Workflow api token fix (#1735)

* Changed visibility on method intended for testing only
* Fix to add API token when using AddDaprWorkflow
* Added support to use API token throughout Workflow project when communicating with runtime

---------

Signed-off-by: Whit Waldo <whit.waldo@innovian.net>

Author: WhitWaldo

src/Dapr.Workflow/DaprWorkflowClient.cs

@@ -28,15 +28,22 @@ namespace Dapr.Workflow;
 public sealed class DaprWorkflowClient : IDaprWorkflowClient
 {
     private readonly WorkflowClient _innerClient;
+    
+    /// <summary>
+    /// Exposed only for testing.
+    /// </summary>
+    internal string? DaprApiToken { get; }
 
     /// <summary>
     /// Initializes a new instance of the <see cref="DaprWorkflowClient"/> class.
     /// </summary>
     /// <param name="innerClient">The Durable Task client used to communicate with the Dapr sidecar.</param>
+    /// <param name="daprApiToken">The API token used for validating requests to Dapr.</param>
     /// <exception cref="ArgumentNullException">Thrown if <paramref name="innerClient"/> is <c>null</c>.</exception>
-    internal DaprWorkflowClient(WorkflowClient innerClient)
+    internal DaprWorkflowClient(WorkflowClient innerClient,  string? daprApiToken = null)
     {
         _innerClient = innerClient ?? throw new ArgumentNullException(nameof(innerClient));
+        DaprApiToken = daprApiToken;
     }
 
     /// <summary>

src/Dapr.Workflow/Registration/DaprWorkflowClientBuilder.cs

@@ -128,6 +128,6 @@ public override DaprWorkflowClient Build()
         }
 
         var innerClient = new WorkflowGrpcClient(grpcClient, logger, serializer);
-        return new DaprWorkflowClient(innerClient);
+        return new DaprWorkflowClient(innerClient, DaprApiToken);
     }
 }

src/Dapr.Workflow/WorkflowServiceCollectionExtensions.cs

@@ -132,7 +132,7 @@ public static DaprWorkflowBuilder AddDaprWorkflowBuilder(this IServiceCollection
     /// <param name="configure">Optional configuration for the workflow client (e.g., setting gRPC/HTTP endpoints).</param>
     /// <param name="lifetime">The lifetime of the registered services.</param>
     /// <returns>A builder for additional workflow configuration.</returns>
-    public static DaprWorkflowBuilder AddDaprWorkflowClient(
+    internal static DaprWorkflowBuilder AddDaprWorkflowClient(
         this IServiceCollection services,
         Action<IServiceProvider, DaprWorkflowClientBuilder>? configure = null,
         ServiceLifetime lifetime = ServiceLifetime.Singleton)

test/Dapr.Workflow.Test/WorkflowServiceCollectionExtensionsTests.cs

@@ -384,6 +384,31 @@ public void AddDaprWorkflowBuilder_ShouldApplyDaprApiToken_FromEnvironmentVariab
             Environment.SetEnvironmentVariable("DAPR_API_TOKEN", originalToken);
         }
     }
+
+    [Fact]
+    public void AddDaprWorkflow_ShouldApplyDaprApiToken_FromEnvironmentVariable()
+    {
+        var originalToken = Environment.GetEnvironmentVariable("DAPR_API_TOKEN");
+
+        try
+        {
+            Environment.SetEnvironmentVariable("DAPR_API_TOKEN", "workflow-env-token");
+
+            var services = new ServiceCollection();
+            services.AddLogging(b => b.AddProvider(NullLoggerProvider.Instance));
+
+            services.AddDaprWorkflow(_ => { });
+
+            var sp = services.BuildServiceProvider();
+            var client = sp.GetRequiredService<DaprWorkflowClient>();
+
+            Assert.Equal("workflow-env-token", client.DaprApiToken);
+        }
+        finally
+        {
+            Environment.SetEnvironmentVariable("DAPR_API_TOKEN", originalToken);
+        }
+    }
 
     private sealed record SerializerDependency(string Value);