DaPortal
<?php //$Id$
//Copyright (c) 2016 Pierre Pronchery <khorben@defora.org>
//This file is part of DeforaOS Web DaPortal
//
//This program 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, version 3 of the License.
//
//This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
//DatabaseTransaction
class DatabaseTransaction implements Observable
{
//public
//properties
static public $STATUS_INITIAL = 0;
static public $STATUS_COMMIT_PENDING = 1;
static public $STATUS_ROLLBACK_PENDING = 2;
static public $STATUS_COMMIT = 3;
static public $STATUS_ROLLBACK = 4;
//methods
//essential
//DatabaseTransaction::DatabaseTransaction
public function __construct(Database $database)
{
$this->database = $database;
$this->observers = new \SplObjectStorage();
}
//DatabaseTransaction::~DatabaseTransaction
public function __destruct()
{
//XXX this will silently revert any transaction not completed
if($this->inTransaction())
$this->flush();
}
//accessors
//DatabaseTransaction::getStatus
public function getStatus()
{
if($this->count < 0)
return static::$STATUS_INITIAL;
if($this->count >= 1)
return $this->rollback
? static::$STATUS_ROLLBACK_PENDING
: static::$STATUS_COMMIT_PENDING;
return $this->rollback
? static::$STATUS_ROLLBACK
: static::$STATUS_COMMIT;
}
//DatabaseTransaction::inTransaction
public function inTransaction()
{
return $this->count > 0;
}
//Observable
//DatabaseTransaction::addObserver
public function addObserver(Observer $observer)
{
$this->observers->attach($observer);
}
//DatabaseTransaction::notifyObservers
public function notifyObservers()
{
//work on a copy in case Observers remove themselves
$observers = clone $this->observers;
foreach($observers as $observer)
$observer->notify($this);
}
//DatabaseTransaction::removeObserver
public function removeObserver(Observer $observer)
{
$this->observers->detach($observer);
}
//useful
//DatabaseTransaction::begin
public function begin()
{
if($this->inTransaction())
{
$this->count++;
return TRUE;
}
if($this->databaseBegin() === FALSE)
return FALSE;
$this->count = 1;
return TRUE;
}
//DatabaseTransaction::commit
public function commit()
{
if(!$this->inTransaction())
return FALSE;
if($this->count > 1)
{
$this->count--;
return TRUE;
}
return $this->complete();
}
//DatabaseTransaction::complete
public function complete()
{
if(!$this->inTransaction())
return FALSE;
$this->count = 0;
if($this->rollback)
$res = $this->databaseRollback();
else if(($res = $this->databaseCommit()) === FALSE)
$this->rollback = TRUE;
$this->notifyObservers();
$this->database->transactionComplete();
return $res;
}
//DatabaseTransaction::flush
public function flush()
{
$this->rollback = TRUE;
return $this->complete();
}
//DatabaseTransaction::rollback
public function rollback()
{
if(!$this->inTransaction())
return FALSE;
$this->rollback = TRUE;
if($this->count > 1)
{
$this->count--;
return TRUE;
}
return $this->complete();
}
//methods
//accessors
//DatabaseTransaction::getDatabase
protected function getDatabase()
{
return $this->database;
}
//useful
//DatabaseTransaction::databaseBegin
protected function databaseBegin()
{
return $this->database->query(NULL, 'START TRANSACTION');
}
//DatabaseTransaction::databaseCommit
protected function databaseCommit()
{
return $this->database->query(NULL, 'COMMIT');
}
//DatabaseTransaction::databaseRollback
protected function databaseRollback()
{
return $this->database->query(NULL, 'ROLLBACK');
}
//private
//properties
//Observable
private $observers;
private $database;
private $count = -1;
private $rollback = FALSE;
}
?>