add target framework to error

src/WebJobs.Extensions.DurableTask/DurableTaskExtension.cs

@@ -32,6 +32,10 @@
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 
+// debugging
+using System.Reflection;
+using System.Runtime.Versioning;
+
 namespace Microsoft.Azure.WebJobs.Extensions.DurableTask
 {
     /// <summary>
@@ -447,10 +451,15 @@ void IExtensionConfigProvider.Initialize(ExtensionConfigContext context)
                 this.taskHubWorker.AddOrchestrationDispatcherMiddleware(ooprocMiddleware.CallOrchestratorAsync);
                 this.taskHubWorker.AddEntityDispatcherMiddleware(ooprocMiddleware.CallEntityAsync);
 #else
+
+                var targetFramework = Assembly.GetEntryAssembly()?
+                    .GetCustomAttribute<TargetFrameworkAttribute>()?
+                    .FrameworkName;
+
                 // This can happen if, for example, a Java user tries to use Durable Functions while targeting V2 or V3 extension bundles
                 // because those bundles target .NET Core 2.2, which doesn't support the gRPC libraries used in the modern out-of-proc implementation.
                 throw new PlatformNotSupportedException(
-                    "This project type is not supported on this version of the Azure Functions runtime. Please upgrade to Azure Functions V3 or higher. " +
+                    $"{targetFramework}. This project type is not supported on this version of the Azure Functions runtime. Please upgrade to Azure Functions V3 or higher. " +
                     "If you are using a language that supports extension bundles, please use extension bundles V4 or higher. " +
                     "For more information on Azure Functions versions, see https://docs.microsoft.com/azure/azure-functions/functions-versions. " +
                     "For more information on extension bundles, see https://docs.microsoft.com/azure/azure-functions/functions-bindings-register#extension-bundles.");