Make ITokenCredentialProvider public

src/Aspire.Hosting.Azure.ContainerRegistry/AzureContainerRegistryHelpers.cs

@@ -7,7 +7,6 @@
 #pragma warning disable ASPIREAZURE001
 
 using Aspire.Hosting.ApplicationModel;
-using Aspire.Hosting.Azure.Provisioning.Internal;
 using Aspire.Hosting.Pipelines;
 using Microsoft.Extensions.DependencyInjection;
 

src/Aspire.Hosting.Azure/ITokenCredentialProvider.cs

@@ -0,0 +1,32 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Azure.Core;
+
+namespace Aspire.Hosting.Azure;
+
+/// <summary>
+/// Provides access to the <see cref="TokenCredential"/> that Aspire uses
+/// to authenticate against Azure when provisioning resources and calling Azure APIs.
+/// </summary>
+/// <remarks>
+/// <para>
+/// This service is registered as a singleton when Azure provisioning is enabled
+/// (e.g., by <c>AddAzureProvisioning</c>).
+/// </para>
+/// <para>
+/// Integrations and app host code can resolve this service from <see cref="System.IServiceProvider"/>
+/// to obtain a <see cref="TokenCredential"/> instance configured by Aspire's
+/// Azure provisioning options (for example, the configured tenant id and credential source).
+/// The concrete credential type returned by <see cref="TokenCredential"/> is an implementation
+/// detail and may change between releases; callers should treat the value as an opaque
+/// <see cref="TokenCredential"/>.
+/// </para>
+/// </remarks>
+public interface ITokenCredentialProvider
+{
+    /// <summary>
+    /// Gets the <see cref="TokenCredential"/> to use for Azure authentication.
+    /// </summary>
+    TokenCredential TokenCredential { get; }
+}

src/Aspire.Hosting.Azure/Provisioning/Internal/IProvisioningServices.cs

@@ -244,14 +244,3 @@ internal interface IUserPrincipalProvider
     /// </summary>
     Task<UserPrincipal> GetUserPrincipalAsync(CancellationToken cancellationToken = default);
 }
-
-/// <summary>
-/// Provides access to Azure token credentials.
-/// </summary>
-internal interface ITokenCredentialProvider
-{
-    /// <summary>
-    /// Gets the token credential for Azure authentication.
-    /// </summary>
-    TokenCredential TokenCredential { get; }
-}

src/Aspire.Hosting.Foundry/PromptAgent/AzurePromptAgentResource.cs

@@ -6,7 +6,6 @@
 using System.Globalization;
 using Aspire.Hosting.ApplicationModel;
 using Aspire.Hosting.Azure;
-using Aspire.Hosting.Azure.Provisioning.Internal;
 using Aspire.Hosting.Pipelines;
 using Aspire.Hosting.Publishing;
 using Azure.AI.Projects;

tests/Aspire.Hosting.Azure.Tests/TokenCredentialProviderTests.cs

@@ -0,0 +1,79 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Aspire.Hosting.Utils;
+using Azure.Core;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Aspire.Hosting.Azure.Tests;
+
+public class TokenCredentialProviderTests
+{
+    [Fact]
+    public void AddAzureProvisioning_RegistersITokenCredentialProvider()
+    {
+        using var builder = TestDistributedApplicationBuilder.Create();
+        builder.AddAzureProvisioning();
+
+        using var app = builder.Build();
+
+        var provider = app.Services.GetRequiredService<ITokenCredentialProvider>();
+
+        Assert.NotNull(provider);
+        Assert.NotNull(provider.TokenCredential);
+    }
+
+    [Fact]
+    public void AddAzureProvisioning_RegistersITokenCredentialProviderAsSingleton()
+    {
+        using var builder = TestDistributedApplicationBuilder.Create();
+        builder.AddAzureProvisioning();
+
+        using var app = builder.Build();
+
+        var first = app.Services.GetRequiredService<ITokenCredentialProvider>();
+        var second = app.Services.GetRequiredService<ITokenCredentialProvider>();
+
+        Assert.Same(first, second);
+        Assert.Same(first.TokenCredential, second.TokenCredential);
+    }
+
+    [Fact]
+    public void AddingAzureResource_RegistersITokenCredentialProvider()
+    {
+        // AddAzureProvisioning is invoked indirectly when an Azure resource is added.
+        using var builder = TestDistributedApplicationBuilder.Create();
+        builder.AddAzureInfrastructure("infra", _ => { });
+
+        using var app = builder.Build();
+
+        var provider = app.Services.GetRequiredService<ITokenCredentialProvider>();
+
+        Assert.NotNull(provider.TokenCredential);
+    }
+
+    [Fact]
+    public void ITokenCredentialProvider_CanBeReplacedWithCustomImplementation()
+    {
+        // External callers should be able to plug in their own credential by
+        // replacing the registered service with their own implementation.
+        var customCredential = new TestTokenCredential();
+        var customProvider = new CustomTokenCredentialProvider(customCredential);
+
+        using var builder = TestDistributedApplicationBuilder.Create();
+        builder.AddAzureProvisioning();
+        builder.Services.AddSingleton<ITokenCredentialProvider>(customProvider);
+
+        using var app = builder.Build();
+
+        var resolved = app.Services.GetRequiredService<ITokenCredentialProvider>();
+
+        Assert.Same(customProvider, resolved);
+        Assert.Same(customCredential, resolved.TokenCredential);
+    }
+
+    private sealed class CustomTokenCredentialProvider(TokenCredential credential) : ITokenCredentialProvider
+    {
+        public TokenCredential TokenCredential { get; } = credential;
+    }
+}