cpp20_protobuf.cpp

/* Copyright (c) 2018-2022 Marcelo Zimbres Silva (mzimbres@gmail.com)
 *
 * Distributed under the Boost Software License, Version 1.0. (See
 * accompanying file LICENSE.txt)
 */
 
#include <boost/redis/connection.hpp>
#include <boost/redis/resp3/serialization.hpp>
#include <boost/asio/deferred.hpp>
#include <boost/asio/co_spawn.hpp>
#include <boost/asio/detached.hpp>
#include <boost/asio/consign.hpp>
#include <boost/system/errc.hpp>
#include <iostream>
 
// See the definition in person.proto. This header is automatically
// generated by CMakeLists.txt.
#include "person.pb.h"
 
#if defined(BOOST_ASIO_HAS_CO_AWAIT)
 
namespace asio = boost::asio;
using boost::redis::request;
using boost::redis::response;
using boost::redis::operation;
using boost::redis::ignore_t;
using boost::redis::config;
using boost::redis::connection;
 
// The protobuf type described in example/person.proto
using tutorial::person;
 
// Boost.Redis customization points (example/protobuf.hpp)
namespace tutorial
{
 
// Below I am using a Boost.Redis to indicate a protobuf error, this
// is ok for an example, users however might want to define their own
// error codes.
void boost_redis_to_bulk(std::string& to, person const& u)
{
   std::string tmp;
   if (!u.SerializeToString(&tmp))
      throw boost::system::system_error(boost::redis::error::invalid_data_type);
 
   boost::redis::resp3::boost_redis_to_bulk(to, tmp);
}
 
void boost_redis_from_bulk(person& u, std::string_view sv, boost::system::error_code& ec)
{
   std::string const tmp {sv};
   if (!u.ParseFromString(tmp))
      ec = boost::redis::error::invalid_data_type;
}
 
} // tutorial
 
using tutorial::boost_redis_to_bulk;
using tutorial::boost_redis_from_bulk;
 
asio::awaitable<void> co_main(config cfg)
{
   auto ex = co_await asio::this_coro::executor;
   auto conn = std::make_shared<connection>(ex);
   conn->async_run(cfg, {}, asio::consign(asio::detached, conn));
 
   person p;
   p.set_name("Louis");
   p.set_id(3);
   p.set_email("No email yet.");
 
   request req;
   req.push("SET", "protobuf-key", p);
   req.push("GET", "protobuf-key");
 
   response<ignore_t, person> resp;
 
   // Sends the request and receives the response.
   co_await conn->async_exec(req, resp, asio::deferred);
   conn->cancel();
 
   std::cout
      << "Name: " << std::get<1>(resp).value().name() << "\n"
      << "Age: " << std::get<1>(resp).value().id() << "\n"
      << "Email: " << std::get<1>(resp).value().email() << "\n";
}
 
#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)