Your IP : 3.144.21.237
<?php
/*
* This file is part of the Predis package.
*
* (c) Daniele Alessandri <suppakilla@gmail.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Predis\PubSub;
/**
* Base implementation of a PUB/SUB consumer abstraction based on PHP iterators.
*
* @author Daniele Alessandri <suppakilla@gmail.com>
*/
abstract class AbstractConsumer implements \Iterator
{
const SUBSCRIBE = 'subscribe';
const UNSUBSCRIBE = 'unsubscribe';
const PSUBSCRIBE = 'psubscribe';
const PUNSUBSCRIBE = 'punsubscribe';
const MESSAGE = 'message';
const PMESSAGE = 'pmessage';
const PONG = 'pong';
const STATUS_VALID = 1; // 0b0001
const STATUS_SUBSCRIBED = 2; // 0b0010
const STATUS_PSUBSCRIBED = 4; // 0b0100
private $position = null;
private $statusFlags = self::STATUS_VALID;
/**
* Automatically stops the consumer when the garbage collector kicks in.
*/
public function __destruct()
{
$this->stop(true);
}
/**
* Checks if the specified flag is valid based on the state of the consumer.
*
* @param int $value Flag.
*
* @return bool
*/
protected function isFlagSet($value)
{
return ($this->statusFlags & $value) === $value;
}
/**
* Subscribes to the specified channels.
*
* @param mixed $channel,... One or more channel names.
*/
public function subscribe($channel /*, ... */)
{
$this->writeRequest(self::SUBSCRIBE, func_get_args());
$this->statusFlags |= self::STATUS_SUBSCRIBED;
}
/**
* Unsubscribes from the specified channels.
*
* @param string ... One or more channel names.
*/
public function unsubscribe(/* ... */)
{
$this->writeRequest(self::UNSUBSCRIBE, func_get_args());
}
/**
* Subscribes to the specified channels using a pattern.
*
* @param mixed $pattern,... One or more channel name patterns.
*/
public function psubscribe($pattern /* ... */)
{
$this->writeRequest(self::PSUBSCRIBE, func_get_args());
$this->statusFlags |= self::STATUS_PSUBSCRIBED;
}
/**
* Unsubscribes from the specified channels using a pattern.
*
* @param string ... One or more channel name patterns.
*/
public function punsubscribe(/* ... */)
{
$this->writeRequest(self::PUNSUBSCRIBE, func_get_args());
}
/**
* PING the server with an optional payload that will be echoed as a
* PONG message in the pub/sub loop.
*
* @param string $payload Optional PING payload.
*/
public function ping($payload = null)
{
$this->writeRequest('PING', array($payload));
}
/**
* Closes the context by unsubscribing from all the subscribed channels. The
* context can be forcefully closed by dropping the underlying connection.
*
* @param bool $drop Indicates if the context should be closed by dropping the connection.
*
* @return bool Returns false when there are no pending messages.
*/
public function stop($drop = false)
{
if (!$this->valid()) {
return false;
}
if ($drop) {
$this->invalidate();
$this->disconnect();
} else {
if ($this->isFlagSet(self::STATUS_SUBSCRIBED)) {
$this->unsubscribe();
}
if ($this->isFlagSet(self::STATUS_PSUBSCRIBED)) {
$this->punsubscribe();
}
}
return !$drop;
}
/**
* Closes the underlying connection when forcing a disconnection.
*/
abstract protected function disconnect();
/**
* Writes a Redis command on the underlying connection.
*
* @param string $method Command ID.
* @param array $arguments Arguments for the command.
*/
abstract protected function writeRequest($method, $arguments);
/**
* {@inheritdoc}
*/
#[\ReturnTypeWillChange]
public function rewind()
{
// NOOP
}
/**
* Returns the last message payload retrieved from the server and generated
* by one of the active subscriptions.
*
* @return array
*/
#[\ReturnTypeWillChange]
public function current()
{
return $this->getValue();
}
/**
* {@inheritdoc}
*/
#[\ReturnTypeWillChange]
public function key()
{
return $this->position;
}
/**
* {@inheritdoc}
*/
#[\ReturnTypeWillChange]
public function next()
{
if ($this->valid()) {
++$this->position;
}
return $this->position;
}
/**
* Checks if the the consumer is still in a valid state to continue.
*
* @return bool
*/
#[\ReturnTypeWillChange]
public function valid()
{
$isValid = $this->isFlagSet(self::STATUS_VALID);
$subscriptionFlags = self::STATUS_SUBSCRIBED | self::STATUS_PSUBSCRIBED;
$hasSubscriptions = ($this->statusFlags & $subscriptionFlags) > 0;
return $isValid && $hasSubscriptions;
}
/**
* Resets the state of the consumer.
*/
protected function invalidate()
{
$this->statusFlags = 0; // 0b0000;
}
/**
* Waits for a new message from the server generated by one of the active
* subscriptions and returns it when available.
*
* @return array
*/
abstract protected function getValue();
}