host/commands/echo_server/main.cpp

/*
 *
 * Copyright 2015 gRPC authors.
 * Copyright (C) 2023 The Android Open Source Project
 *
 * 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 <iostream>
#include <memory>
#include <string>

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

#include "echo.grpc.pb.h"

using echoserver::EchoReply;
using echoserver::EchoRequest;
using echoserver::EchoService;
using grpc::Server;
using grpc::ServerBuilder;
using grpc::ServerContext;
using grpc::Status;

DEFINE_string(grpc_uds_path, "", "grpc_uds_path");

class EchoServiceImpl final : public EchoService::Service {
  Status Echo(ServerContext* context, const EchoRequest* request,
              EchoReply* reply) override {
    reply->set_message(request->message());
    return Status::OK;
  }
};

void RunServer() {
  std::string server_address("unix:" + FLAGS_grpc_uds_path);
  EchoServiceImpl 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());
  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) {
  ::gflags::ParseCommandLineFlags(&argc, &argv, true);
  RunServer();

  return 0;
}