merge with upstream and resolve conflicts

6 files changed, 622 insertions, 128 deletions

diff --git a/include/grpc++/impl/call.h b/include/grpc++/impl/call.h
index aae199db1b..64fa5d6efb 100644
--- a/include/grpc++/impl/call.h
+++ b/include/grpc++/impl/call.h
@@ -34,14 +34,19 @@
 #ifndef GRPCXX_IMPL_CALL_H
 #define GRPCXX_IMPL_CALL_H
 
-#include <grpc/grpc.h>
+#include <grpc/support/alloc.h>
+#include <grpc++/client_context.h>
 #include <grpc++/completion_queue.h>
 #include <grpc++/config.h>
 #include <grpc++/status.h>
+#include <grpc++/impl/serialization_traits.h>
 
+#include <functional>
 #include <memory>
 #include <map>
 
+#include <string.h>
+
 struct grpc_call;
 struct grpc_op;
 
@@ -50,84 +55,383 @@ namespace grpc {
 class ByteBuffer;
 class Call;
 
-class CallOpBuffer : public CompletionQueueTag {
+void FillMetadataMap(grpc_metadata_array* arr,
+                     std::multimap<grpc::string, grpc::string>* metadata);
+grpc_metadata* FillMetadataArray(
+    const std::multimap<grpc::string, grpc::string>& metadata);
+
+/// Default argument for CallOpSet. I is unused by the class, but can be
+/// used for generating multiple names for the same thing.
+template <int I>
+class CallNoOp {
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {}
+  void FinishOp(bool* status, int max_message_size) {}
+};
+
+class CallOpSendInitialMetadata {
  public:
-  CallOpBuffer();
-  ~CallOpBuffer();
-
-  void Reset(void* next_return_tag);
-
-  // Does not take ownership.
-  void AddSendInitialMetadata(
-      std::multimap<grpc::string, grpc::string>* metadata);
-  void AddSendInitialMetadata(ClientContext* ctx);
-  void AddRecvInitialMetadata(ClientContext* ctx);
-  void AddSendMessage(const grpc::protobuf::Message& message);
-  void AddSendMessage(const ByteBuffer& message);
-  void AddRecvMessage(grpc::protobuf::Message* message);
-  void AddRecvMessage(ByteBuffer* message);
-  void AddClientSendClose();
-  void AddClientRecvStatus(ClientContext* ctx, Status* status);
-  void AddServerSendStatus(std::multimap<grpc::string, grpc::string>* metadata,
-                           const Status& status);
-  void AddServerRecvClose(bool* cancelled);
-
-  // INTERNAL API:
-
-  // Convert to an array of grpc_op elements
-  void FillOps(grpc_op* ops, size_t* nops);
-
-  // Called by completion queue just prior to returning from Next() or Pluck()
-  bool FinalizeResult(void** tag, bool* status) GRPC_OVERRIDE;
+  CallOpSendInitialMetadata() : send_(false) {}
 
-  void set_max_message_size(int max_message_size) {
-    max_message_size_ = max_message_size;
+  void SendInitialMetadata(
+      const std::multimap<grpc::string, grpc::string>& metadata) {
+    send_ = true;
+    initial_metadata_count_ = metadata.size();
+    initial_metadata_ = FillMetadataArray(metadata);
   }
 
-  bool got_message;
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!send_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_SEND_INITIAL_METADATA;
+    op->flags = 0;
+    op->data.send_initial_metadata.count = initial_metadata_count_;
+    op->data.send_initial_metadata.metadata = initial_metadata_;
+  }
+  void FinishOp(bool* status, int max_message_size) {
+    if (!send_) return;
+    gpr_free(initial_metadata_);
+    send_ = false;
+  }
 
- private:
-  void* return_tag_;
-  // Send initial metadata
-  bool send_initial_metadata_;
+  bool send_;
   size_t initial_metadata_count_;
   grpc_metadata* initial_metadata_;
-  // Recv initial metadta
-  std::multimap<grpc::string, grpc::string>* recv_initial_metadata_;
-  grpc_metadata_array recv_initial_metadata_arr_;
-  // Send message
-  const grpc::protobuf::Message* send_message_;
-  const ByteBuffer* send_message_buffer_;
+};
+
+class CallOpSendMessage {
+ public:
+  CallOpSendMessage() : send_buf_(nullptr), own_buf_(false) {}
+
+  template <class M>
+  Status SendMessage(const M& message) GRPC_MUST_USE_RESULT;
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (send_buf_ == nullptr) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_SEND_MESSAGE;
+    op->flags = 0;
+    op->data.send_message = send_buf_;
+  }
+  void FinishOp(bool* status, int max_message_size) {
+    if (own_buf_) grpc_byte_buffer_destroy(send_buf_);
+    send_buf_ = nullptr;
+  }
+
+ private:
   grpc_byte_buffer* send_buf_;
-  // Recv message
-  grpc::protobuf::Message* recv_message_;
-  ByteBuffer* recv_message_buffer_;
+  bool own_buf_;
+};
+
+template <class M>
+Status CallOpSendMessage::SendMessage(const M& message) {
+  return SerializationTraits<M>::Serialize(message, &send_buf_, &own_buf_);
+}
+
+template <class R>
+class CallOpRecvMessage {
+ public:
+  CallOpRecvMessage() : got_message(false), message_(nullptr) {}
+
+  void RecvMessage(R* message) { message_ = message; }
+
+  bool got_message;
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (message_ == nullptr) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_RECV_MESSAGE;
+    op->flags = 0;
+    op->data.recv_message = &recv_buf_;
+  }
+
+  void FinishOp(bool* status, int max_message_size) {
+    if (message_ == nullptr) return;
+    if (recv_buf_) {
+      if (*status) {
+        got_message = true;
+        *status = SerializationTraits<R>::Deserialize(recv_buf_, message_,
+                                                      max_message_size)
+                      .ok();
+      } else {
+        got_message = false;
+        grpc_byte_buffer_destroy(recv_buf_);
+      }
+    } else {
+      got_message = false;
+      *status = false;
+    }
+    message_ = nullptr;
+  }
+
+ private:
+  R* message_;
   grpc_byte_buffer* recv_buf_;
-  int max_message_size_;
-  // Client send close
-  bool client_send_close_;
-  // Client recv status
+};
+
+class CallOpGenericRecvMessage {
+ public:
+  CallOpGenericRecvMessage() : got_message(false) {}
+
+  template <class R>
+  void RecvMessage(R* message) {
+    deserialize_ = [message](grpc_byte_buffer* buf,
+                             int max_message_size) -> Status {
+      return SerializationTraits<R>::Deserialize(buf, message,
+                                                 max_message_size);
+    };
+  }
+
+  bool got_message;
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!deserialize_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_RECV_MESSAGE;
+    op->flags = 0;
+    op->data.recv_message = &recv_buf_;
+  }
+
+  void FinishOp(bool* status, int max_message_size) {
+    if (!deserialize_) return;
+    if (recv_buf_) {
+      if (*status) {
+        got_message = true;
+        *status = deserialize_(recv_buf_, max_message_size).ok();
+      } else {
+        got_message = false;
+        grpc_byte_buffer_destroy(recv_buf_);
+      }
+    } else {
+      got_message = false;
+      *status = false;
+    }
+    deserialize_ = DeserializeFunc();
+  }
+
+ private:
+  typedef std::function<Status(grpc_byte_buffer*, int)> DeserializeFunc;
+  DeserializeFunc deserialize_;
+  grpc_byte_buffer* recv_buf_;
+};
+
+class CallOpClientSendClose {
+ public:
+  CallOpClientSendClose() : send_(false) {}
+
+  void ClientSendClose() { send_ = true; }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!send_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
+    op->flags = 0;
+  }
+  void FinishOp(bool* status, int max_message_size) { send_ = false; }
+
+ private:
+  bool send_;
+};
+
+class CallOpServerSendStatus {
+ public:
+  CallOpServerSendStatus() : send_status_available_(false) {}
+
+  void ServerSendStatus(
+      const std::multimap<grpc::string, grpc::string>& trailing_metadata,
+      const Status& status) {
+    trailing_metadata_count_ = trailing_metadata.size();
+    trailing_metadata_ = FillMetadataArray(trailing_metadata);
+    send_status_available_ = true;
+    send_status_code_ = static_cast<grpc_status_code>(status.error_code());
+    send_status_details_ = status.error_message();
+  }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!send_status_available_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
+    op->data.send_status_from_server.trailing_metadata_count =
+        trailing_metadata_count_;
+    op->data.send_status_from_server.trailing_metadata = trailing_metadata_;
+    op->data.send_status_from_server.status = send_status_code_;
+    op->data.send_status_from_server.status_details =
+        send_status_details_.empty() ? nullptr : send_status_details_.c_str();
+    op->flags = 0;
+  }
+
+  void FinishOp(bool* status, int max_message_size) {
+    if (!send_status_available_) return;
+    gpr_free(trailing_metadata_);
+    send_status_available_ = false;
+  }
+
+ private:
+  bool send_status_available_;
+  grpc_status_code send_status_code_;
+  grpc::string send_status_details_;
+  size_t trailing_metadata_count_;
+  grpc_metadata* trailing_metadata_;
+};
+
+class CallOpRecvInitialMetadata {
+ public:
+  CallOpRecvInitialMetadata() : recv_initial_metadata_(nullptr) {}
+
+  void RecvInitialMetadata(ClientContext* context) {
+    context->initial_metadata_received_ = true;
+    recv_initial_metadata_ = &context->recv_initial_metadata_;
+  }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!recv_initial_metadata_) return;
+    memset(&recv_initial_metadata_arr_, 0, sizeof(recv_initial_metadata_arr_));
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_RECV_INITIAL_METADATA;
+    op->data.recv_initial_metadata = &recv_initial_metadata_arr_;
+    op->flags = 0;
+  }
+  void FinishOp(bool* status, int max_message_size) {
+    if (recv_initial_metadata_ == nullptr) return;
+    FillMetadataMap(&recv_initial_metadata_arr_, recv_initial_metadata_);
+    recv_initial_metadata_ = nullptr;
+  }
+
+ private:
+  std::multimap<grpc::string, grpc::string>* recv_initial_metadata_;
+  grpc_metadata_array recv_initial_metadata_arr_;
+};
+
+class CallOpClientRecvStatus {
+ public:
+  CallOpClientRecvStatus() : recv_status_(nullptr) {}
+
+  void ClientRecvStatus(ClientContext* context, Status* status) {
+    recv_trailing_metadata_ = &context->trailing_metadata_;
+    recv_status_ = status;
+  }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (recv_status_ == nullptr) return;
+    memset(&recv_trailing_metadata_arr_, 0,
+           sizeof(recv_trailing_metadata_arr_));
+    status_details_ = nullptr;
+    status_details_capacity_ = 0;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
+    op->data.recv_status_on_client.trailing_metadata =
+        &recv_trailing_metadata_arr_;
+    op->data.recv_status_on_client.status = &status_code_;
+    op->data.recv_status_on_client.status_details = &status_details_;
+    op->data.recv_status_on_client.status_details_capacity =
+        &status_details_capacity_;
+    op->flags = 0;
+  }
+
+  void FinishOp(bool* status, int max_message_size) {
+    if (recv_status_ == nullptr) return;
+    FillMetadataMap(&recv_trailing_metadata_arr_, recv_trailing_metadata_);
+    *recv_status_ = Status(
+        static_cast<StatusCode>(status_code_),
+        status_details_ ? grpc::string(status_details_) : grpc::string());
+    gpr_free(status_details_);
+    recv_status_ = nullptr;
+  }
+
+ private:
   std::multimap<grpc::string, grpc::string>* recv_trailing_metadata_;
   Status* recv_status_;
   grpc_metadata_array recv_trailing_metadata_arr_;
   grpc_status_code status_code_;
   char* status_details_;
   size_t status_details_capacity_;
-  // Server send status
-  bool send_status_available_;
-  grpc_status_code send_status_code_;
-  grpc::string send_status_details_;
-  size_t trailing_metadata_count_;
-  grpc_metadata* trailing_metadata_;
-  int cancelled_buf_;
-  bool* recv_closed_;
 };
 
-// SneakyCallOpBuffer does not post completions to the completion queue
-class SneakyCallOpBuffer GRPC_FINAL : public CallOpBuffer {
+/// An abstract collection of call ops, used to generate the
+/// grpc_call_op structure to pass down to the lower layers,
+/// and as it is-a CompletionQueueTag, also massages the final
+/// completion into the correct form for consumption in the C++
+/// API.
+class CallOpSetInterface : public CompletionQueueTag {
+ public:
+  CallOpSetInterface() : max_message_size_(0) {}
+  /// Fills in grpc_op, starting from ops[*nops] and moving
+  /// upwards.
+  virtual void FillOps(grpc_op* ops, size_t* nops) = 0;
+
+  void set_max_message_size(int max_message_size) {
+    max_message_size_ = max_message_size;
+  }
+
+ protected:
+  int max_message_size_;
+};
+
+/// Primary implementaiton of CallOpSetInterface.
+/// Since we cannot use variadic templates, we declare slots up to
+/// the maximum count of ops we'll need in a set. We leverage the
+/// empty base class optimization to slim this class (especially
+/// when there are many unused slots used). To avoid duplicate base classes,
+/// the template parmeter for CallNoOp is varied by argument position.
+template <class Op1 = CallNoOp<1>, class Op2 = CallNoOp<2>,
+          class Op3 = CallNoOp<3>, class Op4 = CallNoOp<4>,
+          class Op5 = CallNoOp<5>, class Op6 = CallNoOp<6>>
+class CallOpSet : public CallOpSetInterface,
+                  public Op1,
+                  public Op2,
+                  public Op3,
+                  public Op4,
+                  public Op5,
+                  public Op6 {
+ public:
+  CallOpSet() : return_tag_(this) {}
+  void FillOps(grpc_op* ops, size_t* nops) GRPC_OVERRIDE {
+    this->Op1::AddOp(ops, nops);
+    this->Op2::AddOp(ops, nops);
+    this->Op3::AddOp(ops, nops);
+    this->Op4::AddOp(ops, nops);
+    this->Op5::AddOp(ops, nops);
+    this->Op6::AddOp(ops, nops);
+  }
+
+  bool FinalizeResult(void** tag, bool* status) GRPC_OVERRIDE {
+    this->Op1::FinishOp(status, max_message_size_);
+    this->Op2::FinishOp(status, max_message_size_);
+    this->Op3::FinishOp(status, max_message_size_);
+    this->Op4::FinishOp(status, max_message_size_);
+    this->Op5::FinishOp(status, max_message_size_);
+    this->Op6::FinishOp(status, max_message_size_);
+    *tag = return_tag_;
+    return true;
+  }
+
+  void set_output_tag(void* return_tag) { return_tag_ = return_tag; }
+
+ private:
+  void* return_tag_;
+};
+
+/// A CallOpSet that does not post completions to the completion queue.
+///
+/// Allows hiding some completions that the C core must generate from
+/// C++ users.
+template <class Op1 = CallNoOp<1>, class Op2 = CallNoOp<2>,
+          class Op3 = CallNoOp<3>, class Op4 = CallNoOp<4>,
+          class Op5 = CallNoOp<5>, class Op6 = CallNoOp<6>>
+class SneakyCallOpSet GRPC_FINAL
+    : public CallOpSet<Op1, Op2, Op3, Op4, Op5, Op6> {
  public:
   bool FinalizeResult(void** tag, bool* status) GRPC_OVERRIDE {
-    return CallOpBuffer::FinalizeResult(tag, status) && false;
+    typedef CallOpSet<Op1, Op2, Op3, Op4, Op5, Op6> Base;
+    return Base::FinalizeResult(tag, status) && false;
   }
 };
 
@@ -135,7 +439,7 @@ class SneakyCallOpBuffer GRPC_FINAL : public CallOpBuffer {
 class CallHook {
  public:
   virtual ~CallHook() {}
-  virtual void PerformOpsOnCall(CallOpBuffer* ops, Call* call) = 0;
+  virtual void PerformOpsOnCall(CallOpSetInterface* ops, Call* call) = 0;
 };
 
 // Straightforward wrapping of the C call object
@@ -146,7 +450,7 @@ class Call GRPC_FINAL {
   Call(grpc_call* call, CallHook* call_hook_, CompletionQueue* cq,
        int max_message_size);
 
-  void PerformOps(CallOpBuffer* buffer);
+  void PerformOps(CallOpSetInterface* ops);
 
   grpc_call* call() { return call_; }
   CompletionQueue* cq() { return cq_; }
diff --git a/include/grpc++/impl/client_unary_call.h b/include/grpc++/impl/client_unary_call.h
index 2f234fd3ac..b77ce7d02c 100644
--- a/include/grpc++/impl/client_unary_call.h
+++ b/include/grpc++/impl/client_unary_call.h
@@ -37,6 +37,8 @@
 #include <grpc++/config.h>
 #include <grpc++/status.h>
 
+#include <grpc++/impl/call.h>
+
 namespace grpc {
 
 class ChannelInterface;
@@ -45,10 +47,28 @@ class CompletionQueue;
 class RpcMethod;
 
 // Wrapper that performs a blocking unary call
+template <class InputMessage, class OutputMessage>
 Status BlockingUnaryCall(ChannelInterface* channel, const RpcMethod& method,
-                         ClientContext* context,
-                         const grpc::protobuf::Message& request,
-                         grpc::protobuf::Message* result);
+                         ClientContext* context, const InputMessage& request,
+                         OutputMessage* result) {
+  CompletionQueue cq;
+  Call call(channel->CreateCall(method, context, &cq));
+  CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage,
+            CallOpRecvInitialMetadata, CallOpRecvMessage<OutputMessage>,
+            CallOpClientSendClose, CallOpClientRecvStatus> ops;
+  Status status = ops.SendMessage(request);
+  if (!status.ok()) {
+    return status;
+  }
+  ops.SendInitialMetadata(context->send_initial_metadata_);
+  ops.RecvInitialMetadata(context);
+  ops.RecvMessage(result);
+  ops.ClientSendClose();
+  ops.ClientRecvStatus(context, &status);
+  call.PerformOps(&ops);
+  GPR_ASSERT((cq.Pluck(&ops) && ops.got_message) || !status.ok());
+  return status;
+}
 
 }  // namespace grpc
 
diff --git a/include/grpc++/impl/proto_utils.h b/include/grpc++/impl/proto_utils.h
new file mode 100644
index 0000000000..ebefa3e1be
--- /dev/null
+++ b/include/grpc++/impl/proto_utils.h
@@ -0,0 +1,76 @@
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_INTERNAL_CPP_PROTO_PROTO_UTILS_H
+#define GRPC_INTERNAL_CPP_PROTO_PROTO_UTILS_H
+
+#include <type_traits>
+
+#include <grpc/grpc.h>
+#include <grpc++/impl/serialization_traits.h>
+#include <grpc++/config_protobuf.h>
+#include <grpc++/status.h>
+
+namespace grpc {
+
+// Serialize the msg into a buffer created inside the function. The caller
+// should destroy the returned buffer when done with it. If serialization fails,
+// false is returned and buffer is left unchanged.
+Status SerializeProto(const grpc::protobuf::Message& msg,
+                      grpc_byte_buffer** buffer);
+
+// The caller keeps ownership of buffer and msg.
+Status DeserializeProto(grpc_byte_buffer* buffer, grpc::protobuf::Message* msg,
+                        int max_message_size);
+
+template <class T>
+class SerializationTraits<T, typename std::enable_if<std::is_base_of<
+                                 grpc::protobuf::Message, T>::value>::type> {
+ public:
+  static Status Serialize(const grpc::protobuf::Message& msg,
+                          grpc_byte_buffer** buffer, bool* own_buffer) {
+    *own_buffer = true;
+    return SerializeProto(msg, buffer);
+  }
+  static Status Deserialize(grpc_byte_buffer* buffer,
+                            grpc::protobuf::Message* msg,
+                            int max_message_size) {
+    auto status = DeserializeProto(buffer, msg, max_message_size);
+    grpc_byte_buffer_destroy(buffer);
+    return status;
+  }
+};
+
+}  // namespace grpc
+
+#endif  // GRPC_INTERNAL_CPP_PROTO_PROTO_UTILS_H
diff --git a/include/grpc++/impl/rpc_service_method.h b/include/grpc++/impl/rpc_service_method.h
index 50204d2099..3cfbef7806 100644
--- a/include/grpc++/impl/rpc_service_method.h
+++ b/include/grpc++/impl/rpc_service_method.h
@@ -55,16 +55,19 @@ class MethodHandler {
  public:
   virtual ~MethodHandler() {}
   struct HandlerParameter {
-    HandlerParameter(Call* c, ServerContext* context,
-                     const grpc::protobuf::Message* req,
-                     grpc::protobuf::Message* resp)
-        : call(c), server_context(context), request(req), response(resp) {}
+    HandlerParameter(Call* c, ServerContext* context, grpc_byte_buffer* req,
+                     int max_size)
+        : call(c),
+          server_context(context),
+          request(req),
+          max_message_size(max_size) {}
     Call* call;
     ServerContext* server_context;
-    const grpc::protobuf::Message* request;
-    grpc::protobuf::Message* response;
+    // Handler required to grpc_byte_buffer_destroy this
+    grpc_byte_buffer* request;
+    int max_message_size;
   };
-  virtual Status RunHandler(const HandlerParameter& param) = 0;
+  virtual void RunHandler(const HandlerParameter& param) = 0;
 };
 
 // A wrapper class of an application provided rpc method handler.
@@ -77,11 +80,25 @@ class RpcMethodHandler : public MethodHandler {
       ServiceType* service)
       : func_(func), service_(service) {}
 
-  Status RunHandler(const HandlerParameter& param) GRPC_FINAL {
-    // Invoke application function, cast proto messages to their actual types.
-    return func_(service_, param.server_context,
-                 dynamic_cast<const RequestType*>(param.request),
-                 dynamic_cast<ResponseType*>(param.response));
+  void RunHandler(const HandlerParameter& param) GRPC_FINAL {
+    RequestType req;
+    Status status = SerializationTraits<RequestType>::Deserialize(
+        param.request, &req, param.max_message_size);
+    ResponseType rsp;
+    if (status.ok()) {
+      status = func_(service_, param.server_context, &req, &rsp);
+    }
+
+    GPR_ASSERT(!param.server_context->sent_initial_metadata_);
+    CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage,
+              CallOpServerSendStatus> ops;
+    ops.SendInitialMetadata(param.server_context->initial_metadata_);
+    if (status.ok()) {
+      status = ops.SendMessage(rsp);
+    }
+    ops.ServerSendStatus(param.server_context->trailing_metadata_, status);
+    param.call->PerformOps(&ops);
+    param.call->cq()->Pluck(&ops);
   }
 
  private:
@@ -102,10 +119,21 @@ class ClientStreamingHandler : public MethodHandler {
       ServiceType* service)
       : func_(func), service_(service) {}
 
-  Status RunHandler(const HandlerParameter& param) GRPC_FINAL {
+  void RunHandler(const HandlerParameter& param) GRPC_FINAL {
     ServerReader<RequestType> reader(param.call, param.server_context);
-    return func_(service_, param.server_context, &reader,
-                 dynamic_cast<ResponseType*>(param.response));
+    ResponseType rsp;
+    Status status = func_(service_, param.server_context, &reader, &rsp);
+
+    GPR_ASSERT(!param.server_context->sent_initial_metadata_);
+    CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage,
+              CallOpServerSendStatus> ops;
+    ops.SendInitialMetadata(param.server_context->initial_metadata_);
+    if (status.ok()) {
+      status = ops.SendMessage(rsp);
+    }
+    ops.ServerSendStatus(param.server_context->trailing_metadata_, status);
+    param.call->PerformOps(&ops);
+    param.call->cq()->Pluck(&ops);
   }
 
  private:
@@ -124,10 +152,23 @@ class ServerStreamingHandler : public MethodHandler {
       ServiceType* service)
       : func_(func), service_(service) {}
 
-  Status RunHandler(const HandlerParameter& param) GRPC_FINAL {
-    ServerWriter<ResponseType> writer(param.call, param.server_context);
-    return func_(service_, param.server_context,
-                 dynamic_cast<const RequestType*>(param.request), &writer);
+  void RunHandler(const HandlerParameter& param) GRPC_FINAL {
+    RequestType req;
+    Status status = SerializationTraits<RequestType>::Deserialize(
+        param.request, &req, param.max_message_size);
+
+    if (status.ok()) {
+      ServerWriter<ResponseType> writer(param.call, param.server_context);
+      status = func_(service_, param.server_context, &req, &writer);
+    }
+
+    CallOpSet<CallOpSendInitialMetadata, CallOpServerSendStatus> ops;
+    if (!param.server_context->sent_initial_metadata_) {
+      ops.SendInitialMetadata(param.server_context->initial_metadata_);
+    }
+    ops.ServerSendStatus(param.server_context->trailing_metadata_, status);
+    param.call->PerformOps(&ops);
+    param.call->cq()->Pluck(&ops);
   }
 
  private:
@@ -147,10 +188,18 @@ class BidiStreamingHandler : public MethodHandler {
       ServiceType* service)
       : func_(func), service_(service) {}
 
-  Status RunHandler(const HandlerParameter& param) GRPC_FINAL {
+  void RunHandler(const HandlerParameter& param) GRPC_FINAL {
     ServerReaderWriter<ResponseType, RequestType> stream(param.call,
                                                          param.server_context);
-    return func_(service_, param.server_context, &stream);
+    Status status = func_(service_, param.server_context, &stream);
+
+    CallOpSet<CallOpSendInitialMetadata, CallOpServerSendStatus> ops;
+    if (!param.server_context->sent_initial_metadata_) {
+      ops.SendInitialMetadata(param.server_context->initial_metadata_);
+    }
+    ops.ServerSendStatus(param.server_context->trailing_metadata_, status);
+    param.call->PerformOps(&ops);
+    param.call->cq()->Pluck(&ops);
   }
 
  private:
@@ -162,29 +211,15 @@ class BidiStreamingHandler : public MethodHandler {
 // Server side rpc method class
 class RpcServiceMethod : public RpcMethod {
  public:
-  // Takes ownership of the handler and two prototype objects.
+  // Takes ownership of the handler
   RpcServiceMethod(const char* name, RpcMethod::RpcType type,
-                   MethodHandler* handler,
-                   grpc::protobuf::Message* request_prototype,
-                   grpc::protobuf::Message* response_prototype)
-      : RpcMethod(name, type, nullptr),
-        handler_(handler),
-        request_prototype_(request_prototype),
-        response_prototype_(response_prototype) {}
+                   MethodHandler* handler)
+      : RpcMethod(name, type, nullptr), handler_(handler) {}
 
   MethodHandler* handler() { return handler_.get(); }
 
-  grpc::protobuf::Message* AllocateRequestProto() {
-    return request_prototype_->New();
-  }
-  grpc::protobuf::Message* AllocateResponseProto() {
-    return response_prototype_->New();
-  }
-
  private:
   std::unique_ptr<MethodHandler> handler_;
-  std::unique_ptr<grpc::protobuf::Message> request_prototype_;
-  std::unique_ptr<grpc::protobuf::Message> response_prototype_;
 };
 
 // This class contains all the method information for an rpc service. It is
diff --git a/include/grpc++/impl/serialization_traits.h b/include/grpc++/impl/serialization_traits.h
new file mode 100644
index 0000000000..1f5c674e4c
--- /dev/null
+++ b/include/grpc++/impl/serialization_traits.h
@@ -0,0 +1,68 @@
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPCXX_IMPL_SERIALIZATION_TRAITS_H
+#define GRPCXX_IMPL_SERIALIZATION_TRAITS_H
+
+namespace grpc {
+
+/// Defines how to serialize and deserialize some type.
+/// 
+/// Used for hooking different message serialization API's into GRPC.
+/// Each SerializationTraits implementation must provide the following
+/// functions:
+///   static Status Serialize(const Message& msg,
+///                           grpc_byte_buffer** buffer, 
+//                            bool* own_buffer);
+///   static Status Deserialize(grpc_byte_buffer* buffer,
+///                             Message* msg,
+///                             int max_message_size);
+///
+/// Serialize is required to convert message to a grpc_byte_buffer, and
+/// to store a pointer to that byte buffer at *buffer. *own_buffer should
+/// be set to true if the caller owns said byte buffer, or false if
+/// ownership is retained elsewhere.
+///
+/// Deserialize is required to convert buffer into the message stored at
+/// msg. max_message_size is passed in as a bound on the maximum number of
+/// message bytes Deserialize should accept.
+///
+/// Both functions return a Status, allowing them to explain what went 
+/// wrong if required.
+template <class Message,
+          class UnusedButHereForPartialTemplateSpecialization = void>
+class SerializationTraits;
+
+}  // namespace grpc
+
+#endif  // GRPCXX_IMPL_SERIALIZATION_TRAITS_H
diff --git a/include/grpc++/impl/service_type.h b/include/grpc++/impl/service_type.h
index 25e437edad..c33a278f5b 100644
--- a/include/grpc++/impl/service_type.h
+++ b/include/grpc++/impl/service_type.h
@@ -35,6 +35,8 @@
 #define GRPCXX_IMPL_SERVICE_TYPE_H
 
 #include <grpc++/config.h>
+#include <grpc++/impl/serialization_traits.h>
+#include <grpc++/server.h>
 #include <grpc++/status.h>
 
 namespace grpc {
@@ -65,20 +67,8 @@ class ServerAsyncStreamingInterface {
 
 class AsynchronousService {
  public:
-  // this is Server, but in disguise to avoid a link dependency
-  class DispatchImpl {
-   public:
-    virtual void RequestAsyncCall(void* registered_method,
-                                  ServerContext* context,
-                                  ::grpc::protobuf::Message* request,
-                                  ServerAsyncStreamingInterface* stream,
-                                  CompletionQueue* call_cq,
-                                  ServerCompletionQueue* notification_cq,
-                                  void* tag) = 0;
-  };
-
   AsynchronousService(const char** method_names, size_t method_count)
-      : dispatch_impl_(nullptr),
+      : server_(nullptr),
         method_names_(method_names),
         method_count_(method_count),
         request_args_(nullptr) {}
@@ -86,42 +76,43 @@ class AsynchronousService {
   ~AsynchronousService() { delete[] request_args_; }
 
  protected:
-  void RequestAsyncUnary(int index, ServerContext* context,
-                         grpc::protobuf::Message* request,
+  template <class Message>
+  void RequestAsyncUnary(int index, ServerContext* context, Message* request,
                          ServerAsyncStreamingInterface* stream,
                          CompletionQueue* call_cq,
                          ServerCompletionQueue* notification_cq, void* tag) {
-    dispatch_impl_->RequestAsyncCall(request_args_[index], context, request,
-                                     stream, call_cq, notification_cq, tag);
+    server_->RequestAsyncCall(request_args_[index], context, stream, call_cq,
+                              notification_cq, tag, request);
   }
   void RequestClientStreaming(int index, ServerContext* context,
                               ServerAsyncStreamingInterface* stream,
                               CompletionQueue* call_cq,
                               ServerCompletionQueue* notification_cq,
                               void* tag) {
-    dispatch_impl_->RequestAsyncCall(request_args_[index], context, nullptr,
-                                     stream, call_cq, notification_cq, tag);
+    server_->RequestAsyncCall(request_args_[index], context, stream, call_cq,
+                              notification_cq, tag);
   }
+  template <class Message>
   void RequestServerStreaming(int index, ServerContext* context,
-                              grpc::protobuf::Message* request,
+                              Message* request,
                               ServerAsyncStreamingInterface* stream,
                               CompletionQueue* call_cq,
                               ServerCompletionQueue* notification_cq,
                               void* tag) {
-    dispatch_impl_->RequestAsyncCall(request_args_[index], context, request,
-                                     stream, call_cq, notification_cq, tag);
+    server_->RequestAsyncCall(request_args_[index], context, stream, call_cq,
+                              notification_cq, tag, request);
   }
   void RequestBidiStreaming(int index, ServerContext* context,
                             ServerAsyncStreamingInterface* stream,
                             CompletionQueue* call_cq,
                             ServerCompletionQueue* notification_cq, void* tag) {
-    dispatch_impl_->RequestAsyncCall(request_args_[index], context, nullptr,
-                                     stream, call_cq, notification_cq, tag);
+    server_->RequestAsyncCall(request_args_[index], context, stream, call_cq,
+                              notification_cq, tag);
   }
 
  private:
   friend class Server;
-  DispatchImpl* dispatch_impl_;
+  Server* server_;
   const char** const method_names_;
   size_t method_count_;
   void** request_args_;