Address reviewer comments and remove binary files

13 files changed, 29 insertions, 1329 deletions

diff --git a/examples/BUILD b/examples/BUILD
index 0f18cfa9ba..22f2f0a4f1 100644
--- a/examples/BUILD
+++ b/examples/BUILD
@@ -51,3 +51,18 @@ cc_binary(
     defines = ["BAZEL_BUILD"],
     deps = [":helloworld", "//:grpc++"],
 )
+
+cc_binary(
+    name = "metadata_client",
+    srcs = ["cpp/metadata/greeter_client.cc"],
+    defines = ["BAZEL_BUILD"],
+    deps = [":helloworld", "//:grpc++"],
+)
+
+cc_binary(
+    name = "metadata_server",
+    srcs = ["cpp/metadata/greeter_server.cc"],
+    defines = ["BAZEL_BUILD"],
+    deps = [":helloworld", "//:grpc++"],
+)
+
diff --git a/examples/cpp/metadata/README.md b/examples/cpp/metadata/README.md
index 7b33074ba1..96ad3d19bd 100644
--- a/examples/cpp/metadata/README.md
+++ b/examples/cpp/metadata/README.md
@@ -57,13 +57,10 @@ If things go smoothly, you will see in the client terminal:
 
 And in the server terminal:
 
-"Header key: custom-bin , value: 
"
+"Header key: custom-bin , value: 01234567"
 "Header key: custom-header , value: Custom Value"
 "Header key: user-agent , value: grpc-c++/1.16.0-dev grpc-c/6.0.0-dev (linux; chttp2; gao)"
 
-Note that the value for custom-bin doesn't print nicely because it's a binary 
-value. You can indicate a binary value through appending "-bin" to the header key.
-
 We did not add the user-agent metadata as a custom header. This shows how 
 the gRPC framework adds some headers under the hood that may show up in the 
 metadata map.
diff --git a/examples/cpp/metadata/greeter_client b/examples/cpp/metadata/greeter_client
deleted file mode 100755
index 929a51c3a5..0000000000
--- a/examples/cpp/metadata/greeter_client
+++ /dev/null
diff --git a/examples/cpp/metadata/greeter_client.o b/examples/cpp/metadata/greeter_client.o
deleted file mode 100644
index 483cb0741c..0000000000
--- a/examples/cpp/metadata/greeter_client.o
+++ /dev/null
diff --git a/examples/cpp/metadata/greeter_server b/examples/cpp/metadata/greeter_server
deleted file mode 100755
index 6b03f51475..0000000000
--- a/examples/cpp/metadata/greeter_server
+++ /dev/null
diff --git a/examples/cpp/metadata/greeter_server.cc b/examples/cpp/metadata/greeter_server.cc
index db2fecbcaf..a9a4f33cb0 100644
--- a/examples/cpp/metadata/greeter_server.cc
+++ b/examples/cpp/metadata/greeter_server.cc
@@ -46,7 +46,19 @@ class GreeterServiceImpl final : public Greeter::Service {
     std::cout << "Client metadata: " << std::endl;
     const std::multimap<grpc::string_ref, grpc::string_ref> metadata = context->client_metadata();
     for (auto iter = metadata.begin(); iter != metadata.end(); ++iter) {
-      std::cout << "Header key: " << iter->first << " , value: " << iter->second << std::endl;
+      std::cout << "Header key: " << iter->first << ", value: ";
+      // Check for binary value
+      size_t isbin = iter->first.find("-bin");
+      if ((isbin != std::string::npos) && (isbin + 4 == iter->first.size())) {
+        std::cout <<  std::hex;
+        for (auto c : iter->second) {
+          std::cout << static_cast<unsigned int>(c);
+        }
+        std::cout <<  std::dec;
+      } else {
+        std::cout << iter->second;
+      }
+      std::cout << std::endl;
     }
 
     context->AddInitialMetadata("custom-server-metadata", "initial metadata value");
diff --git a/examples/cpp/metadata/greeter_server.o b/examples/cpp/metadata/greeter_server.o
deleted file mode 100644
index dc197b2d14..0000000000
--- a/examples/cpp/metadata/greeter_server.o
+++ /dev/null
diff --git a/examples/cpp/metadata/helloworld.grpc.pb.cc b/examples/cpp/metadata/helloworld.grpc.pb.cc
deleted file mode 100644
index 4255687148..0000000000
--- a/examples/cpp/metadata/helloworld.grpc.pb.cc
+++ /dev/null
@@ -1,70 +0,0 @@
-// Generated by the gRPC C++ plugin.
-// If you make any local change, they will be lost.
-// source: helloworld.proto
-
-#include "helloworld.pb.h"
-#include "helloworld.grpc.pb.h"
-
-#include <functional>
-#include <grpcpp/impl/codegen/async_stream.h>
-#include <grpcpp/impl/codegen/async_unary_call.h>
-#include <grpcpp/impl/codegen/channel_interface.h>
-#include <grpcpp/impl/codegen/client_unary_call.h>
-#include <grpcpp/impl/codegen/client_callback.h>
-#include <grpcpp/impl/codegen/method_handler_impl.h>
-#include <grpcpp/impl/codegen/rpc_service_method.h>
-#include <grpcpp/impl/codegen/service_type.h>
-#include <grpcpp/impl/codegen/sync_stream.h>
-namespace helloworld {
-
-static const char* Greeter_method_names[] = {
-  "/helloworld.Greeter/SayHello",
-};
-
-std::unique_ptr< Greeter::Stub> Greeter::NewStub(const std::shared_ptr< ::grpc::ChannelInterface>& channel, const ::grpc::StubOptions& options) {
-  (void)options;
-  std::unique_ptr< Greeter::Stub> stub(new Greeter::Stub(channel));
-  return stub;
-}
-
-Greeter::Stub::Stub(const std::shared_ptr< ::grpc::ChannelInterface>& channel)
-  : channel_(channel), rpcmethod_SayHello_(Greeter_method_names[0], ::grpc::internal::RpcMethod::NORMAL_RPC, channel)
-  {}
-
-::grpc::Status Greeter::Stub::SayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::helloworld::HelloReply* response) {
-  return ::grpc::internal::BlockingUnaryCall(channel_.get(), rpcmethod_SayHello_, context, request, response);
-}
-
-void Greeter::Stub::experimental_async::SayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response, std::function<void(::grpc::Status)> f) {
-  return ::grpc::internal::CallbackUnaryCall(stub_->channel_.get(), stub_->rpcmethod_SayHello_, context, request, response, std::move(f));
-}
-
-::grpc::ClientAsyncResponseReader< ::helloworld::HelloReply>* Greeter::Stub::AsyncSayHelloRaw(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) {
-  return ::grpc::internal::ClientAsyncResponseReaderFactory< ::helloworld::HelloReply>::Create(channel_.get(), cq, rpcmethod_SayHello_, context, request, true);
-}
-
-::grpc::ClientAsyncResponseReader< ::helloworld::HelloReply>* Greeter::Stub::PrepareAsyncSayHelloRaw(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) {
-  return ::grpc::internal::ClientAsyncResponseReaderFactory< ::helloworld::HelloReply>::Create(channel_.get(), cq, rpcmethod_SayHello_, context, request, false);
-}
-
-Greeter::Service::Service() {
-  AddMethod(new ::grpc::internal::RpcServiceMethod(
-      Greeter_method_names[0],
-      ::grpc::internal::RpcMethod::NORMAL_RPC,
-      new ::grpc::internal::RpcMethodHandler< Greeter::Service, ::helloworld::HelloRequest, ::helloworld::HelloReply>(
-          std::mem_fn(&Greeter::Service::SayHello), this)));
-}
-
-Greeter::Service::~Service() {
-}
-
-::grpc::Status Greeter::Service::SayHello(::grpc::ServerContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response) {
-  (void) context;
-  (void) request;
-  (void) response;
-  return ::grpc::Status(::grpc::StatusCode::UNIMPLEMENTED, "");
-}
-
-
-}  // namespace helloworld
-
diff --git a/examples/cpp/metadata/helloworld.grpc.pb.h b/examples/cpp/metadata/helloworld.grpc.pb.h
deleted file mode 100644
index 73cc75e0a6..0000000000
--- a/examples/cpp/metadata/helloworld.grpc.pb.h
+++ /dev/null
@@ -1,197 +0,0 @@
-// Generated by the gRPC C++ plugin.
-// If you make any local change, they will be lost.
-// source: helloworld.proto
-// Original file comments:
-// Copyright 2015 gRPC authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-#ifndef GRPC_helloworld_2eproto__INCLUDED
-#define GRPC_helloworld_2eproto__INCLUDED
-
-#include "helloworld.pb.h"
-
-#include <functional>
-#include <grpcpp/impl/codegen/async_generic_service.h>
-#include <grpcpp/impl/codegen/async_stream.h>
-#include <grpcpp/impl/codegen/async_unary_call.h>
-#include <grpcpp/impl/codegen/method_handler_impl.h>
-#include <grpcpp/impl/codegen/proto_utils.h>
-#include <grpcpp/impl/codegen/rpc_method.h>
-#include <grpcpp/impl/codegen/service_type.h>
-#include <grpcpp/impl/codegen/status.h>
-#include <grpcpp/impl/codegen/stub_options.h>
-#include <grpcpp/impl/codegen/sync_stream.h>
-
-namespace grpc {
-class CompletionQueue;
-class Channel;
-class ServerCompletionQueue;
-class ServerContext;
-}  // namespace grpc
-
-namespace helloworld {
-
-// The greeting service definition.
-class Greeter final {
- public:
-  static constexpr char const* service_full_name() {
-    return "helloworld.Greeter";
-  }
-  class StubInterface {
-   public:
-    virtual ~StubInterface() {}
-    // Sends a greeting
-    virtual ::grpc::Status SayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::helloworld::HelloReply* response) = 0;
-    std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::helloworld::HelloReply>> AsyncSayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) {
-      return std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::helloworld::HelloReply>>(AsyncSayHelloRaw(context, request, cq));
-    }
-    std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::helloworld::HelloReply>> PrepareAsyncSayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) {
-      return std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::helloworld::HelloReply>>(PrepareAsyncSayHelloRaw(context, request, cq));
-    }
-    class experimental_async_interface {
-     public:
-      virtual ~experimental_async_interface() {}
-      // Sends a greeting
-      virtual void SayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response, std::function<void(::grpc::Status)>) = 0;
-    };
-    virtual class experimental_async_interface* experimental_async() { return nullptr; }
-  private:
-    virtual ::grpc::ClientAsyncResponseReaderInterface< ::helloworld::HelloReply>* AsyncSayHelloRaw(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) = 0;
-    virtual ::grpc::ClientAsyncResponseReaderInterface< ::helloworld::HelloReply>* PrepareAsyncSayHelloRaw(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) = 0;
-  };
-  class Stub final : public StubInterface {
-   public:
-    Stub(const std::shared_ptr< ::grpc::ChannelInterface>& channel);
-    ::grpc::Status SayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::helloworld::HelloReply* response) override;
-    std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::helloworld::HelloReply>> AsyncSayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) {
-      return std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::helloworld::HelloReply>>(AsyncSayHelloRaw(context, request, cq));
-    }
-    std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::helloworld::HelloReply>> PrepareAsyncSayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) {
-      return std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::helloworld::HelloReply>>(PrepareAsyncSayHelloRaw(context, request, cq));
-    }
-    class experimental_async final :
-      public StubInterface::experimental_async_interface {
-     public:
-      void SayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response, std::function<void(::grpc::Status)>) override;
-     private:
-      friend class Stub;
-      explicit experimental_async(Stub* stub): stub_(stub) { }
-      Stub* stub() { return stub_; }
-      Stub* stub_;
-    };
-    class experimental_async_interface* experimental_async() override { return &async_stub_; }
-
-   private:
-    std::shared_ptr< ::grpc::ChannelInterface> channel_;
-    class experimental_async async_stub_{this};
-    ::grpc::ClientAsyncResponseReader< ::helloworld::HelloReply>* AsyncSayHelloRaw(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) override;
-    ::grpc::ClientAsyncResponseReader< ::helloworld::HelloReply>* PrepareAsyncSayHelloRaw(::grpc::ClientContext* context, const ::helloworld::HelloRequest& request, ::grpc::CompletionQueue* cq) override;
-    const ::grpc::internal::RpcMethod rpcmethod_SayHello_;
-  };
-  static std::unique_ptr<Stub> NewStub(const std::shared_ptr< ::grpc::ChannelInterface>& channel, const ::grpc::StubOptions& options = ::grpc::StubOptions());
-
-  class Service : public ::grpc::Service {
-   public:
-    Service();
-    virtual ~Service();
-    // Sends a greeting
-    virtual ::grpc::Status SayHello(::grpc::ServerContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response);
-  };
-  template <class BaseClass>
-  class WithAsyncMethod_SayHello : public BaseClass {
-   private:
-    void BaseClassMustBeDerivedFromService(const Service *service) {}
-   public:
-    WithAsyncMethod_SayHello() {
-      ::grpc::Service::MarkMethodAsync(0);
-    }
-    ~WithAsyncMethod_SayHello() override {
-      BaseClassMustBeDerivedFromService(this);
-    }
-    // disable synchronous version of this method
-    ::grpc::Status SayHello(::grpc::ServerContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response) override {
-      abort();
-      return ::grpc::Status(::grpc::StatusCode::UNIMPLEMENTED, "");
-    }
-    void RequestSayHello(::grpc::ServerContext* context, ::helloworld::HelloRequest* request, ::grpc::ServerAsyncResponseWriter< ::helloworld::HelloReply>* response, ::grpc::CompletionQueue* new_call_cq, ::grpc::ServerCompletionQueue* notification_cq, void *tag) {
-      ::grpc::Service::RequestAsyncUnary(0, context, request, response, new_call_cq, notification_cq, tag);
-    }
-  };
-  typedef WithAsyncMethod_SayHello<Service > AsyncService;
-  template <class BaseClass>
-  class WithGenericMethod_SayHello : public BaseClass {
-   private:
-    void BaseClassMustBeDerivedFromService(const Service *service) {}
-   public:
-    WithGenericMethod_SayHello() {
-      ::grpc::Service::MarkMethodGeneric(0);
-    }
-    ~WithGenericMethod_SayHello() override {
-      BaseClassMustBeDerivedFromService(this);
-    }
-    // disable synchronous version of this method
-    ::grpc::Status SayHello(::grpc::ServerContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response) override {
-      abort();
-      return ::grpc::Status(::grpc::StatusCode::UNIMPLEMENTED, "");
-    }
-  };
-  template <class BaseClass>
-  class WithRawMethod_SayHello : public BaseClass {
-   private:
-    void BaseClassMustBeDerivedFromService(const Service *service) {}
-   public:
-    WithRawMethod_SayHello() {
-      ::grpc::Service::MarkMethodRaw(0);
-    }
-    ~WithRawMethod_SayHello() override {
-      BaseClassMustBeDerivedFromService(this);
-    }
-    // disable synchronous version of this method
-    ::grpc::Status SayHello(::grpc::ServerContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response) override {
-      abort();
-      return ::grpc::Status(::grpc::StatusCode::UNIMPLEMENTED, "");
-    }
-    void RequestSayHello(::grpc::ServerContext* context, ::grpc::ByteBuffer* request, ::grpc::ServerAsyncResponseWriter< ::grpc::ByteBuffer>* response, ::grpc::CompletionQueue* new_call_cq, ::grpc::ServerCompletionQueue* notification_cq, void *tag) {
-      ::grpc::Service::RequestAsyncUnary(0, context, request, response, new_call_cq, notification_cq, tag);
-    }
-  };
-  template <class BaseClass>
-  class WithStreamedUnaryMethod_SayHello : public BaseClass {
-   private:
-    void BaseClassMustBeDerivedFromService(const Service *service) {}
-   public:
-    WithStreamedUnaryMethod_SayHello() {
-      ::grpc::Service::MarkMethodStreamed(0,
-        new ::grpc::internal::StreamedUnaryHandler< ::helloworld::HelloRequest, ::helloworld::HelloReply>(std::bind(&WithStreamedUnaryMethod_SayHello<BaseClass>::StreamedSayHello, this, std::placeholders::_1, std::placeholders::_2)));
-    }
-    ~WithStreamedUnaryMethod_SayHello() override {
-      BaseClassMustBeDerivedFromService(this);
-    }
-    // disable regular version of this method
-    ::grpc::Status SayHello(::grpc::ServerContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response) override {
-      abort();
-      return ::grpc::Status(::grpc::StatusCode::UNIMPLEMENTED, "");
-    }
-    // replace default version of method with streamed unary
-    virtual ::grpc::Status StreamedSayHello(::grpc::ServerContext* context, ::grpc::ServerUnaryStreamer< ::helloworld::HelloRequest,::helloworld::HelloReply>* server_unary_streamer) = 0;
-  };
-  typedef WithStreamedUnaryMethod_SayHello<Service > StreamedUnaryService;
-  typedef Service SplitStreamedService;
-  typedef WithStreamedUnaryMethod_SayHello<Service > StreamedService;
-};
-
-}  // namespace helloworld
-
-
-#endif  // GRPC_helloworld_2eproto__INCLUDED
diff --git a/examples/cpp/metadata/helloworld.grpc.pb.o b/examples/cpp/metadata/helloworld.grpc.pb.o
deleted file mode 100644
index 234283660c..0000000000
--- a/examples/cpp/metadata/helloworld.grpc.pb.o
+++ /dev/null
diff --git a/examples/cpp/metadata/helloworld.pb.cc b/examples/cpp/metadata/helloworld.pb.cc
deleted file mode 100644
index cfbc8d3194..0000000000
--- a/examples/cpp/metadata/helloworld.pb.cc
+++ /dev/null
@@ -1,638 +0,0 @@
-// Generated by the protocol buffer compiler.  DO NOT EDIT!
-// source: helloworld.proto
-
-#include "helloworld.pb.h"
-
-#include <algorithm>
-
-#include <google/protobuf/stubs/common.h>
-#include <google/protobuf/stubs/port.h>
-#include <google/protobuf/io/coded_stream.h>
-#include <google/protobuf/wire_format_lite_inl.h>
-#include <google/protobuf/descriptor.h>
-#include <google/protobuf/generated_message_reflection.h>
-#include <google/protobuf/reflection_ops.h>
-#include <google/protobuf/wire_format.h>
-// This is a temporary google only hack
-#ifdef GOOGLE_PROTOBUF_ENFORCE_UNIQUENESS
-#include "third_party/protobuf/version.h"
-#endif
-// @@protoc_insertion_point(includes)
-
-namespace helloworld {
-class HelloRequestDefaultTypeInternal {
- public:
-  ::google::protobuf::internal::ExplicitlyConstructed<HelloRequest>
-      _instance;
-} _HelloRequest_default_instance_;
-class HelloReplyDefaultTypeInternal {
- public:
-  ::google::protobuf::internal::ExplicitlyConstructed<HelloReply>
-      _instance;
-} _HelloReply_default_instance_;
-}  // namespace helloworld
-namespace protobuf_helloworld_2eproto {
-static void InitDefaultsHelloRequest() {
-  GOOGLE_PROTOBUF_VERIFY_VERSION;
-
-  {
-    void* ptr = &::helloworld::_HelloRequest_default_instance_;
-    new (ptr) ::helloworld::HelloRequest();
-    ::google::protobuf::internal::OnShutdownDestroyMessage(ptr);
-  }
-  ::helloworld::HelloRequest::InitAsDefaultInstance();
-}
-
-::google::protobuf::internal::SCCInfo<0> scc_info_HelloRequest =
-    {{ATOMIC_VAR_INIT(::google::protobuf::internal::SCCInfoBase::kUninitialized), 0, InitDefaultsHelloRequest}, {}};
-
-static void InitDefaultsHelloReply() {
-  GOOGLE_PROTOBUF_VERIFY_VERSION;
-
-  {
-    void* ptr = &::helloworld::_HelloReply_default_instance_;
-    new (ptr) ::helloworld::HelloReply();
-    ::google::protobuf::internal::OnShutdownDestroyMessage(ptr);
-  }
-  ::helloworld::HelloReply::InitAsDefaultInstance();
-}
-
-::google::protobuf::internal::SCCInfo<0> scc_info_HelloReply =
-    {{ATOMIC_VAR_INIT(::google::protobuf::internal::SCCInfoBase::kUninitialized), 0, InitDefaultsHelloReply}, {}};
-
-void InitDefaults() {
-  ::google::protobuf::internal::InitSCC(&scc_info_HelloRequest.base);
-  ::google::protobuf::internal::InitSCC(&scc_info_HelloReply.base);
-}
-
-::google::protobuf::Metadata file_level_metadata[2];
-
-const ::google::protobuf::uint32 TableStruct::offsets[] GOOGLE_PROTOBUF_ATTRIBUTE_SECTION_VARIABLE(protodesc_cold) = {
-  ~0u,  // no _has_bits_
-  GOOGLE_PROTOBUF_GENERATED_MESSAGE_FIELD_OFFSET(::helloworld::HelloRequest, _internal_metadata_),
-  ~0u,  // no _extensions_
-  ~0u,  // no _oneof_case_
-  ~0u,  // no _weak_field_map_
-  GOOGLE_PROTOBUF_GENERATED_MESSAGE_FIELD_OFFSET(::helloworld::HelloRequest, name_),
-  ~0u,  // no _has_bits_
-  GOOGLE_PROTOBUF_GENERATED_MESSAGE_FIELD_OFFSET(::helloworld::HelloReply, _internal_metadata_),
-  ~0u,  // no _extensions_
-  ~0u,  // no _oneof_case_
-  ~0u,  // no _weak_field_map_
-  GOOGLE_PROTOBUF_GENERATED_MESSAGE_FIELD_OFFSET(::helloworld::HelloReply, message_),
-};
-static const ::google::protobuf::internal::MigrationSchema schemas[] GOOGLE_PROTOBUF_ATTRIBUTE_SECTION_VARIABLE(protodesc_cold) = {
-  { 0, -1, sizeof(::helloworld::HelloRequest)},
-  { 6, -1, sizeof(::helloworld::HelloReply)},
-};
-
-static ::google::protobuf::Message const * const file_default_instances[] = {
-  reinterpret_cast<const ::google::protobuf::Message*>(&::helloworld::_HelloRequest_default_instance_),
-  reinterpret_cast<const ::google::protobuf::Message*>(&::helloworld::_HelloReply_default_instance_),
-};
-
-void protobuf_AssignDescriptors() {
-  AddDescriptors();
-  AssignDescriptors(
-      "helloworld.proto", schemas, file_default_instances, TableStruct::offsets,
-      file_level_metadata, NULL, NULL);
-}
-
-void protobuf_AssignDescriptorsOnce() {
-  static ::google::protobuf::internal::once_flag once;
-  ::google::protobuf::internal::call_once(once, protobuf_AssignDescriptors);
-}
-
-void protobuf_RegisterTypes(const ::std::string&) GOOGLE_PROTOBUF_ATTRIBUTE_COLD;
-void protobuf_RegisterTypes(const ::std::string&) {
-  protobuf_AssignDescriptorsOnce();
-  ::google::protobuf::internal::RegisterAllTypes(file_level_metadata, 2);
-}
-
-void AddDescriptorsImpl() {
-  InitDefaults();
-  static const char descriptor[] GOOGLE_PROTOBUF_ATTRIBUTE_SECTION_VARIABLE(protodesc_cold) = {
-      "\n\020helloworld.proto\022\nhelloworld\"\034\n\014HelloR"
-      "equest\022\014\n\004name\030\001 \001(\t\"\035\n\nHelloReply\022\017\n\007me"
-      "ssage\030\001 \001(\t2I\n\007Greeter\022>\n\010SayHello\022\030.hel"
-      "loworld.HelloRequest\032\026.helloworld.HelloR"
-      "eply\"\000B6\n\033io.grpc.examples.helloworldB\017H"
-      "elloWorldProtoP\001\242\002\003HLWb\006proto3"
-  };
-  ::google::protobuf::DescriptorPool::InternalAddGeneratedFile(
-      descriptor, 230);
-  ::google::protobuf::MessageFactory::InternalRegisterGeneratedFile(
-    "helloworld.proto", &protobuf_RegisterTypes);
-}
-
-void AddDescriptors() {
-  static ::google::protobuf::internal::once_flag once;
-  ::google::protobuf::internal::call_once(once, AddDescriptorsImpl);
-}
-// Force AddDescriptors() to be called at dynamic initialization time.
-struct StaticDescriptorInitializer {
-  StaticDescriptorInitializer() {
-    AddDescriptors();
-  }
-} static_descriptor_initializer;
-}  // namespace protobuf_helloworld_2eproto
-namespace helloworld {
-
-// ===================================================================
-
-void HelloRequest::InitAsDefaultInstance() {
-}
-#if !defined(_MSC_VER) || _MSC_VER >= 1900
-const int HelloRequest::kNameFieldNumber;
-#endif  // !defined(_MSC_VER) || _MSC_VER >= 1900
-
-HelloRequest::HelloRequest()
-  : ::google::protobuf::Message(), _internal_metadata_(NULL) {
-  ::google::protobuf::internal::InitSCC(
-      &protobuf_helloworld_2eproto::scc_info_HelloRequest.base);
-  SharedCtor();
-  // @@protoc_insertion_point(constructor:helloworld.HelloRequest)
-}
-HelloRequest::HelloRequest(const HelloRequest& from)
-  : ::google::protobuf::Message(),
-      _internal_metadata_(NULL) {
-  _internal_metadata_.MergeFrom(from._internal_metadata_);
-  name_.UnsafeSetDefault(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-  if (from.name().size() > 0) {
-    name_.AssignWithDefault(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), from.name_);
-  }
-  // @@protoc_insertion_point(copy_constructor:helloworld.HelloRequest)
-}
-
-void HelloRequest::SharedCtor() {
-  name_.UnsafeSetDefault(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-
-HelloRequest::~HelloRequest() {
-  // @@protoc_insertion_point(destructor:helloworld.HelloRequest)
-  SharedDtor();
-}
-
-void HelloRequest::SharedDtor() {
-  name_.DestroyNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-
-void HelloRequest::SetCachedSize(int size) const {
-  _cached_size_.Set(size);
-}
-const ::google::protobuf::Descriptor* HelloRequest::descriptor() {
-  ::protobuf_helloworld_2eproto::protobuf_AssignDescriptorsOnce();
-  return ::protobuf_helloworld_2eproto::file_level_metadata[kIndexInFileMessages].descriptor;
-}
-
-const HelloRequest& HelloRequest::default_instance() {
-  ::google::protobuf::internal::InitSCC(&protobuf_helloworld_2eproto::scc_info_HelloRequest.base);
-  return *internal_default_instance();
-}
-
-
-void HelloRequest::Clear() {
-// @@protoc_insertion_point(message_clear_start:helloworld.HelloRequest)
-  ::google::protobuf::uint32 cached_has_bits = 0;
-  // Prevent compiler warnings about cached_has_bits being unused
-  (void) cached_has_bits;
-
-  name_.ClearToEmptyNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-  _internal_metadata_.Clear();
-}
-
-bool HelloRequest::MergePartialFromCodedStream(
-    ::google::protobuf::io::CodedInputStream* input) {
-#define DO_(EXPRESSION) if (!GOOGLE_PREDICT_TRUE(EXPRESSION)) goto failure
-  ::google::protobuf::uint32 tag;
-  // @@protoc_insertion_point(parse_start:helloworld.HelloRequest)
-  for (;;) {
-    ::std::pair<::google::protobuf::uint32, bool> p = input->ReadTagWithCutoffNoLastTag(127u);
-    tag = p.first;
-    if (!p.second) goto handle_unusual;
-    switch (::google::protobuf::internal::WireFormatLite::GetTagFieldNumber(tag)) {
-      // string name = 1;
-      case 1: {
-        if (static_cast< ::google::protobuf::uint8>(tag) ==
-            static_cast< ::google::protobuf::uint8>(10u /* 10 & 0xFF */)) {
-          DO_(::google::protobuf::internal::WireFormatLite::ReadString(
-                input, this->mutable_name()));
-          DO_(::google::protobuf::internal::WireFormatLite::VerifyUtf8String(
-            this->name().data(), static_cast<int>(this->name().length()),
-            ::google::protobuf::internal::WireFormatLite::PARSE,
-            "helloworld.HelloRequest.name"));
-        } else {
-          goto handle_unusual;
-        }
-        break;
-      }
-
-      default: {
-      handle_unusual:
-        if (tag == 0) {
-          goto success;
-        }
-        DO_(::google::protobuf::internal::WireFormat::SkipField(
-              input, tag, _internal_metadata_.mutable_unknown_fields()));
-        break;
-      }
-    }
-  }
-success:
-  // @@protoc_insertion_point(parse_success:helloworld.HelloRequest)
-  return true;
-failure:
-  // @@protoc_insertion_point(parse_failure:helloworld.HelloRequest)
-  return false;
-#undef DO_
-}
-
-void HelloRequest::SerializeWithCachedSizes(
-    ::google::protobuf::io::CodedOutputStream* output) const {
-  // @@protoc_insertion_point(serialize_start:helloworld.HelloRequest)
-  ::google::protobuf::uint32 cached_has_bits = 0;
-  (void) cached_has_bits;
-
-  // string name = 1;
-  if (this->name().size() > 0) {
-    ::google::protobuf::internal::WireFormatLite::VerifyUtf8String(
-      this->name().data(), static_cast<int>(this->name().length()),
-      ::google::protobuf::internal::WireFormatLite::SERIALIZE,
-      "helloworld.HelloRequest.name");
-    ::google::protobuf::internal::WireFormatLite::WriteStringMaybeAliased(
-      1, this->name(), output);
-  }
-
-  if ((_internal_metadata_.have_unknown_fields() &&  ::google::protobuf::internal::GetProto3PreserveUnknownsDefault())) {
-    ::google::protobuf::internal::WireFormat::SerializeUnknownFields(
-        (::google::protobuf::internal::GetProto3PreserveUnknownsDefault()   ? _internal_metadata_.unknown_fields()   : _internal_metadata_.default_instance()), output);
-  }
-  // @@protoc_insertion_point(serialize_end:helloworld.HelloRequest)
-}
-
-::google::protobuf::uint8* HelloRequest::InternalSerializeWithCachedSizesToArray(
-    bool deterministic, ::google::protobuf::uint8* target) const {
-  (void)deterministic; // Unused
-  // @@protoc_insertion_point(serialize_to_array_start:helloworld.HelloRequest)
-  ::google::protobuf::uint32 cached_has_bits = 0;
-  (void) cached_has_bits;
-
-  // string name = 1;
-  if (this->name().size() > 0) {
-    ::google::protobuf::internal::WireFormatLite::VerifyUtf8String(
-      this->name().data(), static_cast<int>(this->name().length()),
-      ::google::protobuf::internal::WireFormatLite::SERIALIZE,
-      "helloworld.HelloRequest.name");
-    target =
-      ::google::protobuf::internal::WireFormatLite::WriteStringToArray(
-        1, this->name(), target);
-  }
-
-  if ((_internal_metadata_.have_unknown_fields() &&  ::google::protobuf::internal::GetProto3PreserveUnknownsDefault())) {
-    target = ::google::protobuf::internal::WireFormat::SerializeUnknownFieldsToArray(
-        (::google::protobuf::internal::GetProto3PreserveUnknownsDefault()   ? _internal_metadata_.unknown_fields()   : _internal_metadata_.default_instance()), target);
-  }
-  // @@protoc_insertion_point(serialize_to_array_end:helloworld.HelloRequest)
-  return target;
-}
-
-size_t HelloRequest::ByteSizeLong() const {
-// @@protoc_insertion_point(message_byte_size_start:helloworld.HelloRequest)
-  size_t total_size = 0;
-
-  if ((_internal_metadata_.have_unknown_fields() &&  ::google::protobuf::internal::GetProto3PreserveUnknownsDefault())) {
-    total_size +=
-      ::google::protobuf::internal::WireFormat::ComputeUnknownFieldsSize(
-        (::google::protobuf::internal::GetProto3PreserveUnknownsDefault()   ? _internal_metadata_.unknown_fields()   : _internal_metadata_.default_instance()));
-  }
-  // string name = 1;
-  if (this->name().size() > 0) {
-    total_size += 1 +
-      ::google::protobuf::internal::WireFormatLite::StringSize(
-        this->name());
-  }
-
-  int cached_size = ::google::protobuf::internal::ToCachedSize(total_size);
-  SetCachedSize(cached_size);
-  return total_size;
-}
-
-void HelloRequest::MergeFrom(const ::google::protobuf::Message& from) {
-// @@protoc_insertion_point(generalized_merge_from_start:helloworld.HelloRequest)
-  GOOGLE_DCHECK_NE(&from, this);
-  const HelloRequest* source =
-      ::google::protobuf::internal::DynamicCastToGenerated<const HelloRequest>(
-          &from);
-  if (source == NULL) {
-  // @@protoc_insertion_point(generalized_merge_from_cast_fail:helloworld.HelloRequest)
-    ::google::protobuf::internal::ReflectionOps::Merge(from, this);
-  } else {
-  // @@protoc_insertion_point(generalized_merge_from_cast_success:helloworld.HelloRequest)
-    MergeFrom(*source);
-  }
-}
-
-void HelloRequest::MergeFrom(const HelloRequest& from) {
-// @@protoc_insertion_point(class_specific_merge_from_start:helloworld.HelloRequest)
-  GOOGLE_DCHECK_NE(&from, this);
-  _internal_metadata_.MergeFrom(from._internal_metadata_);
-  ::google::protobuf::uint32 cached_has_bits = 0;
-  (void) cached_has_bits;
-
-  if (from.name().size() > 0) {
-
-    name_.AssignWithDefault(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), from.name_);
-  }
-}
-
-void HelloRequest::CopyFrom(const ::google::protobuf::Message& from) {
-// @@protoc_insertion_point(generalized_copy_from_start:helloworld.HelloRequest)
-  if (&from == this) return;
-  Clear();
-  MergeFrom(from);
-}
-
-void HelloRequest::CopyFrom(const HelloRequest& from) {
-// @@protoc_insertion_point(class_specific_copy_from_start:helloworld.HelloRequest)
-  if (&from == this) return;
-  Clear();
-  MergeFrom(from);
-}
-
-bool HelloRequest::IsInitialized() const {
-  return true;
-}
-
-void HelloRequest::Swap(HelloRequest* other) {
-  if (other == this) return;
-  InternalSwap(other);
-}
-void HelloRequest::InternalSwap(HelloRequest* other) {
-  using std::swap;
-  name_.Swap(&other->name_, &::google::protobuf::internal::GetEmptyStringAlreadyInited(),
-    GetArenaNoVirtual());
-  _internal_metadata_.Swap(&other->_internal_metadata_);
-}
-
-::google::protobuf::Metadata HelloRequest::GetMetadata() const {
-  protobuf_helloworld_2eproto::protobuf_AssignDescriptorsOnce();
-  return ::protobuf_helloworld_2eproto::file_level_metadata[kIndexInFileMessages];
-}
-
-
-// ===================================================================
-
-void HelloReply::InitAsDefaultInstance() {
-}
-#if !defined(_MSC_VER) || _MSC_VER >= 1900
-const int HelloReply::kMessageFieldNumber;
-#endif  // !defined(_MSC_VER) || _MSC_VER >= 1900
-
-HelloReply::HelloReply()
-  : ::google::protobuf::Message(), _internal_metadata_(NULL) {
-  ::google::protobuf::internal::InitSCC(
-      &protobuf_helloworld_2eproto::scc_info_HelloReply.base);
-  SharedCtor();
-  // @@protoc_insertion_point(constructor:helloworld.HelloReply)
-}
-HelloReply::HelloReply(const HelloReply& from)
-  : ::google::protobuf::Message(),
-      _internal_metadata_(NULL) {
-  _internal_metadata_.MergeFrom(from._internal_metadata_);
-  message_.UnsafeSetDefault(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-  if (from.message().size() > 0) {
-    message_.AssignWithDefault(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), from.message_);
-  }
-  // @@protoc_insertion_point(copy_constructor:helloworld.HelloReply)
-}
-
-void HelloReply::SharedCtor() {
-  message_.UnsafeSetDefault(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-
-HelloReply::~HelloReply() {
-  // @@protoc_insertion_point(destructor:helloworld.HelloReply)
-  SharedDtor();
-}
-
-void HelloReply::SharedDtor() {
-  message_.DestroyNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-
-void HelloReply::SetCachedSize(int size) const {
-  _cached_size_.Set(size);
-}
-const ::google::protobuf::Descriptor* HelloReply::descriptor() {
-  ::protobuf_helloworld_2eproto::protobuf_AssignDescriptorsOnce();
-  return ::protobuf_helloworld_2eproto::file_level_metadata[kIndexInFileMessages].descriptor;
-}
-
-const HelloReply& HelloReply::default_instance() {
-  ::google::protobuf::internal::InitSCC(&protobuf_helloworld_2eproto::scc_info_HelloReply.base);
-  return *internal_default_instance();
-}
-
-
-void HelloReply::Clear() {
-// @@protoc_insertion_point(message_clear_start:helloworld.HelloReply)
-  ::google::protobuf::uint32 cached_has_bits = 0;
-  // Prevent compiler warnings about cached_has_bits being unused
-  (void) cached_has_bits;
-
-  message_.ClearToEmptyNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-  _internal_metadata_.Clear();
-}
-
-bool HelloReply::MergePartialFromCodedStream(
-    ::google::protobuf::io::CodedInputStream* input) {
-#define DO_(EXPRESSION) if (!GOOGLE_PREDICT_TRUE(EXPRESSION)) goto failure
-  ::google::protobuf::uint32 tag;
-  // @@protoc_insertion_point(parse_start:helloworld.HelloReply)
-  for (;;) {
-    ::std::pair<::google::protobuf::uint32, bool> p = input->ReadTagWithCutoffNoLastTag(127u);
-    tag = p.first;
-    if (!p.second) goto handle_unusual;
-    switch (::google::protobuf::internal::WireFormatLite::GetTagFieldNumber(tag)) {
-      // string message = 1;
-      case 1: {
-        if (static_cast< ::google::protobuf::uint8>(tag) ==
-            static_cast< ::google::protobuf::uint8>(10u /* 10 & 0xFF */)) {
-          DO_(::google::protobuf::internal::WireFormatLite::ReadString(
-                input, this->mutable_message()));
-          DO_(::google::protobuf::internal::WireFormatLite::VerifyUtf8String(
-            this->message().data(), static_cast<int>(this->message().length()),
-            ::google::protobuf::internal::WireFormatLite::PARSE,
-            "helloworld.HelloReply.message"));
-        } else {
-          goto handle_unusual;
-        }
-        break;
-      }
-
-      default: {
-      handle_unusual:
-        if (tag == 0) {
-          goto success;
-        }
-        DO_(::google::protobuf::internal::WireFormat::SkipField(
-              input, tag, _internal_metadata_.mutable_unknown_fields()));
-        break;
-      }
-    }
-  }
-success:
-  // @@protoc_insertion_point(parse_success:helloworld.HelloReply)
-  return true;
-failure:
-  // @@protoc_insertion_point(parse_failure:helloworld.HelloReply)
-  return false;
-#undef DO_
-}
-
-void HelloReply::SerializeWithCachedSizes(
-    ::google::protobuf::io::CodedOutputStream* output) const {
-  // @@protoc_insertion_point(serialize_start:helloworld.HelloReply)
-  ::google::protobuf::uint32 cached_has_bits = 0;
-  (void) cached_has_bits;
-
-  // string message = 1;
-  if (this->message().size() > 0) {
-    ::google::protobuf::internal::WireFormatLite::VerifyUtf8String(
-      this->message().data(), static_cast<int>(this->message().length()),
-      ::google::protobuf::internal::WireFormatLite::SERIALIZE,
-      "helloworld.HelloReply.message");
-    ::google::protobuf::internal::WireFormatLite::WriteStringMaybeAliased(
-      1, this->message(), output);
-  }
-
-  if ((_internal_metadata_.have_unknown_fields() &&  ::google::protobuf::internal::GetProto3PreserveUnknownsDefault())) {
-    ::google::protobuf::internal::WireFormat::SerializeUnknownFields(
-        (::google::protobuf::internal::GetProto3PreserveUnknownsDefault()   ? _internal_metadata_.unknown_fields()   : _internal_metadata_.default_instance()), output);
-  }
-  // @@protoc_insertion_point(serialize_end:helloworld.HelloReply)
-}
-
-::google::protobuf::uint8* HelloReply::InternalSerializeWithCachedSizesToArray(
-    bool deterministic, ::google::protobuf::uint8* target) const {
-  (void)deterministic; // Unused
-  // @@protoc_insertion_point(serialize_to_array_start:helloworld.HelloReply)
-  ::google::protobuf::uint32 cached_has_bits = 0;
-  (void) cached_has_bits;
-
-  // string message = 1;
-  if (this->message().size() > 0) {
-    ::google::protobuf::internal::WireFormatLite::VerifyUtf8String(
-      this->message().data(), static_cast<int>(this->message().length()),
-      ::google::protobuf::internal::WireFormatLite::SERIALIZE,
-      "helloworld.HelloReply.message");
-    target =
-      ::google::protobuf::internal::WireFormatLite::WriteStringToArray(
-        1, this->message(), target);
-  }
-
-  if ((_internal_metadata_.have_unknown_fields() &&  ::google::protobuf::internal::GetProto3PreserveUnknownsDefault())) {
-    target = ::google::protobuf::internal::WireFormat::SerializeUnknownFieldsToArray(
-        (::google::protobuf::internal::GetProto3PreserveUnknownsDefault()   ? _internal_metadata_.unknown_fields()   : _internal_metadata_.default_instance()), target);
-  }
-  // @@protoc_insertion_point(serialize_to_array_end:helloworld.HelloReply)
-  return target;
-}
-
-size_t HelloReply::ByteSizeLong() const {
-// @@protoc_insertion_point(message_byte_size_start:helloworld.HelloReply)
-  size_t total_size = 0;
-
-  if ((_internal_metadata_.have_unknown_fields() &&  ::google::protobuf::internal::GetProto3PreserveUnknownsDefault())) {
-    total_size +=
-      ::google::protobuf::internal::WireFormat::ComputeUnknownFieldsSize(
-        (::google::protobuf::internal::GetProto3PreserveUnknownsDefault()   ? _internal_metadata_.unknown_fields()   : _internal_metadata_.default_instance()));
-  }
-  // string message = 1;
-  if (this->message().size() > 0) {
-    total_size += 1 +
-      ::google::protobuf::internal::WireFormatLite::StringSize(
-        this->message());
-  }
-
-  int cached_size = ::google::protobuf::internal::ToCachedSize(total_size);
-  SetCachedSize(cached_size);
-  return total_size;
-}
-
-void HelloReply::MergeFrom(const ::google::protobuf::Message& from) {
-// @@protoc_insertion_point(generalized_merge_from_start:helloworld.HelloReply)
-  GOOGLE_DCHECK_NE(&from, this);
-  const HelloReply* source =
-      ::google::protobuf::internal::DynamicCastToGenerated<const HelloReply>(
-          &from);
-  if (source == NULL) {
-  // @@protoc_insertion_point(generalized_merge_from_cast_fail:helloworld.HelloReply)
-    ::google::protobuf::internal::ReflectionOps::Merge(from, this);
-  } else {
-  // @@protoc_insertion_point(generalized_merge_from_cast_success:helloworld.HelloReply)
-    MergeFrom(*source);
-  }
-}
-
-void HelloReply::MergeFrom(const HelloReply& from) {
-// @@protoc_insertion_point(class_specific_merge_from_start:helloworld.HelloReply)
-  GOOGLE_DCHECK_NE(&from, this);
-  _internal_metadata_.MergeFrom(from._internal_metadata_);
-  ::google::protobuf::uint32 cached_has_bits = 0;
-  (void) cached_has_bits;
-
-  if (from.message().size() > 0) {
-
-    message_.AssignWithDefault(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), from.message_);
-  }
-}
-
-void HelloReply::CopyFrom(const ::google::protobuf::Message& from) {
-// @@protoc_insertion_point(generalized_copy_from_start:helloworld.HelloReply)
-  if (&from == this) return;
-  Clear();
-  MergeFrom(from);
-}
-
-void HelloReply::CopyFrom(const HelloReply& from) {
-// @@protoc_insertion_point(class_specific_copy_from_start:helloworld.HelloReply)
-  if (&from == this) return;
-  Clear();
-  MergeFrom(from);
-}
-
-bool HelloReply::IsInitialized() const {
-  return true;
-}
-
-void HelloReply::Swap(HelloReply* other) {
-  if (other == this) return;
-  InternalSwap(other);
-}
-void HelloReply::InternalSwap(HelloReply* other) {
-  using std::swap;
-  message_.Swap(&other->message_, &::google::protobuf::internal::GetEmptyStringAlreadyInited(),
-    GetArenaNoVirtual());
-  _internal_metadata_.Swap(&other->_internal_metadata_);
-}
-
-::google::protobuf::Metadata HelloReply::GetMetadata() const {
-  protobuf_helloworld_2eproto::protobuf_AssignDescriptorsOnce();
-  return ::protobuf_helloworld_2eproto::file_level_metadata[kIndexInFileMessages];
-}
-
-
-// @@protoc_insertion_point(namespace_scope)
-}  // namespace helloworld
-namespace google {
-namespace protobuf {
-template<> GOOGLE_PROTOBUF_ATTRIBUTE_NOINLINE ::helloworld::HelloRequest* Arena::CreateMaybeMessage< ::helloworld::HelloRequest >(Arena* arena) {
-  return Arena::CreateInternal< ::helloworld::HelloRequest >(arena);
-}
-template<> GOOGLE_PROTOBUF_ATTRIBUTE_NOINLINE ::helloworld::HelloReply* Arena::CreateMaybeMessage< ::helloworld::HelloReply >(Arena* arena) {
-  return Arena::CreateInternal< ::helloworld::HelloReply >(arena);
-}
-}  // namespace protobuf
-}  // namespace google
-
-// @@protoc_insertion_point(global_scope)
diff --git a/examples/cpp/metadata/helloworld.pb.h b/examples/cpp/metadata/helloworld.pb.h
deleted file mode 100644
index 57f6817e31..0000000000
--- a/examples/cpp/metadata/helloworld.pb.h
+++ /dev/null
@@ -1,419 +0,0 @@
-// Generated by the protocol buffer compiler.  DO NOT EDIT!
-// source: helloworld.proto
-
-#ifndef PROTOBUF_INCLUDED_helloworld_2eproto
-#define PROTOBUF_INCLUDED_helloworld_2eproto
-
-#include <string>
-
-#include <google/protobuf/stubs/common.h>
-
-#if GOOGLE_PROTOBUF_VERSION < 3006001
-#error This file was generated by a newer version of protoc which is
-#error incompatible with your Protocol Buffer headers.  Please update
-#error your headers.
-#endif
-#if 3006001 < GOOGLE_PROTOBUF_MIN_PROTOC_VERSION
-#error This file was generated by an older version of protoc which is
-#error incompatible with your Protocol Buffer headers.  Please
-#error regenerate this file with a newer version of protoc.
-#endif
-
-#include <google/protobuf/io/coded_stream.h>
-#include <google/protobuf/arena.h>
-#include <google/protobuf/arenastring.h>
-#include <google/protobuf/generated_message_table_driven.h>
-#include <google/protobuf/generated_message_util.h>
-#include <google/protobuf/inlined_string_field.h>
-#include <google/protobuf/metadata.h>
-#include <google/protobuf/message.h>
-#include <google/protobuf/repeated_field.h>  // IWYU pragma: export
-#include <google/protobuf/extension_set.h>  // IWYU pragma: export
-#include <google/protobuf/unknown_field_set.h>
-// @@protoc_insertion_point(includes)
-#define PROTOBUF_INTERNAL_EXPORT_protobuf_helloworld_2eproto 
-
-namespace protobuf_helloworld_2eproto {
-// Internal implementation detail -- do not use these members.
-struct TableStruct {
-  static const ::google::protobuf::internal::ParseTableField entries[];
-  static const ::google::protobuf::internal::AuxillaryParseTableField aux[];
-  static const ::google::protobuf::internal::ParseTable schema[2];
-  static const ::google::protobuf::internal::FieldMetadata field_metadata[];
-  static const ::google::protobuf::internal::SerializationTable serialization_table[];
-  static const ::google::protobuf::uint32 offsets[];
-};
-void AddDescriptors();
-}  // namespace protobuf_helloworld_2eproto
-namespace helloworld {
-class HelloReply;
-class HelloReplyDefaultTypeInternal;
-extern HelloReplyDefaultTypeInternal _HelloReply_default_instance_;
-class HelloRequest;
-class HelloRequestDefaultTypeInternal;
-extern HelloRequestDefaultTypeInternal _HelloRequest_default_instance_;
-}  // namespace helloworld
-namespace google {
-namespace protobuf {
-template<> ::helloworld::HelloReply* Arena::CreateMaybeMessage<::helloworld::HelloReply>(Arena*);
-template<> ::helloworld::HelloRequest* Arena::CreateMaybeMessage<::helloworld::HelloRequest>(Arena*);
-}  // namespace protobuf
-}  // namespace google
-namespace helloworld {
-
-// ===================================================================
-
-class HelloRequest : public ::google::protobuf::Message /* @@protoc_insertion_point(class_definition:helloworld.HelloRequest) */ {
- public:
-  HelloRequest();
-  virtual ~HelloRequest();
-
-  HelloRequest(const HelloRequest& from);
-
-  inline HelloRequest& operator=(const HelloRequest& from) {
-    CopyFrom(from);
-    return *this;
-  }
-  #if LANG_CXX11
-  HelloRequest(HelloRequest&& from) noexcept
-    : HelloRequest() {
-    *this = ::std::move(from);
-  }
-
-  inline HelloRequest& operator=(HelloRequest&& from) noexcept {
-    if (GetArenaNoVirtual() == from.GetArenaNoVirtual()) {
-      if (this != &from) InternalSwap(&from);
-    } else {
-      CopyFrom(from);
-    }
-    return *this;
-  }
-  #endif
-  static const ::google::protobuf::Descriptor* descriptor();
-  static const HelloRequest& default_instance();
-
-  static void InitAsDefaultInstance();  // FOR INTERNAL USE ONLY
-  static inline const HelloRequest* internal_default_instance() {
-    return reinterpret_cast<const HelloRequest*>(
-               &_HelloRequest_default_instance_);
-  }
-  static constexpr int kIndexInFileMessages =
-    0;
-
-  void Swap(HelloRequest* other);
-  friend void swap(HelloRequest& a, HelloRequest& b) {
-    a.Swap(&b);
-  }
-
-  // implements Message ----------------------------------------------
-
-  inline HelloRequest* New() const final {
-    return CreateMaybeMessage<HelloRequest>(NULL);
-  }
-
-  HelloRequest* New(::google::protobuf::Arena* arena) const final {
-    return CreateMaybeMessage<HelloRequest>(arena);
-  }
-  void CopyFrom(const ::google::protobuf::Message& from) final;
-  void MergeFrom(const ::google::protobuf::Message& from) final;
-  void CopyFrom(const HelloRequest& from);
-  void MergeFrom(const HelloRequest& from);
-  void Clear() final;
-  bool IsInitialized() const final;
-
-  size_t ByteSizeLong() const final;
-  bool MergePartialFromCodedStream(
-      ::google::protobuf::io::CodedInputStream* input) final;
-  void SerializeWithCachedSizes(
-      ::google::protobuf::io::CodedOutputStream* output) const final;
-  ::google::protobuf::uint8* InternalSerializeWithCachedSizesToArray(
-      bool deterministic, ::google::protobuf::uint8* target) const final;
-  int GetCachedSize() const final { return _cached_size_.Get(); }
-
-  private:
-  void SharedCtor();
-  void SharedDtor();
-  void SetCachedSize(int size) const final;
-  void InternalSwap(HelloRequest* other);
-  private:
-  inline ::google::protobuf::Arena* GetArenaNoVirtual() const {
-    return NULL;
-  }
-  inline void* MaybeArenaPtr() const {
-    return NULL;
-  }
-  public:
-
-  ::google::protobuf::Metadata GetMetadata() const final;
-
-  // nested types ----------------------------------------------------
-
-  // accessors -------------------------------------------------------
-
-  // string name = 1;
-  void clear_name();
-  static const int kNameFieldNumber = 1;
-  const ::std::string& name() const;
-  void set_name(const ::std::string& value);
-  #if LANG_CXX11
-  void set_name(::std::string&& value);
-  #endif
-  void set_name(const char* value);
-  void set_name(const char* value, size_t size);
-  ::std::string* mutable_name();
-  ::std::string* release_name();
-  void set_allocated_name(::std::string* name);
-
-  // @@protoc_insertion_point(class_scope:helloworld.HelloRequest)
- private:
-
-  ::google::protobuf::internal::InternalMetadataWithArena _internal_metadata_;
-  ::google::protobuf::internal::ArenaStringPtr name_;
-  mutable ::google::protobuf::internal::CachedSize _cached_size_;
-  friend struct ::protobuf_helloworld_2eproto::TableStruct;
-};
-// -------------------------------------------------------------------
-
-class HelloReply : public ::google::protobuf::Message /* @@protoc_insertion_point(class_definition:helloworld.HelloReply) */ {
- public:
-  HelloReply();
-  virtual ~HelloReply();
-
-  HelloReply(const HelloReply& from);
-
-  inline HelloReply& operator=(const HelloReply& from) {
-    CopyFrom(from);
-    return *this;
-  }
-  #if LANG_CXX11
-  HelloReply(HelloReply&& from) noexcept
-    : HelloReply() {
-    *this = ::std::move(from);
-  }
-
-  inline HelloReply& operator=(HelloReply&& from) noexcept {
-    if (GetArenaNoVirtual() == from.GetArenaNoVirtual()) {
-      if (this != &from) InternalSwap(&from);
-    } else {
-      CopyFrom(from);
-    }
-    return *this;
-  }
-  #endif
-  static const ::google::protobuf::Descriptor* descriptor();
-  static const HelloReply& default_instance();
-
-  static void InitAsDefaultInstance();  // FOR INTERNAL USE ONLY
-  static inline const HelloReply* internal_default_instance() {
-    return reinterpret_cast<const HelloReply*>(
-               &_HelloReply_default_instance_);
-  }
-  static constexpr int kIndexInFileMessages =
-    1;
-
-  void Swap(HelloReply* other);
-  friend void swap(HelloReply& a, HelloReply& b) {
-    a.Swap(&b);
-  }
-
-  // implements Message ----------------------------------------------
-
-  inline HelloReply* New() const final {
-    return CreateMaybeMessage<HelloReply>(NULL);
-  }
-
-  HelloReply* New(::google::protobuf::Arena* arena) const final {
-    return CreateMaybeMessage<HelloReply>(arena);
-  }
-  void CopyFrom(const ::google::protobuf::Message& from) final;
-  void MergeFrom(const ::google::protobuf::Message& from) final;
-  void CopyFrom(const HelloReply& from);
-  void MergeFrom(const HelloReply& from);
-  void Clear() final;
-  bool IsInitialized() const final;
-
-  size_t ByteSizeLong() const final;
-  bool MergePartialFromCodedStream(
-      ::google::protobuf::io::CodedInputStream* input) final;
-  void SerializeWithCachedSizes(
-      ::google::protobuf::io::CodedOutputStream* output) const final;
-  ::google::protobuf::uint8* InternalSerializeWithCachedSizesToArray(
-      bool deterministic, ::google::protobuf::uint8* target) const final;
-  int GetCachedSize() const final { return _cached_size_.Get(); }
-
-  private:
-  void SharedCtor();
-  void SharedDtor();
-  void SetCachedSize(int size) const final;
-  void InternalSwap(HelloReply* other);
-  private:
-  inline ::google::protobuf::Arena* GetArenaNoVirtual() const {
-    return NULL;
-  }
-  inline void* MaybeArenaPtr() const {
-    return NULL;
-  }
-  public:
-
-  ::google::protobuf::Metadata GetMetadata() const final;
-
-  // nested types ----------------------------------------------------
-
-  // accessors -------------------------------------------------------
-
-  // string message = 1;
-  void clear_message();
-  static const int kMessageFieldNumber = 1;
-  const ::std::string& message() const;
-  void set_message(const ::std::string& value);
-  #if LANG_CXX11
-  void set_message(::std::string&& value);
-  #endif
-  void set_message(const char* value);
-  void set_message(const char* value, size_t size);
-  ::std::string* mutable_message();
-  ::std::string* release_message();
-  void set_allocated_message(::std::string* message);
-
-  // @@protoc_insertion_point(class_scope:helloworld.HelloReply)
- private:
-
-  ::google::protobuf::internal::InternalMetadataWithArena _internal_metadata_;
-  ::google::protobuf::internal::ArenaStringPtr message_;
-  mutable ::google::protobuf::internal::CachedSize _cached_size_;
-  friend struct ::protobuf_helloworld_2eproto::TableStruct;
-};
-// ===================================================================
-
-
-// ===================================================================
-
-#ifdef __GNUC__
-  #pragma GCC diagnostic push
-  #pragma GCC diagnostic ignored "-Wstrict-aliasing"
-#endif  // __GNUC__
-// HelloRequest
-
-// string name = 1;
-inline void HelloRequest::clear_name() {
-  name_.ClearToEmptyNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-inline const ::std::string& HelloRequest::name() const {
-  // @@protoc_insertion_point(field_get:helloworld.HelloRequest.name)
-  return name_.GetNoArena();
-}
-inline void HelloRequest::set_name(const ::std::string& value) {
-  
-  name_.SetNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), value);
-  // @@protoc_insertion_point(field_set:helloworld.HelloRequest.name)
-}
-#if LANG_CXX11
-inline void HelloRequest::set_name(::std::string&& value) {
-  
-  name_.SetNoArena(
-    &::google::protobuf::internal::GetEmptyStringAlreadyInited(), ::std::move(value));
-  // @@protoc_insertion_point(field_set_rvalue:helloworld.HelloRequest.name)
-}
-#endif
-inline void HelloRequest::set_name(const char* value) {
-  GOOGLE_DCHECK(value != NULL);
-  
-  name_.SetNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), ::std::string(value));
-  // @@protoc_insertion_point(field_set_char:helloworld.HelloRequest.name)
-}
-inline void HelloRequest::set_name(const char* value, size_t size) {
-  
-  name_.SetNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited(),
-      ::std::string(reinterpret_cast<const char*>(value), size));
-  // @@protoc_insertion_point(field_set_pointer:helloworld.HelloRequest.name)
-}
-inline ::std::string* HelloRequest::mutable_name() {
-  
-  // @@protoc_insertion_point(field_mutable:helloworld.HelloRequest.name)
-  return name_.MutableNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-inline ::std::string* HelloRequest::release_name() {
-  // @@protoc_insertion_point(field_release:helloworld.HelloRequest.name)
-  
-  return name_.ReleaseNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-inline void HelloRequest::set_allocated_name(::std::string* name) {
-  if (name != NULL) {
-    
-  } else {
-    
-  }
-  name_.SetAllocatedNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), name);
-  // @@protoc_insertion_point(field_set_allocated:helloworld.HelloRequest.name)
-}
-
-// -------------------------------------------------------------------
-
-// HelloReply
-
-// string message = 1;
-inline void HelloReply::clear_message() {
-  message_.ClearToEmptyNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-inline const ::std::string& HelloReply::message() const {
-  // @@protoc_insertion_point(field_get:helloworld.HelloReply.message)
-  return message_.GetNoArena();
-}
-inline void HelloReply::set_message(const ::std::string& value) {
-  
-  message_.SetNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), value);
-  // @@protoc_insertion_point(field_set:helloworld.HelloReply.message)
-}
-#if LANG_CXX11
-inline void HelloReply::set_message(::std::string&& value) {
-  
-  message_.SetNoArena(
-    &::google::protobuf::internal::GetEmptyStringAlreadyInited(), ::std::move(value));
-  // @@protoc_insertion_point(field_set_rvalue:helloworld.HelloReply.message)
-}
-#endif
-inline void HelloReply::set_message(const char* value) {
-  GOOGLE_DCHECK(value != NULL);
-  
-  message_.SetNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), ::std::string(value));
-  // @@protoc_insertion_point(field_set_char:helloworld.HelloReply.message)
-}
-inline void HelloReply::set_message(const char* value, size_t size) {
-  
-  message_.SetNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited(),
-      ::std::string(reinterpret_cast<const char*>(value), size));
-  // @@protoc_insertion_point(field_set_pointer:helloworld.HelloReply.message)
-}
-inline ::std::string* HelloReply::mutable_message() {
-  
-  // @@protoc_insertion_point(field_mutable:helloworld.HelloReply.message)
-  return message_.MutableNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-inline ::std::string* HelloReply::release_message() {
-  // @@protoc_insertion_point(field_release:helloworld.HelloReply.message)
-  
-  return message_.ReleaseNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited());
-}
-inline void HelloReply::set_allocated_message(::std::string* message) {
-  if (message != NULL) {
-    
-  } else {
-    
-  }
-  message_.SetAllocatedNoArena(&::google::protobuf::internal::GetEmptyStringAlreadyInited(), message);
-  // @@protoc_insertion_point(field_set_allocated:helloworld.HelloReply.message)
-}
-
-#ifdef __GNUC__
-  #pragma GCC diagnostic pop
-#endif  // __GNUC__
-// -------------------------------------------------------------------
-
-
-// @@protoc_insertion_point(namespace_scope)
-
-}  // namespace helloworld
-
-// @@protoc_insertion_point(global_scope)
-
-#endif  // PROTOBUF_INCLUDED_helloworld_2eproto
diff --git a/examples/cpp/metadata/helloworld.pb.o b/examples/cpp/metadata/helloworld.pb.o
deleted file mode 100644
index 85671e8aaa..0000000000
--- a/examples/cpp/metadata/helloworld.pb.o
+++ /dev/null