sample/using_external_io_context/main.cpp

#include <iostream>

#include <restinio/all.hpp>

// Create request handler.
auto create_request_handler( std::string tag )
{
    return [tag]( auto req ) {
            if( restinio::http_method_get() == req->header().method() &&
                req->header().request_target() == "/" )
            {
                req->create_response()
                    .append_header( restinio::http_field::server, "RESTinio hello world server" )
                    .append_header_date_field()
                    .append_header( restinio::http_field::content_type, "text/plain; charset=utf-8" )
                    .set_body( "Server tag: " + tag )
                    .done();

                return restinio::request_accepted();
            }

            return restinio::request_rejected();
        };
}

int main()
{
    // Since RESTinio supports both stand-alone ASIO and boost::ASIO
    // we specify an alias for a concrete asio namesace.
    // That's makes it possible to compile the code in both cases.
    // Typicaly only one of ASIO variants would be used,
    // and so only asio::* or only boost::asio::* would be applied.
    namespace asio_ns = restinio::asio_ns;

    try
    {
        // External io_context.
        asio_ns::io_context io_context;

        using server_t = restinio::http_server_t<>;
        using settings_t = restinio::server_settings_t<>;

        server_t srv1{
            restinio::external_io_context( io_context ),
            settings_t{}
                .port( 8080 )
                .address( "localhost" )
                .request_handler( create_request_handler( "server1" ) ) };

        server_t srv2{
            restinio::external_io_context( io_context ),
            settings_t{}
                .port( 8081 )
                .address( "localhost" )
                .request_handler( create_request_handler( "server2" ) ) };

        asio_ns::signal_set break_signals{ io_context, SIGINT };
        break_signals.async_wait(
            [&]( const asio_ns::error_code & ec, int ){
                if( !ec )
                {
                    srv1.close_sync();
                    srv2.close_sync();
                }
            } );

        asio_ns::post( io_context, [&]{
            srv1.open_sync();
            srv2.open_sync();
        } );

        io_context.run();
    }
    catch( const std::exception & ex )
    {
        std::cerr << "Error: " << ex.what() << std::endl;
        return 1;
    }

    return 0;
}