void MainThreadWorker::onFinishShadowThread()
{
    emit workShadowThread(/* work params */)
}

std::string fullConfig;
std::condition_variable waiter;
auto configHandler = [&waiter](const std::string& configStr, bool)
{
    fullConfig = configStr;
    waiter.notify_all();
};

boost::asio::io_context ctx;
ConfigReaderWorker worker(ctx, settings, configHandler);
std::thread configThread = std::thread(std::bind([&ctx](){ctx.run();}));

std::mutex locker;
std::unique_lock lock(locker);
waiter.wait_for(lock, []{return !fullConfig.empty();});

worker.stop();
ctx.stop();

void ThreadWrapper::threadFunc()
{
    while (!done)
        doWork();
   emit workFinished();
}

if (!std::filesystem::exists(DbFile.toStdString()))
        std::ifstream file(DbFile.toStdString(), std::ios_base::in);

auto сonnection = QSqlDatabase::addDatabase("QSQLITE", "SomeDatabase");
connection.setDatabaseName(DbFile);
bool isOpened = connection.open();
    if (!isOpened)
        return;
connection.transaction();
for (auto& createSQL : CreateDB)
    connection.exec(createSQL);
connection.commit();