Add User-Agent Header to gRPC Metadata (#417)

Author: torosent

CHANGELOG.md

@@ -2,9 +2,9 @@
 
 ## (Unreleased)
 
-- - Add automatic retry on gateway timeout in `GrpcDurableTaskClient.WaitForInstanceCompletionAsync` in [#412](https://github.com/microsoft/durabletask-dotnet/pull/412))
+- Add automatic retry on gateway timeout in `GrpcDurableTaskClient.WaitForInstanceCompletionAsync` in ([#412](https://github.com/microsoft/durabletask-dotnet/pull/412))
 - Add specific logging for NotFound error on worker connection by @halspang in ([#413](https://github.com/microsoft/durabletask-dotnet/pull/413))
-
+- Add user agent header to gRPC called in ([#417](https://github.com/microsoft/durabletask-dotnet/pull/417))
 
 ## v1.10.0
 

src/Client/AzureManaged/DurableTaskSchedulerClientOptions.cs

@@ -6,7 +6,7 @@
 using Azure.Identity;
 using Grpc.Core;
 using Grpc.Net.Client;
-using Grpc.Net.Client.Configuration;
+using Microsoft.DurableTask;
 
 namespace Microsoft.DurableTask;
 
@@ -96,6 +96,9 @@ this.Credential is not null
             async (context, metadata) =>
             {
                 metadata.Add("taskhub", taskHubName);
+
+                // Add user agent header with durabletask-dotnet and DLL version from util
+                metadata.Add("user-agent", $"{DurableTaskUserAgentUtil.GetUserAgent()}");
                 if (cache == null)
                 {
                     return;

src/Shared/AzureManaged/DurableTaskVersionUtil.cs

@@ -0,0 +1,31 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using System.Diagnostics;
+
+namespace Microsoft.DurableTask;
+
+/// <summary>
+/// Utility class for generating the user agent string for the Durable Task SDK.
+/// </summary>
+public static class DurableTaskUserAgentUtil
+{
+    /// <summary>
+    /// The name of the SDK used in the user agent string.
+    /// </summary>
+    const string SdkName = "durabletask-dotnet";
+
+    /// <summary>
+    /// The version of the SDK used in the user agent string.
+    /// </summary>
+    static readonly string PackageVersion = FileVersionInfo.GetVersionInfo(typeof(DurableTaskUserAgentUtil).Assembly.Location).FileVersion;
+
+    /// <summary>
+    /// Generates the user agent string for the Durable Task SDK based on a fixed name and the package version.
+    /// </summary>
+    /// <returns>The user agent string.</returns>
+    public static string GetUserAgent()
+    {
+        return $"{SdkName}/{PackageVersion?.ToString() ?? "unknown"}";
+    }
+}

src/Worker/AzureManaged/DurableTaskSchedulerWorkerOptions.cs

@@ -6,7 +6,7 @@
 using Azure.Identity;
 using Grpc.Core;
 using Grpc.Net.Client;
-using Grpc.Net.Client.Configuration;
+using Microsoft.DurableTask;
 
 namespace Microsoft.DurableTask;
 
@@ -102,6 +102,8 @@ this.Credential is not null
             async (context, metadata) =>
             {
                 metadata.Add("taskhub", taskHubName);
+                // Add user agent header with durabletask-dotnet and DLL version from util
+                metadata.Add("user-agent", $"{DurableTaskUserAgentUtil.GetUserAgent()}");
                 metadata.Add("workerid", this.WorkerId);
                 if (cache == null)
                 {