regenerate code
diff --git a/src/csharp/Grpc.IntegrationTesting/ServicesGrpc.cs b/src/csharp/Grpc.IntegrationTesting/ServicesGrpc.cs
index beffa22..46b16cf 100644
--- a/src/csharp/Grpc.IntegrationTesting/ServicesGrpc.cs
+++ b/src/csharp/Grpc.IntegrationTesting/ServicesGrpc.cs
@@ -36,6 +36,7 @@
     }
 
     // client interface
+    [System.Obsolete("Client side interfaced will be removed in the next release. Use client class directly.")]
     public interface IBenchmarkServiceClient
     {
       global::Grpc.Testing.SimpleResponse UnaryCall(global::Grpc.Testing.SimpleRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken));
@@ -70,40 +71,50 @@
     }
 
     // client stub
-    public class BenchmarkServiceClient : ClientBase, IBenchmarkServiceClient
+    public class BenchmarkServiceClient : ClientBase<BenchmarkServiceClient>, IBenchmarkServiceClient
     {
       public BenchmarkServiceClient(Channel channel) : base(channel)
       {
       }
-      public global::Grpc.Testing.SimpleResponse UnaryCall(global::Grpc.Testing.SimpleRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      public BenchmarkServiceClient(CallInvoker callInvoker) : base(callInvoker)
       {
-        var call = CreateCall(__Method_UnaryCall, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.BlockingUnaryCall(call, request);
       }
-      public global::Grpc.Testing.SimpleResponse UnaryCall(global::Grpc.Testing.SimpleRequest request, CallOptions options)
+      ///<summary>Protected parameterless constructor to allow creation of test doubles.</summary>
+      protected BenchmarkServiceClient() : base()
       {
-        var call = CreateCall(__Method_UnaryCall, options);
-        return Calls.BlockingUnaryCall(call, request);
       }
-      public AsyncUnaryCall<global::Grpc.Testing.SimpleResponse> UnaryCallAsync(global::Grpc.Testing.SimpleRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      ///<summary>Protected constructor to allow creation of configured clients.</summary>
+      protected BenchmarkServiceClient(ClientBaseConfiguration configuration) : base(configuration)
       {
-        var call = CreateCall(__Method_UnaryCall, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.AsyncUnaryCall(call, request);
       }
-      public AsyncUnaryCall<global::Grpc.Testing.SimpleResponse> UnaryCallAsync(global::Grpc.Testing.SimpleRequest request, CallOptions options)
+
+      public virtual global::Grpc.Testing.SimpleResponse UnaryCall(global::Grpc.Testing.SimpleRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
-        var call = CreateCall(__Method_UnaryCall, options);
-        return Calls.AsyncUnaryCall(call, request);
+        return UnaryCall(request, new CallOptions(headers, deadline, cancellationToken));
       }
-      public AsyncDuplexStreamingCall<global::Grpc.Testing.SimpleRequest, global::Grpc.Testing.SimpleResponse> StreamingCall(Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      public virtual global::Grpc.Testing.SimpleResponse UnaryCall(global::Grpc.Testing.SimpleRequest request, CallOptions options)
       {
-        var call = CreateCall(__Method_StreamingCall, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.AsyncDuplexStreamingCall(call);
+        return CallInvoker.BlockingUnaryCall(__Method_UnaryCall, null, options, request);
       }
-      public AsyncDuplexStreamingCall<global::Grpc.Testing.SimpleRequest, global::Grpc.Testing.SimpleResponse> StreamingCall(CallOptions options)
+      public virtual AsyncUnaryCall<global::Grpc.Testing.SimpleResponse> UnaryCallAsync(global::Grpc.Testing.SimpleRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
-        var call = CreateCall(__Method_StreamingCall, options);
-        return Calls.AsyncDuplexStreamingCall(call);
+        return UnaryCallAsync(request, new CallOptions(headers, deadline, cancellationToken));
+      }
+      public virtual AsyncUnaryCall<global::Grpc.Testing.SimpleResponse> UnaryCallAsync(global::Grpc.Testing.SimpleRequest request, CallOptions options)
+      {
+        return CallInvoker.AsyncUnaryCall(__Method_UnaryCall, null, options, request);
+      }
+      public virtual AsyncDuplexStreamingCall<global::Grpc.Testing.SimpleRequest, global::Grpc.Testing.SimpleResponse> StreamingCall(Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      {
+        return StreamingCall(new CallOptions(headers, deadline, cancellationToken));
+      }
+      public virtual AsyncDuplexStreamingCall<global::Grpc.Testing.SimpleRequest, global::Grpc.Testing.SimpleResponse> StreamingCall(CallOptions options)
+      {
+        return CallInvoker.AsyncDuplexStreamingCall(__Method_StreamingCall, null, options);
+      }
+      protected override BenchmarkServiceClient NewInstance(ClientBaseConfiguration configuration)
+      {
+        return new BenchmarkServiceClient(configuration);
       }
     }
 
@@ -177,6 +188,7 @@
     }
 
     // client interface
+    [System.Obsolete("Client side interfaced will be removed in the next release. Use client class directly.")]
     public interface IWorkerServiceClient
     {
       AsyncDuplexStreamingCall<global::Grpc.Testing.ServerArgs, global::Grpc.Testing.ServerStatus> RunServer(Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken));
@@ -229,70 +241,74 @@
     }
 
     // client stub
-    public class WorkerServiceClient : ClientBase, IWorkerServiceClient
+    public class WorkerServiceClient : ClientBase<WorkerServiceClient>, IWorkerServiceClient
     {
       public WorkerServiceClient(Channel channel) : base(channel)
       {
       }
-      public AsyncDuplexStreamingCall<global::Grpc.Testing.ServerArgs, global::Grpc.Testing.ServerStatus> RunServer(Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      public WorkerServiceClient(CallInvoker callInvoker) : base(callInvoker)
       {
-        var call = CreateCall(__Method_RunServer, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.AsyncDuplexStreamingCall(call);
       }
-      public AsyncDuplexStreamingCall<global::Grpc.Testing.ServerArgs, global::Grpc.Testing.ServerStatus> RunServer(CallOptions options)
+      ///<summary>Protected parameterless constructor to allow creation of test doubles.</summary>
+      protected WorkerServiceClient() : base()
       {
-        var call = CreateCall(__Method_RunServer, options);
-        return Calls.AsyncDuplexStreamingCall(call);
       }
-      public AsyncDuplexStreamingCall<global::Grpc.Testing.ClientArgs, global::Grpc.Testing.ClientStatus> RunClient(Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      ///<summary>Protected constructor to allow creation of configured clients.</summary>
+      protected WorkerServiceClient(ClientBaseConfiguration configuration) : base(configuration)
       {
-        var call = CreateCall(__Method_RunClient, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.AsyncDuplexStreamingCall(call);
       }
-      public AsyncDuplexStreamingCall<global::Grpc.Testing.ClientArgs, global::Grpc.Testing.ClientStatus> RunClient(CallOptions options)
+
+      public virtual AsyncDuplexStreamingCall<global::Grpc.Testing.ServerArgs, global::Grpc.Testing.ServerStatus> RunServer(Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
-        var call = CreateCall(__Method_RunClient, options);
-        return Calls.AsyncDuplexStreamingCall(call);
+        return RunServer(new CallOptions(headers, deadline, cancellationToken));
       }
-      public global::Grpc.Testing.CoreResponse CoreCount(global::Grpc.Testing.CoreRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      public virtual AsyncDuplexStreamingCall<global::Grpc.Testing.ServerArgs, global::Grpc.Testing.ServerStatus> RunServer(CallOptions options)
       {
-        var call = CreateCall(__Method_CoreCount, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.BlockingUnaryCall(call, request);
+        return CallInvoker.AsyncDuplexStreamingCall(__Method_RunServer, null, options);
       }
-      public global::Grpc.Testing.CoreResponse CoreCount(global::Grpc.Testing.CoreRequest request, CallOptions options)
+      public virtual AsyncDuplexStreamingCall<global::Grpc.Testing.ClientArgs, global::Grpc.Testing.ClientStatus> RunClient(Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
-        var call = CreateCall(__Method_CoreCount, options);
-        return Calls.BlockingUnaryCall(call, request);
+        return RunClient(new CallOptions(headers, deadline, cancellationToken));
       }
-      public AsyncUnaryCall<global::Grpc.Testing.CoreResponse> CoreCountAsync(global::Grpc.Testing.CoreRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      public virtual AsyncDuplexStreamingCall<global::Grpc.Testing.ClientArgs, global::Grpc.Testing.ClientStatus> RunClient(CallOptions options)
       {
-        var call = CreateCall(__Method_CoreCount, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.AsyncUnaryCall(call, request);
+        return CallInvoker.AsyncDuplexStreamingCall(__Method_RunClient, null, options);
       }
-      public AsyncUnaryCall<global::Grpc.Testing.CoreResponse> CoreCountAsync(global::Grpc.Testing.CoreRequest request, CallOptions options)
+      public virtual global::Grpc.Testing.CoreResponse CoreCount(global::Grpc.Testing.CoreRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
-        var call = CreateCall(__Method_CoreCount, options);
-        return Calls.AsyncUnaryCall(call, request);
+        return CoreCount(request, new CallOptions(headers, deadline, cancellationToken));
       }
-      public global::Grpc.Testing.Void QuitWorker(global::Grpc.Testing.Void request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      public virtual global::Grpc.Testing.CoreResponse CoreCount(global::Grpc.Testing.CoreRequest request, CallOptions options)
       {
-        var call = CreateCall(__Method_QuitWorker, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.BlockingUnaryCall(call, request);
+        return CallInvoker.BlockingUnaryCall(__Method_CoreCount, null, options, request);
       }
-      public global::Grpc.Testing.Void QuitWorker(global::Grpc.Testing.Void request, CallOptions options)
+      public virtual AsyncUnaryCall<global::Grpc.Testing.CoreResponse> CoreCountAsync(global::Grpc.Testing.CoreRequest request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
-        var call = CreateCall(__Method_QuitWorker, options);
-        return Calls.BlockingUnaryCall(call, request);
+        return CoreCountAsync(request, new CallOptions(headers, deadline, cancellationToken));
       }
-      public AsyncUnaryCall<global::Grpc.Testing.Void> QuitWorkerAsync(global::Grpc.Testing.Void request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      public virtual AsyncUnaryCall<global::Grpc.Testing.CoreResponse> CoreCountAsync(global::Grpc.Testing.CoreRequest request, CallOptions options)
       {
-        var call = CreateCall(__Method_QuitWorker, new CallOptions(headers, deadline, cancellationToken));
-        return Calls.AsyncUnaryCall(call, request);
+        return CallInvoker.AsyncUnaryCall(__Method_CoreCount, null, options, request);
       }
-      public AsyncUnaryCall<global::Grpc.Testing.Void> QuitWorkerAsync(global::Grpc.Testing.Void request, CallOptions options)
+      public virtual global::Grpc.Testing.Void QuitWorker(global::Grpc.Testing.Void request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
-        var call = CreateCall(__Method_QuitWorker, options);
-        return Calls.AsyncUnaryCall(call, request);
+        return QuitWorker(request, new CallOptions(headers, deadline, cancellationToken));
+      }
+      public virtual global::Grpc.Testing.Void QuitWorker(global::Grpc.Testing.Void request, CallOptions options)
+      {
+        return CallInvoker.BlockingUnaryCall(__Method_QuitWorker, null, options, request);
+      }
+      public virtual AsyncUnaryCall<global::Grpc.Testing.Void> QuitWorkerAsync(global::Grpc.Testing.Void request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
+      {
+        return QuitWorkerAsync(request, new CallOptions(headers, deadline, cancellationToken));
+      }
+      public virtual AsyncUnaryCall<global::Grpc.Testing.Void> QuitWorkerAsync(global::Grpc.Testing.Void request, CallOptions options)
+      {
+        return CallInvoker.AsyncUnaryCall(__Method_QuitWorker, null, options, request);
+      }
+      protected override WorkerServiceClient NewInstance(ClientBaseConfiguration configuration)
+      {
+        return new WorkerServiceClient(configuration);
       }
     }