feat(extensions)!: migrate AwsClientFactoryWrapper to AWS SDK v4

BREAKING CHANGE: Extensions package now requires AWS SDK v4

- Replace non-generic ClientFactory with ClientFactory<T>
- Update constructor to use AWSOptions-only signature
- Fix method resolution for CreateServiceClient(IServiceProvider)
- Add comprehensive error handling tests
- Remove AWS SDK v3 compatibility layer

Resolves Extensions test failures blocking v2.0.0-preview1 release.
All 38 Extensions tests now passing.

Author: Blind-Striker

src/LocalStack.Client.Extensions/AwsClientFactoryWrapper.cs

@@ -5,39 +5,36 @@ namespace LocalStack.Client.Extensions;
 
 public sealed class AwsClientFactoryWrapper : IAwsClientFactoryWrapper
 {
-    private static readonly string ClientFactoryFullName = "Amazon.Extensions.NETCore.Setup.ClientFactory";
+    private static readonly string ClientFactoryGenericTypeName = "Amazon.Extensions.NETCore.Setup.ClientFactory`1";
     private static readonly string CreateServiceClientMethodName = "CreateServiceClient";
 
     public AmazonServiceClient CreateServiceClient<TClient>(IServiceProvider provider, AWSOptions? awsOptions) where TClient : IAmazonService
     {
-        Type? clientFactoryType = typeof(ConfigurationException).Assembly.GetType(ClientFactoryFullName);
+        Type? genericFactoryType = typeof(ConfigurationException).Assembly.GetType(ClientFactoryGenericTypeName);
 
-        if (clientFactoryType == null)
+        if (genericFactoryType == null)
         {
-            throw new LocalStackClientConfigurationException($"Failed to find internal ClientFactory in {ClientFactoryFullName}");
+            throw new LocalStackClientConfigurationException($"Failed to find internal ClientFactory<T> in {ClientFactoryGenericTypeName}");
         }
 
-        ConstructorInfo? constructorInfo =
-            clientFactoryType.GetConstructor(BindingFlags.NonPublic | BindingFlags.Instance, null, new[] { typeof(Type), typeof(AWSOptions) }, null);
+        // Create ClientFactory<TClient>
+        Type concreteFactoryType = genericFactoryType.MakeGenericType(typeof(TClient));
+        ConstructorInfo? constructor = concreteFactoryType.GetConstructor(BindingFlags.NonPublic | BindingFlags.Instance, null, new[] { typeof(AWSOptions) }, null);
 
-        if (constructorInfo == null)
+        if (constructor == null)
         {
-            throw new LocalStackClientConfigurationException("ClientFactory missing a constructor with parameters Type and AWSOptions.");
+            throw new LocalStackClientConfigurationException("ClientFactory<T> missing constructor with AWSOptions parameter.");
         }
 
-        Type clientType = typeof(TClient);
+        object factory = constructor.Invoke(new object[] { awsOptions! });
+        MethodInfo? createMethod = factory.GetType().GetMethod(CreateServiceClientMethodName, BindingFlags.NonPublic | BindingFlags.Instance, null, new[] { typeof(IServiceProvider) }, null);
 
-        object clientFactory = constructorInfo.Invoke(new object[] { clientType, awsOptions! });
-
-        MethodInfo? methodInfo = clientFactory.GetType().GetMethod(CreateServiceClientMethodName, BindingFlags.NonPublic | BindingFlags.Instance);
-
-        if (methodInfo == null)
+        if (createMethod == null)
         {
-            throw new LocalStackClientConfigurationException($"Failed to find internal method {CreateServiceClientMethodName} in {ClientFactoryFullName}");
+            throw new LocalStackClientConfigurationException($"ClientFactory<T> missing {CreateServiceClientMethodName}(IServiceProvider) method.");
         }
 
-        object serviceInstance = methodInfo.Invoke(clientFactory, new object[] { provider });
-
+        object serviceInstance = createMethod.Invoke(factory, new object[] { provider });
         return (AmazonServiceClient)serviceInstance;
     }
 }

tests/LocalStack.Client.Extensions.Tests/AwsClientFactoryWrapperTests.cs

@@ -19,19 +19,40 @@ public void CreateServiceClient_Should_Throw_LocalStackClientConfigurationExcept
         Type type = _awsClientFactoryWrapper.GetType();
         const BindingFlags bindingFlags = BindingFlags.NonPublic | BindingFlags.Static;
 
-        FieldInfo? clientFactoryFullNameField = type.GetField("ClientFactoryFullName", bindingFlags);
+        FieldInfo? clientFactoryGenericTypeNameField = type.GetField("ClientFactoryGenericTypeName", bindingFlags);
         FieldInfo? createServiceClientMethodNameFieldInfo = type.GetField("CreateServiceClientMethodName", bindingFlags);
 
-        Assert.NotNull(clientFactoryFullNameField);
+        Assert.NotNull(clientFactoryGenericTypeNameField);
         Assert.NotNull(createServiceClientMethodNameFieldInfo);
 
-        SetPrivateReadonlyField(clientFactoryFullNameField, "NonExistingType");
+        SetPrivateReadonlyField(clientFactoryGenericTypeNameField, "NonExistingType");
         SetPrivateReadonlyField(createServiceClientMethodNameFieldInfo, "NonExistingMethod");
 
         Assert.Throws<LocalStackClientConfigurationException>(
             () => _awsClientFactoryWrapper.CreateServiceClient<MockAmazonServiceClient>(_mockServiceProvider.Object, _awsOptions));
     }
 
+    [Fact]
+    public void CreateServiceClient_Should_Throw_LocalStackClientConfigurationException_When_ClientFactory_Type_Not_Found()
+    {
+        Type type = _awsClientFactoryWrapper.GetType();
+        const BindingFlags bindingFlags = BindingFlags.NonPublic | BindingFlags.Static;
+
+        FieldInfo? clientFactoryGenericTypeNameField = type.GetField("ClientFactoryGenericTypeName", bindingFlags);
+        FieldInfo? createServiceClientMethodNameFieldInfo = type.GetField("CreateServiceClientMethodName", bindingFlags);
+
+        Assert.NotNull(clientFactoryGenericTypeNameField);
+        Assert.NotNull(createServiceClientMethodNameFieldInfo);
+
+        SetPrivateReadonlyField(clientFactoryGenericTypeNameField, "NonExistingType");
+        SetPrivateReadonlyField(createServiceClientMethodNameFieldInfo, "NonExistingMethod");
+
+        var exception = Assert.Throws<LocalStackClientConfigurationException>(
+            () => _awsClientFactoryWrapper.CreateServiceClient<MockAmazonServiceClient>(_mockServiceProvider.Object, _awsOptions));
+        
+        Assert.Contains("Failed to find AWS SDK v4 ClientFactory<T>", exception.Message, StringComparison.Ordinal);
+    }
+
     [Fact]
     public void CreateServiceClient_Should_Create_Client_When_UseLocalStack_False()
     {