Grpc Note

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bazel build :all

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syntax = "proto3";

option java_multiple_files = true;
option java_package = "io.grpc.examples.routeguide";
option java_outer_classname = "RouteGuideProto";
option objc_class_prefix = "RTG";

package routeguide;

// Interface exported by the server.
service RouteGuide {
  // A simple RPC.
  //
  // Obtains the feature at a given position.
  //
  // A feature with an empty name is returned if there's no feature at the given
  // position.
  rpc GetFeature(Point) returns (Feature) {}

  // A server-to-client streaming RPC.
  //
  // Obtains the Features available within the given Rectangle.  Results are
  // streamed rather than returned at once (e.g. in a response message with a
  // repeated field), as the rectangle may cover a large area and contain a
  // huge number of features.
  rpc ListFeatures(Rectangle) returns (stream Feature) {}

  // A client-to-server streaming RPC.
  //
  // Accepts a stream of Points on a route being traversed, returning a
  // RouteSummary when traversal is completed.
  rpc RecordRoute(stream Point) returns (RouteSummary) {}

  // A Bidirectional streaming RPC.
  //
  // Accepts a stream of RouteNotes sent while a route is being traversed,
  // while receiving other RouteNotes (e.g. from other users).
  rpc RouteChat(stream RouteNote) returns (stream RouteNote) {}
}

// Points are represented as latitude-longitude pairs in the E7 representation
// (degrees multiplied by 10**7 and rounded to the nearest integer).
// Latitudes should be in the range +/- 90 degrees and longitude should be in
// the range +/- 180 degrees (inclusive).
message Point {
  int32 latitude = 1;
  int32 longitude = 2;
}

// A latitude-longitude rectangle, represented as two diagonally opposite
// points "lo" and "hi".
message Rectangle {
  // One corner of the rectangle.
  Point lo = 1;

  // The other corner of the rectangle.
  Point hi = 2;
}

// A feature names something at a given point.
//
// If a feature could not be named, the name is empty.
message Feature {
  // The name of the feature.
  string name = 1;

  // The point where the feature is detected.
  Point location = 2;
}

// A RouteNote is a message sent while at a given point.
message RouteNote {
  // The location from which the message is sent.
  Point location = 1;

  // The message to be sent.
  string message = 2;
}

// A RouteSummary is received in response to a RecordRoute rpc.
//
// It contains the number of individual points received, the number of
// detected features, and the total distance covered as the cumulative sum of
// the distance between each point.
message RouteSummary {
  // The number of points received.
  int32 point_count = 1;

  // The number of known features passed while traversing the route.
  int32 feature_count = 2;

  // The distance covered in metres.
  int32 distance = 3;

  // The duration of the traversal in seconds.
  int32 elapsed_time = 4;
}

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# --plugin=protoc-gen-grpc=`which grpc_cpp_plugin` 这里的地址必须为绝对地址
protoc -I ../../protos --grpc_out=. --plugin=protoc-gen-grpc=`which grpc_cpp_plugin` ../../protos/route_guide.proto

protoc -I ../../protos --cpp_out=. ../../protos/route_guide.proto

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/*
 *
 * 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.
 *
 */

#include <algorithm>
#include <chrono>
#include <cmath>
#include <iostream>
#include <memory>
#include <string>

#include "helper.h"

#include <grpc/grpc.h>
#include <grpcpp/security/server_credentials.h>
#include <grpcpp/server.h>
#include <grpcpp/server_builder.h>
#include <grpcpp/server_context.h>
#ifdef BAZEL_BUILD
#include "examples/protos/route_guide.grpc.pb.h"
#else
#include "route_guide.grpc.pb.h"
#endif

using grpc::Server;
using grpc::ServerBuilder;
using grpc::ServerContext;
using grpc::ServerReader;
using grpc::ServerReaderWriter;
using grpc::ServerWriter;
using grpc::Status;
using routeguide::Feature;
using routeguide::Point;
using routeguide::Rectangle;
using routeguide::RouteGuide;
using routeguide::RouteNote;
using routeguide::RouteSummary;
using std::chrono::system_clock;

float ConvertToRadians(float num) { return num * 3.1415926 / 180; }

// The formula is based on http://mathforum.org/library/drmath/view/51879.html
float GetDistance(const Point& start, const Point& end) {
  const float kCoordFactor = 10000000.0;
  float lat_1 = start.latitude() / kCoordFactor;
  float lat_2 = end.latitude() / kCoordFactor;
  float lon_1 = start.longitude() / kCoordFactor;
  float lon_2 = end.longitude() / kCoordFactor;
  float lat_rad_1 = ConvertToRadians(lat_1);
  float lat_rad_2 = ConvertToRadians(lat_2);
  float delta_lat_rad = ConvertToRadians(lat_2 - lat_1);
  float delta_lon_rad = ConvertToRadians(lon_2 - lon_1);

  float a = pow(sin(delta_lat_rad / 2), 2) +
            cos(lat_rad_1) * cos(lat_rad_2) * pow(sin(delta_lon_rad / 2), 2);
  float c = 2 * atan2(sqrt(a), sqrt(1 - a));
  int R = 6371000;  // metres

  return R * c;
}

std::string GetFeatureName(const Point& point,
                           const std::vector<Feature>& feature_list) {
  for (const Feature& f : feature_list) {
    if (f.location().latitude() == point.latitude() &&
        f.location().longitude() == point.longitude()) {
      return f.name();
    }
  }
  return "";
}

class RouteGuideImpl final : public RouteGuide::Service {
 public:
  explicit RouteGuideImpl(const std::string& db) {
    routeguide::ParseDb(db, &feature_list_);
  }

  Status GetFeature(ServerContext* context, const Point* point,
                    Feature* feature) override {
    feature->set_name(GetFeatureName(*point, feature_list_));
    feature->mutable_location()->CopyFrom(*point);
    return Status::OK;
  }

  Status ListFeatures(ServerContext* context,
                      const routeguide::Rectangle* rectangle,
                      ServerWriter<Feature>* writer) override {
    auto lo = rectangle->lo();
    auto hi = rectangle->hi();
    long left = (std::min)(lo.longitude(), hi.longitude());
    long right = (std::max)(lo.longitude(), hi.longitude());
    long top = (std::max)(lo.latitude(), hi.latitude());
    long bottom = (std::min)(lo.latitude(), hi.latitude());
    for (const Feature& f : feature_list_) {
      if (f.location().longitude() >= left &&
          f.location().longitude() <= right &&
          f.location().latitude() >= bottom && f.location().latitude() <= top) {
        writer->Write(f);
      }
    }
    return Status::OK;
  }

  Status RecordRoute(ServerContext* context, ServerReader<Point>* reader,
                     RouteSummary* summary) override {
    Point point;
    int point_count = 0;
    int feature_count = 0;
    float distance = 0.0;
    Point previous;

    system_clock::time_point start_time = system_clock::now();
    while (reader->Read(&point)) {
      point_count++;
      if (!GetFeatureName(point, feature_list_).empty()) {
        feature_count++;
      }
      if (point_count != 1) {
        distance += GetDistance(previous, point);
      }
      previous = point;
    }
    system_clock::time_point end_time = system_clock::now();
    summary->set_point_count(point_count);
    summary->set_feature_count(feature_count);
    summary->set_distance(static_cast<long>(distance));
    auto secs =
        std::chrono::duration_cast<std::chrono::seconds>(end_time - start_time);
    summary->set_elapsed_time(secs.count());

    return Status::OK;
  }

  Status RouteChat(ServerContext* context,
                   ServerReaderWriter<RouteNote, RouteNote>* stream) override {
    RouteNote note;
    while (stream->Read(&note)) {
      std::unique_lock<std::mutex> lock(mu_);
      for (const RouteNote& n : received_notes_) {
        if (n.location().latitude() == note.location().latitude() &&
            n.location().longitude() == note.location().longitude()) {
          stream->Write(n);
        }
      }
      received_notes_.push_back(note);
    }

    return Status::OK;
  }

 private:
  std::vector<Feature> feature_list_;
  std::mutex mu_;
  std::vector<RouteNote> received_notes_;
};

void RunServer(const std::string& db_path) {
  std::string server_address("0.0.0.0:50051");
  RouteGuideImpl service(db_path);

  ServerBuilder builder;
  builder.AddListeningPort(server_address, grpc::InsecureServerCredentials());
  builder.RegisterService(&service);
  std::unique_ptr<Server> server(builder.BuildAndStart());
  std::cout << "Server listening on " << server_address << std::endl;
  server->Wait();
}

int main(int argc, char** argv) {
  // Expect only arg: --db_path=path/to/route_guide_db.json.
  std::string db = routeguide::GetDbFileContent(argc, argv);
  RunServer(db);

  return 0;
}

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#include <chrono>
#include <iostream>
#include <memory>
#include <random>
#include <string>
#include <thread>

#include "helper.h"

#include <grpc/grpc.h>
#include <grpcpp/channel.h>
#include <grpcpp/client_context.h>
#include <grpcpp/create_channel.h>
#include <grpcpp/security/credentials.h>
#ifdef BAZEL_BUILD
#include "examples/protos/route_guide.grpc.pb.h"
#else
#include "route_guide.grpc.pb.h"
#endif

using grpc::Channel;
using grpc::ClientContext;
using grpc::ClientReader;
using grpc::ClientReaderWriter;
using grpc::ClientWriter;
using grpc::Status;
using routeguide::Feature;
using routeguide::Point;
using routeguide::Rectangle;
using routeguide::RouteGuide;
using routeguide::RouteNote;
using routeguide::RouteSummary;

Point MakePoint(long latitude, long longitude) {
  Point p;
  p.set_latitude(latitude);
  p.set_longitude(longitude);
  return p;
}

Feature MakeFeature(const std::string& name, long latitude, long longitude) {
  Feature f;
  f.set_name(name);
  f.mutable_location()->CopyFrom(MakePoint(latitude, longitude));
  return f;
}

RouteNote MakeRouteNote(const std::string& message, long latitude,
                        long longitude) {
  RouteNote n;
  n.set_message(message);
  n.mutable_location()->CopyFrom(MakePoint(latitude, longitude));
  return n;
}

class RouteGuideClient {
 public:
  RouteGuideClient(std::shared_ptr<Channel> channel, const std::string& db)
      : stub_(RouteGuide::NewStub(channel)) {
    routeguide::ParseDb(db, &feature_list_);
  }

  void GetFeature() {
    Point point;
    Feature feature;
    point = MakePoint(409146138, -746188906);
    GetOneFeature(point, &feature);
    point = MakePoint(0, 0);
    GetOneFeature(point, &feature);
  }

  void ListFeatures() {
    routeguide::Rectangle rect;
    Feature feature;
    ClientContext context;

    rect.mutable_lo()->set_latitude(400000000);
    rect.mutable_lo()->set_longitude(-750000000);
    rect.mutable_hi()->set_latitude(420000000);
    rect.mutable_hi()->set_longitude(-730000000);
    std::cout << "Looking for features between 40, -75 and 42, -73"
              << std::endl;

    std::unique_ptr<ClientReader<Feature> > reader(
        stub_->ListFeatures(&context, rect));
    while (reader->Read(&feature)) {
      std::cout << "Found feature called " << feature.name() << " at "
                << feature.location().latitude() / kCoordFactor_ << ", "
                << feature.location().longitude() / kCoordFactor_ << std::endl;
    }
    Status status = reader->Finish();
    if (status.ok()) {
      std::cout << "ListFeatures rpc succeeded." << std::endl;
    } else {
      std::cout << "ListFeatures rpc failed." << std::endl;
    }
  }

  void RecordRoute() {
    Point point;
    RouteSummary stats;
    ClientContext context;
    const int kPoints = 10;
    unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();

    std::default_random_engine generator(seed);
    std::uniform_int_distribution<int> feature_distribution(
        0, feature_list_.size() - 1);
    std::uniform_int_distribution<int> delay_distribution(500, 1500);

    std::unique_ptr<ClientWriter<Point> > writer(
        stub_->RecordRoute(&context, &stats));
    for (int i = 0; i < kPoints; i++) {
      const Feature& f = feature_list_[feature_distribution(generator)];
      std::cout << "Visiting point " << f.location().latitude() / kCoordFactor_
                << ", " << f.location().longitude() / kCoordFactor_
                << std::endl;
      if (!writer->Write(f.location())) {
        // Broken stream.
        break;
      }
      std::this_thread::sleep_for(
          std::chrono::milliseconds(delay_distribution(generator)));
    }
    writer->WritesDone();
    Status status = writer->Finish();
    if (status.ok()) {
      std::cout << "Finished trip with " << stats.point_count() << " points\n"
                << "Passed " << stats.feature_count() << " features\n"
                << "Travelled " << stats.distance() << " meters\n"
                << "It took " << stats.elapsed_time() << " seconds"
                << std::endl;
    } else {
      std::cout << "RecordRoute rpc failed." << std::endl;
    }
  }

  void RouteChat() {
    ClientContext context;

    std::shared_ptr<ClientReaderWriter<RouteNote, RouteNote> > stream(
        stub_->RouteChat(&context));

    std::thread writer([stream]() {
      std::vector<RouteNote> notes{MakeRouteNote("First message", 0, 0),
                                   MakeRouteNote("Second message", 0, 1),
                                   MakeRouteNote("Third message", 1, 0),
                                   MakeRouteNote("Fourth message", 0, 0)};
      for (const RouteNote& note : notes) {
        std::cout << "Sending message " << note.message() << " at "
                  << note.location().latitude() << ", "
                  << note.location().longitude() << std::endl;
        stream->Write(note);
      }
      stream->WritesDone();
    });

    RouteNote server_note;
    while (stream->Read(&server_note)) {
      std::cout << "Got message " << server_note.message() << " at "
                << server_note.location().latitude() << ", "
                << server_note.location().longitude() << std::endl;
    }
    writer.join();
    Status status = stream->Finish();
    if (!status.ok()) {
      std::cout << "RouteChat rpc failed." << std::endl;
    }
  }

 private:
  bool GetOneFeature(const Point& point, Feature* feature) {
    ClientContext context;
    Status status = stub_->GetFeature(&context, point, feature);
    if (!status.ok()) {
      std::cout << "GetFeature rpc failed." << std::endl;
      return false;
    }
    if (!feature->has_location()) {
      std::cout << "Server returns incomplete feature." << std::endl;
      return false;
    }
    if (feature->name().empty()) {
      std::cout << "Found no feature at "
                << feature->location().latitude() / kCoordFactor_ << ", "
                << feature->location().longitude() / kCoordFactor_ << std::endl;
    } else {
      std::cout << "Found feature called " << feature->name() << " at "
                << feature->location().latitude() / kCoordFactor_ << ", "
                << feature->location().longitude() / kCoordFactor_ << std::endl;
    }
    return true;
  }

  const float kCoordFactor_ = 10000000.0;
  std::unique_ptr<RouteGuide::Stub> stub_;
  std::vector<Feature> feature_list_;
};

int main(int argc, char** argv) {
  // Expect only arg: --db_path=path/to/route_guide_db.json.
  std::string db = routeguide::GetDbFileContent(argc, argv);
  RouteGuideClient guide(
      grpc::CreateChannel("localhost:50051",
                          grpc::InsecureChannelCredentials()),
      db);

  std::cout << "-------------- GetFeature --------------" << std::endl;
  guide.GetFeature();
  std::cout << "-------------- ListFeatures --------------" << std::endl;
  guide.ListFeatures();
  std::cout << "-------------- RecordRoute --------------" << std::endl;
  guide.RecordRoute();
  std::cout << "-------------- RouteChat --------------" << std::endl;
  guide.RouteChat();

  return 0;
}

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message DemandSummary
{
    required uint32 solutionIndex     = 1;
    required uint32 demandID          = 2;
}
message ComputeResponse
{
    repeated DemandSummary solutionInfo  = 3;
}

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ComputeResponse response;

for ( int i = 0; i < demList.size(); ++i ) {

    DemandSummary* summary = response.add_solutioninfo();
    summary->set_solutionindex(solutionID);
    summary->set_demandid(demList[i].toUInt());
}

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int main(int argc, char* argv[])
{

    GOOGLE_PROTOBUF_VERIFY_VERSION;

    Family family;
    Person* person;

    // 添加一个家庭成员，John
    person = family.add_person();
    person->set_age(25);
    person->set_name("John");

    // 添加一个家庭成员，Lucy
    person = family.add_person();
    person->set_age(23);
    person->set_name("Lucy");

    // 添加一个家庭成员，Tony
    person = family.add_person();
    person->set_age(2);
    person->set_name("Tony");

    // 显示所有家庭成员
    int size = family.person_size();

    cout << "这个家庭有 " << size << " 个成员，如下：" << endl;

    for(int i=0; i<size; i++)
    {
        Person psn = family.person(i);
        cout << i+1 << ". " << psn.name() << ", 年龄 " << psn.age() << endl;
    }
    return 0;
}

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#include <iostream>
#include <memory>
#include <string>

#include <grpcpp/ext/proto_server_reflection_plugin.h>
#include <grpcpp/grpcpp.h>
#include <grpcpp/health_check_service_interface.h>

#include "helloworld.grpc.pb.h"
#include <thread>
#include <unistd.h>

using grpc::CallbackServerContext;
using grpc::Server;
using grpc::ServerBuilder;
using grpc::ServerUnaryReactor;
using grpc::Status;
using helloworld::Greeter;
using helloworld::HelloReply;
using helloworld::HelloRequest;

std::unique_ptr<Server> server;
std::thread s;
void shutdown(){
    sleep(4);
    server->Shutdown();
}
// Logic and data behind the server's behavior.
class GreeterServiceImpl final : public Greeter::CallbackService {
  ServerUnaryReactor* SayHello(CallbackServerContext* context,
                               const HelloRequest* request,
                               HelloReply* reply) override {
    std::string prefix("Hello ");
    reply->set_message(prefix + request->name());

    ServerUnaryReactor* reactor = context->DefaultReactor();
    reactor->Finish(Status::OK);

    s = std::thread([&](){
        sleep(4);
        server->Shutdown();

    });
    return reactor;
  }
};

void RunServer() {
  std::string server_address("0.0.0.0:50051");
  GreeterServiceImpl service;

  grpc::EnableDefaultHealthCheckService(true);
  grpc::reflection::InitProtoReflectionServerBuilderPlugin();
  ServerBuilder builder;
  // Listen on the given address without any authentication mechanism.
  builder.AddListeningPort(server_address, grpc::InsecureServerCredentials());
  // Register "service" as the instance through which we'll communicate with
  // clients. In this case it corresponds to an *synchronous* service.
  builder.RegisterService(&service);
  // Finally assemble the server.
  //std::unique_ptr<Server> server(builder.BuildAndStart());
  server =std::move(builder.BuildAndStart());
  std::cout << "Server listening on " << server_address << std::endl;

  // Wait for the server to shutdown. Note that some other thread must be
  // responsible for shutting down the server for this call to ever return.
  server->Wait();
}

int main(int argc, char** argv) {
  RunServer();
  s.join();
  std::cout << "RPC server is shutdonw and continue to run" << std::endl;
  return 0;
}

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#include <condition_variable>
#include <iostream>
#include <memory>
#include <mutex>
#include <string>

#include <grpcpp/grpcpp.h>

#include "helloworld.grpc.pb.h"

using grpc::Channel;
using grpc::ClientContext;
using grpc::Status;
using helloworld::Greeter;
using helloworld::HelloReply;
using helloworld::HelloRequest;

class GreeterClient {
 public:
  GreeterClient(std::shared_ptr<Channel> channel)
      : stub_(Greeter::NewStub(channel)) {}

  // Assembles the client's payload, sends it and presents the response back
  // from the server.
  std::string SayHello(const std::string& user) {
    // Data we are sending to the server.
    HelloRequest request;
    request.set_name(user);

    // Container for the data we expect from the server.
    HelloReply reply;

    // Context for the client. It could be used to convey extra information to
    // the server and/or tweak certain RPC behaviors.
    ClientContext context;

    // The actual RPC.
    std::mutex mu;
    std::condition_variable cv;
    bool done = false;
    Status status;
    stub_->async()->SayHello(&context, &request, &reply,
                             [&mu, &cv, &done, &status](Status s) {
                               status = std::move(s);
                               std::lock_guard<std::mutex> lock(mu);
                               done = true;
                               cv.notify_one();
                             });

    std::unique_lock<std::mutex> lock(mu);
    while (!done) {
      cv.wait(lock);
    }

    // Act upon its status.
    if (status.ok()) {
      return reply.message();
    } else {
      std::cout << status.error_code() << ": " << status.error_message()
                << std::endl;
      return "RPC failed";
    }
  }

 private:
  std::unique_ptr<Greeter::Stub> stub_;
};

int main(int argc, char** argv) {
  // Instantiate the client. It requires a channel, out of which the actual RPCs
  // are created. This channel models a connection to an endpoint specified by
  // the argument "--target=" which is the only expected argument.
  // We indicate that the channel isn't authenticated (use of
  // InsecureChannelCredentials()).
  std::string target_str;
  std::string arg_str("--target");
  if (argc > 1) {
    std::string arg_val = argv[1];
    size_t start_pos = arg_val.find(arg_str);
    if (start_pos != std::string::npos) {
      start_pos += arg_str.size();
      if (arg_val[start_pos] == '=') {
        target_str = arg_val.substr(start_pos + 1);
      } else {
        std::cout << "The only correct argument syntax is --target="
                  << std::endl;
        return 0;
      }
    } else {
      std::cout << "The only acceptable argument is --target=" << std::endl;
      return 0;
    }
  } else {
    target_str = "localhost:50051";
  }
  GreeterClient greeter(
      grpc::CreateChannel(target_str, grpc::InsecureChannelCredentials()));
  std::string user("world");
  std::string reply = greeter.SayHello(user);
  std::cout << "Greeter received: " << reply << std::endl;

  return 0;
}

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class Stub final : public StubInterface {
public:
  Stub(const std::shared_ptr< ::grpc::ChannelInterface>& channel, const ::grpc::StubOptions& options = ::grpc::StubOptions());
  ::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 async final :
    public StubInterface::async_interface {
  public:
    void SayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response, std::function<void(::grpc::Status)>) override;
    void SayHello(::grpc::ClientContext* context, const ::helloworld::HelloRequest* request, ::helloworld::HelloReply* response, ::grpc::ClientUnaryReactor* reactor) override;
  private:
    friend class Stub;
    explicit async(Stub* stub): stub_(stub) { }
    Stub* stub() { return stub_; }
    Stub* stub_;
  };
  class async* async() override { return &async_stub_; }

private:
  std::shared_ptr< ::grpc::ChannelInterface> channel_;
  class 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());

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from concurrent import futures
import logging

import grpc
import helloworld_pb2
import helloworld_pb2_grpc

server = None
class Greeter(helloworld_pb2_grpc.GreeterServicer):

    def SayHello(self, request, context):
        server.stop(2)    # stop in 2 seconds
        return helloworld_pb2.HelloReply(message='Hello, %s!' % request.name)


def serve():
    global server
    server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
    helloworld_pb2_grpc.add_GreeterServicer_to_server(Greeter(), server)
    server.add_insecure_port('[::]:50051')
    server.start()
    server.wait_for_termination()


if __name__ == '__main__':
    logging.basicConfig()
    serve()