<?php
/*
* This file is part of SwiftMailer.
* (c) 2004-2009 Chris Corbyn
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
/**
* Throttles the rate at which emails are sent.
*
* @author Chris Corbyn
*/
class Swift_Plugins_ThrottlerPlugin extends Swift_Plugins_BandwidthMonitorPlugin implements Swift_Plugins_Sleeper, Swift_Plugins_Timer
{
/** Flag for throttling in bytes per minute */
const BYTES_PER_MINUTE = 0x01;
/** Flag for throttling in emails per second (Amazon SES) */
const MESSAGES_PER_SECOND = 0x11;
/** Flag for throttling in emails per minute */
const MESSAGES_PER_MINUTE = 0x10;
/**
* The Sleeper instance for sleeping.
*
* @var Swift_Plugins_Sleeper
*/
private $_sleeper;
/**
* The Timer instance which provides the timestamp.
*
* @var Swift_Plugins_Timer
*/
private $_timer;
/**
* The time at which the first email was sent.
*
* @var int
*/
private $_start;
/**
* The rate at which messages should be sent.
*
* @var int
*/
private $_rate;
/**
* The mode for throttling.
*
* This is {@link BYTES_PER_MINUTE} or {@link MESSAGES_PER_MINUTE}
*
* @var int
*/
private $_mode;
/**
* An internal counter of the number of messages sent.
*
* @var int
*/
private $_messages = 0;
/**
* Create a new ThrottlerPlugin.
*
* @param int $rate
* @param int $mode, defaults to {@link BYTES_PER_MINUTE}
* @param Swift_Plugins_Sleeper $sleeper (only needed in testing)
* @param Swift_Plugins_Timer $timer (only needed in testing)
*/
public function __construct($rate, $mode = self::BYTES_PER_MINUTE, Swift_Plugins_Sleeper $sleeper = null, Swift_Plugins_Timer $timer = null)
{
$this->_rate = $rate;
$this->_mode = $mode;
$this->_sleeper = $sleeper;
$this->_timer = $timer;
}
/**
* Invoked immediately before the Message is sent.
*
* @param Swift_Events_SendEvent $evt
*/
public function beforeSendPerformed(Swift_Events_SendEvent $evt)
{
$time = $this->getTimestamp();
if (!isset($this->_start)) {
$this->_start = $time;
}
$duration = $time - $this->_start;
switch ($this->_mode) {
case self::BYTES_PER_MINUTE:
$sleep = $this->_throttleBytesPerMinute($duration);
break;
case self::MESSAGES_PER_SECOND:
$sleep = $this->_throttleMessagesPerSecond($duration);
break;
case self::MESSAGES_PER_MINUTE:
$sleep = $this->_throttleMessagesPerMinute($duration);
break;
default:
$sleep = 0;
break;
}
if ($sleep > 0) {
$this->sleep($sleep);
}
}
/**
* Invoked when a Message is sent.
*
* @param Swift_Events_SendEvent $evt
*/
public function sendPerformed(Swift_Events_SendEvent $evt)
{
parent::sendPerformed($evt);
++$this->_messages;
}
/**
* Sleep for $seconds.
*
* @param int $seconds
*/
public function sleep($seconds)
{
if (isset($this->_sleeper)) {
$this->_sleeper->sleep($seconds);
} else {
sleep($seconds);
}
}
/**
* Get the current UNIX timestamp.
*
* @return int
*/
public function getTimestamp()
{
if (isset($this->_timer)) {
return $this->_timer->getTimestamp();
}
return time();
}
/**
* Get a number of seconds to sleep for.
*
* @param int $timePassed
*
* @return int
*/
private function _throttleBytesPerMinute($timePassed)
{
$expectedDuration = $this->getBytesOut() / ($this->_rate / 60);
return (int) ceil($expectedDuration - $timePassed);
}
/**
* Get a number of seconds to sleep for.
*
* @param int $timePassed
*
* @return int
*/
private function _throttleMessagesPerSecond($timePassed)
{
$expectedDuration = $this->_messages / ($this->_rate);
return (int) ceil($expectedDuration - $timePassed);
}
/**
* Get a number of seconds to sleep for.
*
* @param int $timePassed
*
* @return int
*/
private function _throttleMessagesPerMinute($timePassed)
{
$expectedDuration = $this->_messages / ($this->_rate / 60);
return (int) ceil($expectedDuration - $timePassed);
}
}