{protocol}'");
                 }
             }
 
-            if (EnvironmentVariableHelper.LoadString(OTelAgentHostEnvVarKey, out string agentHostEnvVar))
+            var agentHost = configuration.GetValue<string>(OTelAgentHostEnvVarKey, null);
+            if (!string.IsNullOrEmpty(agentHost))
             {
-                this.AgentHost = agentHostEnvVar;
+                this.AgentHost = agentHost;
             }
 
-            if (EnvironmentVariableHelper.LoadNumeric(OTelAgentPortEnvVarKey, out int agentPortEnvVar))
+            var agentPort = configuration.GetValue<string>(OTelAgentPortEnvVarKey, null);
+            if (!string.IsNullOrEmpty(agentPort))
             {
-                this.AgentPort = agentPortEnvVar;
+                if (EnvironmentVariableHelper.LoadNumeric(OTelAgentPortEnvVarKey, agentPort, out int parsedAgentPort))
+                {
+                    this.AgentPort = parsedAgentPort;
+                }
             }
 
-            if (EnvironmentVariableHelper.LoadString(OTelEndpointEnvVarKey, out string endpointEnvVar)
-                && Uri.TryCreate(endpointEnvVar, UriKind.Absolute, out Uri endpoint))
+            var endpoint = configuration.GetValue<string>(OTelEndpointEnvVarKey, null);
+            if (!string.IsNullOrEmpty(endpoint))
             {
-                this.Endpoint = endpoint;
+                if (Uri.TryCreate(endpoint, UriKind.Absolute, out Uri parsedEndpoint))
+                {
+                    this.Endpoint = parsedEndpoint;
+                }
+                else
+                {
+                    throw new FormatException($"{OTelEndpointEnvVarKey} environment variable has an invalid value: '{endpoint}'");
+                }
             }
         }
 
+        /// <summary>
+        /// Gets or sets the <see cref="JaegerExportProtocol"/> to use when
+        /// communicating to Jaeger. Default value: <see
+        /// cref="JaegerExportProtocol.UdpCompactThrift"/>.
+        /// </summary>
         public JaegerExportProtocol Protocol { get; set; } = JaegerExportProtocol.UdpCompactThrift;
 
         /// <summary>
@@ -129,5 +158,25 @@ public JaegerExporterOptions()
         /// </list>
         /// </remarks>
         public Func<HttpClient> HttpClientFactory { get; set; } = DefaultHttpClientFactory;
+
+        internal sealed class JaegerExporterOptionsFactory : OptionsFactory<JaegerExporterOptions>
+        {
+            private readonly IConfiguration configuration;
+
+            public JaegerExporterOptionsFactory(
+                IConfiguration configuration,
+                IEnumerable<IConfigureOptions<JaegerExporterOptions>> setups,
+                IEnumerable<IPostConfigureOptions<JaegerExporterOptions>> postConfigures,
+                IEnumerable<IValidateOptions<JaegerExporterOptions>> validations)
+                : base(setups, postConfigures, validations)
+            {
+                Debug.Assert(configuration != null, "configuration was null");
+
+                this.configuration = configuration;
+            }
+
+            protected override JaegerExporterOptions CreateInstance(string name)
+                => new(this.configuration);
+        }
     }
 }

src/OpenTelemetry/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+* Added support for loading environment variables from `IConfiguration` when
+  using `TracerProviderBuilder` or `MeterProviderBuilder`
+  ([#3720](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3720))
+
 ## 1.4.0-beta.1
 
 Released 2022-Sep-29

src/OpenTelemetry/Internal/Builder/ProviderBuilderServiceCollectionExtensions.cs

@@ -0,0 +1,42 @@
+// <copyright file="ProviderBuilderServiceCollectionExtensions.cs" company="OpenTelemetry Authors">
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// </copyright>
+
+#nullable enable
+
+using System.Diagnostics;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+
+namespace Microsoft.Extensions.DependencyInjection;
+
+internal static class ProviderBuilderServiceCollectionExtensions
+{
+    public static IServiceCollection AddOpenTelemetryProviderBuilderServices(this IServiceCollection services)
+    {
+        Debug.Assert(services != null, "services was null");
+
+        services.AddOptions();
+
+        // Note: When using a host builder IConfiguration is automatically
+        // registered and this registration will no-op. This only runs for
+        // Sdk.Create* style or when manually creating a ServiceCollection. The
+        // point of this registration is to make IConfiguration available in
+        // those cases.
+        services!.TryAddSingleton<IConfiguration>(sp => new ConfigurationBuilder().AddEnvironmentVariables().Build());
+
+        return services!;
+    }
+}

src/OpenTelemetry/Internal/EnvironmentVariableHelper.cs

@@ -76,6 +76,25 @@ public static bool LoadNumeric(string envVarKey, out int result)
                 return false;
             }
 
+            return LoadNumeric(envVarKey, value, out result);
+        }
+
+        /// <summary>
+        /// Reads an environment variable and parses is as a
+        /// <a href="https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/sdk-environment-variables.md#numeric-value">
+        /// numeric value</a> - a non-negative decimal integer.
+        /// </summary>
+        /// <param name="envVarKey">The name of the environment variable.</param>
+        /// <param name="value">The value of the environment variable.</param>
+        /// <param name="result">The parsed value of the environment variable.</param>
+        /// <returns>
+        /// Returns <c>true</c> when a non-empty value was read; otherwise, <c>false</c>.
+        /// </returns>
+        /// <exception cref="FormatException">
+        /// Thrown when failed to parse the non-empty value.
+        /// </exception>
+        public static bool LoadNumeric(string envVarKey, string value, out int result)
+        {
             if (!int.TryParse(value, NumberStyles.None, CultureInfo.InvariantCulture, out result))
             {
                 throw new FormatException($"{envVarKey} environment variable has an invalid value: '{value}'");

src/OpenTelemetry/Metrics/Builder/MeterProviderBuilderBase.cs

@@ -52,7 +52,7 @@ internal MeterProviderBuilderBase(IServiceCollection services)
         {
             Guard.ThrowIfNull(services);
 
-            services.AddOptions();
+            services.AddOpenTelemetryProviderBuilderServices();
             services.TryAddSingleton<MeterProvider>(sp => new MeterProviderSdk(sp, ownsServiceProvider: false));
 
             this.services = services;
@@ -65,7 +65,7 @@ protected MeterProviderBuilderBase()
         {
             var services = new ServiceCollection();
 
-            services.AddOptions();
+            services.AddOpenTelemetryProviderBuilderServices();
 
             this.services = services;
             this.ownsServices = true;

src/OpenTelemetry/Metrics/Builder/MeterProviderBuilderServiceCollectionHelper.cs

@@ -42,7 +42,7 @@ internal static IServiceCollection RegisterConfigureStateCallback(
         Debug.Assert(services != null, "services was null");
         Debug.Assert(configure != null, "configure was null");
 
-        return services.AddSingleton(new ConfigureMeterProviderBuilderStateCallbackRegistration(configure!));
+        return services!.AddSingleton(new ConfigureMeterProviderBuilderStateCallbackRegistration(configure!));
     }
 
     internal static void InvokeRegisteredConfigureStateCallbacks(
@@ -52,7 +52,7 @@ internal static void InvokeRegisteredConfigureStateCallbacks(
         Debug.Assert(serviceProvider != null, "serviceProvider was null");
         Debug.Assert(state != null, "state was null");
 
-        var callbackRegistrations = serviceProvider.GetServices<ConfigureMeterProviderBuilderStateCallbackRegistration>();
+        var callbackRegistrations = serviceProvider!.GetServices<ConfigureMeterProviderBuilderStateCallbackRegistration>();
 
         foreach (var callbackRegistration in callbackRegistrations)
         {

src/OpenTelemetry/OpenTelemetry.csproj

@@ -17,8 +17,10 @@
 
   <ItemGroup>
     <PackageReference Include="System.Reflection.Emit.Lightweight" Version="$(SystemReflectionEmitLightweightPkgVer)" Condition="'$(TargetFramework)' != 'net6.0'" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="$(MicrosoftExtensionsConfigurationEnvironmentVariablesPkgVer)" />
     <PackageReference Include="Microsoft.Extensions.Logging" Version="$(MicrosoftExtensionsLoggingPkgVer)" />
     <PackageReference Include="Microsoft.Extensions.Logging.Configuration" Version="$(MicrosoftExtensionsLoggingConfigurationPkgVer)" />
+    <PackageReference Include="Microsoft.Extensions.Options" Version="$(MicrosoftExtensionsOptionsPkgVer)" />
   </ItemGroup>
 
   <ItemGroup>

src/OpenTelemetry/Trace/Builder/TracerProviderBuilderBase.cs

@@ -51,7 +51,7 @@ internal TracerProviderBuilderBase(IServiceCollection services)
         {
             Guard.ThrowIfNull(services);
 
-            services.AddOptions();
+            services.AddOpenTelemetryProviderBuilderServices();
             services.TryAddSingleton<TracerProvider>(sp => new TracerProviderSdk(sp, ownsServiceProvider: false));
 
             this.services = services;
@@ -64,7 +64,7 @@ protected TracerProviderBuilderBase()
         {
             var services = new ServiceCollection();
 
-            services.AddOptions();
+            services.AddOpenTelemetryProviderBuilderServices();
 
             this.services = services;
             this.ownsServices = true;

src/OpenTelemetry/Trace/Builder/TracerProviderBuilderServiceCollectionHelper.cs

@@ -42,7 +42,7 @@ internal static IServiceCollection RegisterConfigureStateCallback(
         Debug.Assert(services != null, "services was null");
         Debug.Assert(configure != null, "configure was null");
 
-        return services.AddSingleton(new ConfigureTracerProviderBuilderStateCallbackRegistration(configure!));
+        return services!.AddSingleton(new ConfigureTracerProviderBuilderStateCallbackRegistration(configure!));
     }
 
     internal static void InvokeRegisteredConfigureStateCallbacks(
@@ -52,7 +52,7 @@ internal static void InvokeRegisteredConfigureStateCallbacks(
         Debug.Assert(serviceProvider != null, "serviceProvider was null");
         Debug.Assert(state != null, "state was null");
 
-        var callbackRegistrations = serviceProvider.GetServices<ConfigureTracerProviderBuilderStateCallbackRegistration>();
+        var callbackRegistrations = serviceProvider!.GetServices<ConfigureTracerProviderBuilderStateCallbackRegistration>();
 
         foreach (var callbackRegistration in callbackRegistrations)
         {

test/OpenTelemetry.Exporter.Jaeger.Tests/JaegerExporterOptionsTests.cs

@@ -15,6 +15,8 @@
 // </copyright>
 
 using System;
+using System.Collections.Generic;
+using Microsoft.Extensions.Configuration;
 using Xunit;
 
 namespace OpenTelemetry.Exporter.Jaeger.Tests
@@ -93,6 +95,29 @@ public void JaegerExporterOptions_EnvironmentVariableNames()
             Assert.Equal("OTEL_EXPORTER_JAEGER_ENDPOINT", JaegerExporterOptions.OTelEndpointEnvVarKey);
         }
 
+        [Fact]
+        public void JaegerExporterOptions_FromConfigurationTest()
+        {
+            var values = new Dictionary<string, string>()
+            {
+                [JaegerExporterOptions.OTelProtocolEnvVarKey] = "http/thrift.binary",
+                [JaegerExporterOptions.OTelAgentHostEnvVarKey] = "jaeger-host",
+                [JaegerExporterOptions.OTelAgentPortEnvVarKey] = "123",
+                [JaegerExporterOptions.OTelEndpointEnvVarKey] = "http://custom-endpoint:12345",
+            };
+
+            var configuration = new ConfigurationBuilder()
+                .AddInMemoryCollection(values)
+                .Build();
+
+            var options = new JaegerExporterOptions(configuration);
+
+            Assert.Equal("jaeger-host", options.AgentHost);
+            Assert.Equal(123, options.AgentPort);
+            Assert.Equal(JaegerExportProtocol.HttpBinaryThrift, options.Protocol);
+            Assert.Equal(new Uri("http://custom-endpoint:12345"), options.Endpoint);
+        }
+
         private static void ClearEnvVars()
         {
             Environment.SetEnvironmentVariable(JaegerExporterOptions.OTelProtocolEnvVarKey, null);