// // Copyright (c) 2019-2022 Ruben Perez Hidalgo (rubenperez038 at gmail dot com) // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // //[example_unix_socket #include #include #include #include #include void print_employee(boost::mysql::row_view employee) { std::cout << "Employee '" << employee[0] << " " // first_name (string) << employee[1] << "' earns " // last_name (string) << employee[2] << " dollars yearly\n"; // salary (double) } #define ASSERT(expr) \ if (!(expr)) \ { \ std::cerr << "Assertion failed: " #expr << std::endl; \ exit(1); \ } /* UNIX sockets are only available in, er, UNIX systems. Typedefs for * UNIX socket-based connections are only available in UNIX systems. * Check for BOOST_ASIO_HAS_LOCAL_SOCKETS to know if UNIX socket * typedefs are available in your system. */ #ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS void main_impl(int argc, char** argv) { if (argc != 3 && argc != 4) { std::cerr << "Usage: " << argv[0] << " []\n"; exit(1); } const char* socket_path = "/var/run/mysqld/mysqld.sock"; if (argc == 4) { socket_path = argv[3]; } /** * Connection parameters that tell us where and how to connect to the MySQL server. * There are two types of parameters: * - UNIX-level connection parameters, identifying the UNIX socket to connect to. * - MySQL level parameters: database credentials and schema to use. */ boost::asio::local::stream_protocol::endpoint ep(socket_path); boost::mysql::handshake_params params( argv[1], // username argv[2], // password "boost_mysql_examples" // database to use; leave empty or omit the parameter for no // database ); boost::asio::io_context ctx; boost::asio::ssl::context ssl_ctx(boost::asio::ssl::context::tls_client); // Connection to the MySQL server, over a UNIX socket boost::mysql::unix_ssl_connection conn(ctx, ssl_ctx); conn.connect(ep, params); // UNIX socket connect and MySQL handshake const char* sql = "SELECT first_name, last_name, salary FROM employee WHERE company_id = 'HGS'"; boost::mysql::unix_ssl_resultset result; conn.query(sql, result); // Get all the rows in the resultset boost::mysql::rows all_rows; result.read_all(all_rows); for (const auto& employee : all_rows) { print_employee(employee); } // We can issue any SQL statement, not only SELECTs. In this case, the returned // resultset will have no fields and no rows sql = "UPDATE employee SET salary = 10000 WHERE first_name = 'Underpaid'"; conn.query(sql, result); ASSERT(result.complete()); // UPDATE queries never return rows // Check we have updated our poor intern salary conn.query("SELECT salary FROM employee WHERE first_name = 'Underpaid'", result); result.read_all(all_rows); double salary = all_rows.at(0).at(0).as_double(); ASSERT(salary == 10000); // Notify the MySQL server we want to quit, then close the underlying connection. conn.close(); } #else void main_impl(int, char**) { std::cout << "Sorry, your system does not support UNIX sockets" << std::endl; } #endif int main(int argc, char** argv) { try { main_impl(argc, argv); } catch (const boost::system::system_error& err) { std::cerr << "Error: " << err.what() << ", error code: " << err.code() << std::endl; return 1; } catch (const std::exception& err) { std::cerr << "Error: " << err.what() << std::endl; return 1; } } //]