Rework DB session + transactions. Now can handle multiple read only transactions in parallel

src/database/Session.hpp

@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2013 Emeric Poupon
+ *
+ * This file is part of LMS.
+ *
+ * LMS is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LMS is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with LMS.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <shared_mutex>
+#include <mutex>
+#include <boost/filesystem.hpp>
+#include <memory>
+
+#include <Wt/Dbo/Dbo.h>
+#include <Wt/Dbo/SqlConnectionPool.h>
+#include <Wt/Auth/Dbo/AuthInfo.h>
+
+#include <Wt/Auth/Dbo/UserDatabase.h>
+#include <Wt/Auth/Login.h>
+#include <Wt/Auth/PasswordService.h>
+
+#include "User.hpp"
+
+namespace Database {
+
+using AuthInfo = Wt::Auth::Dbo::AuthInfo<User>;
+using UserDatabase = Wt::Auth::Dbo::UserDatabase<AuthInfo>;
+
+class UniqueTransaction
+{
+	public:
+		~UniqueTransaction();
+
+	private:
+		friend class Session;
+		UniqueTransaction(std::shared_timed_mutex& mutex, Wt::Dbo::Session& session);
+
+		std::unique_lock<std::shared_timed_mutex> _lock;
+		Wt::Dbo::Transaction _transaction;
+};
+
+class SharedTransaction
+{
+	public:
+		~SharedTransaction();
+
+	private:
+		friend class Session;
+		SharedTransaction(std::shared_timed_mutex& mutex, Wt::Dbo::Session& session);
+
+		std::shared_lock<std::shared_timed_mutex> _lock;
+		Wt::Dbo::Transaction _transaction;
+};
+
+class Session
+{
+	public:
+		Session(const Session&) = delete;
+		Session(Session&&) = delete;
+		Session& operator=(const Session&) = delete;
+		Session& operator=(Session&&) = delete;
+
+		std::unique_ptr<UniqueTransaction> createUniqueTransaction();
+		std::unique_ptr<SharedTransaction> createSharedTransaction();
+
+		void checkUniqueLocked();
+		void checkSharedLocked();
+
+		void optimize();
+
+		// User management
+		Wt::Dbo::ptr<User>	getLoggedUser();	// get the current user, may return empty
+		Wt::Dbo::ptr<User>	getUser(const std::string& loginName);
+		std::string		getUserLoginName(Wt::Dbo::ptr<User> user);
+		Wt::Dbo::ptr<User>	createUser(const std::string& loginName, const std::string& password);
+		void			removeUser(Wt::Dbo::ptr<User> user);
+		bool			checkUserPassword(const std::string& loginName, const std::string& password);
+		void			updateUserPassword(Wt::Dbo::ptr<User> user, const std::string& password);
+		Wt::WDateTime		getUserLastLoginAttempt(Wt::Dbo::ptr<User> user);
+
+		Wt::Auth::AbstractUserDatabase& getUserDatabase();
+		Wt::Auth::Login& getLogin() { return _login; } // TODO move
+
+		// Long living shared associated services
+		static void configureAuth();
+		static const Wt::Auth::AuthService& getAuthService();
+		static const Wt::Auth::PasswordService& getPasswordService();
+
+		Wt::Dbo::Session& getDboSession() { return _session; }
+
+	private:
+		friend class Database;
+
+		Session(std::shared_timed_mutex& mutex, Wt::Dbo::SqlConnectionPool& connectionPool);
+
+		void doDatabaseMigrationIfNeeded();
+		void prepareTables(); // need to run only once at startup
+
+		 Wt::Dbo::ptr<User> getUser(const Wt::Auth::User& authUser);
+
+		std::shared_timed_mutex&	_mutex;
+		Wt::Dbo::Session		_session;
+		std::unique_ptr<UserDatabase>	_users;
+		Wt::Auth::Login 		_login;
+
+};
+
+} // namespace Database
+
+