<?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\Connection;
use Predis\Command\CommandInterface;
use Predis\CommunicationException;
use Predis\Protocol\ProtocolException;
/**
* Base class with the common logic used by connection classes to communicate
* with Redis.
*
* @author Daniele Alessandri <suppakilla@gmail.com>
*/
abstract class AbstractConnection implements NodeConnectionInterface
{
private $resource;
private $cachedId;
protected $parameters;
protected $initCommands = array();
/**
* @param ParametersInterface $parameters Initialization parameters for the connection.
*/
public function __construct(ParametersInterface $parameters)
{
$this->parameters = $this->assertParameters($parameters);
}
/**
* Disconnects from the server and destroys the underlying resource when
* PHP's garbage collector kicks in.
*/
public function __destruct()
{
$this->disconnect();
}
/**
* Checks some of the parameters used to initialize the connection.
*
* @param ParametersInterface $parameters Initialization parameters for the connection.
*
* @throws \InvalidArgumentException
*
* @return ParametersInterface
*/
protected function assertParameters(ParametersInterface $parameters)
{
switch ($parameters->scheme) {
case 'tcp':
case 'redis':
case 'unix':
break;
default:
throw new \InvalidArgumentException("Invalid scheme: '$parameters->scheme'.");
}
return $parameters;
}
/**
* Creates the underlying resource used to communicate with Redis.
*
* @return mixed
*/
abstract protected function createResource();
/**
* {@inheritdoc}
*/
public function isConnected()
{
return isset($this->resource);
}
/**
* {@inheritdoc}
*/
public function connect()
{
if (!$this->isConnected()) {
$this->resource = $this->createResource();
return true;
}
return false;
}
/**
* {@inheritdoc}
*/
public function disconnect()
{
unset($this->resource);
}
/**
* {@inheritdoc}
*/
public function addConnectCommand(CommandInterface $command)
{
$this->initCommands[] = $command;
}
/**
* {@inheritdoc}
*/
public function executeCommand(CommandInterface $command)
{
$this->writeRequest($command);
return $this->readResponse($command);
}
/**
* {@inheritdoc}
*/
public function readResponse(CommandInterface $command)
{
return $this->read();
}
/**
* Helper method that returns an exception message augmented with useful
* details from the connection parameters.
*
* @param string $message Error message.
*
* @return string
*/
private function createExceptionMessage($message)
{
$parameters = $this->parameters;
if ($parameters->scheme === 'unix') {
return "$message [$parameters->scheme:$parameters->path]";
}
if (filter_var($parameters->host, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
return "$message [$parameters->scheme://[$parameters->host]:$parameters->port]";
}
return "$message [$parameters->scheme://$parameters->host:$parameters->port]";
}
/**
* Helper method to handle connection errors.
*
* @param string $message Error message.
* @param int $code Error code.
*/
protected function onConnectionError($message, $code = null)
{
CommunicationException::handle(
new ConnectionException($this, static::createExceptionMessage($message), $code)
);
}
/**
* Helper method to handle protocol errors.
*
* @param string $message Error message.
*/
protected function onProtocolError($message)
{
CommunicationException::handle(
new ProtocolException($this, static::createExceptionMessage($message))
);
}
/**
* {@inheritdoc}
*/
public function getResource()
{
if (isset($this->resource)) {
return $this->resource;
}
$this->connect();
return $this->resource;
}
/**
* {@inheritdoc}
*/
public function getParameters()
{
return $this->parameters;
}
/**
* Gets an identifier for the connection.
*
* @return string
*/
protected function getIdentifier()
{
if ($this->parameters->scheme === 'unix') {
return $this->parameters->path;
}
return "{$this->parameters->host}:{$this->parameters->port}";
}
/**
* {@inheritdoc}
*/
public function __toString()
{
if (!isset($this->cachedId)) {
$this->cachedId = $this->getIdentifier();
}
return $this->cachedId;
}
/**
* {@inheritdoc}
*/
public function __sleep()
{
return array('parameters', 'initCommands');
}
}
