* @link http://www.yiiframework.com/
* @copyright 2008-2013 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
/**
* CRedisCache implements a cache application component based on {@link http://redis.io/ redis}.
*
* CRedisCache needs to be configured with {@link hostname}, {@link port} and {@link database} of the server
* to connect to. By default CRedisCache assumes there is a redis server running on localhost at
* port 6379 and uses the database number 0.
*
* CRedisCache also supports {@link http://redis.io/commands/auth the AUTH command} of redis.
* When the server needs authentication, you can set the {@link password} property to
* authenticate with the server after connect.
*
* See {@link CCache} manual for common cache operations that are supported by CRedisCache.
*
* To use CRedisCache as the cache application component, configure the application as follows,
*
* array(
* 'components'=>array(
* 'cache'=>array(
* 'class'=>'CRedisCache',
* 'hostname'=>'localhost',
* 'port'=>6379,
* 'database'=>0,
* ),
* ),
* )
*
*
* The minimum required redis version is 2.0.0.
*
* @author Carsten Brandt
* @package system.caching
* @since 1.1.14
*/
class CRedisCache extends CCache
{
/**
* @var string hostname to use for connecting to the redis server. Defaults to 'localhost'.
*/
public $hostname='localhost';
/**
* @var int the port to use for connecting to the redis server. Default port is 6379.
*/
public $port=6379;
/**
* @var string the password to use to authenticate with the redis server. If not set, no AUTH command will be sent.
*/
public $password;
/**
* @var int the redis database to use. This is an integer value starting from 0. Defaults to 0.
*/
public $database=0;
/**
* @var float timeout to use for connection to redis. If not set the timeout set in php.ini will be used: ini_get("default_socket_timeout")
*/
public $timeout=null;
/**
* @var resource redis socket connection
*/
private $_socket;
/**
* Establishes a connection to the redis server.
* It does nothing if the connection has already been established.
* @throws CException if connecting fails
*/
protected function connect()
{
$this->_socket=@stream_socket_client(
$this->hostname.':'.$this->port,
$errorNumber,
$errorDescription,
$this->timeout ? $this->timeout : ini_get("default_socket_timeout")
);
if ($this->_socket)
{
if($this->password!==null)
$this->executeCommand('AUTH',array($this->password));
$this->executeCommand('SELECT',array($this->database));
}
else
throw new CException('Failed to connect to redis: '.$errorDescription,(int)$errorNumber);
}
/**
* Executes a redis command.
* For a list of available commands and their parameters see {@link http://redis.io/commands}.
*
* @param string $name the name of the command
* @param array $params list of parameters for the command
* @return array|bool|null|string Dependend on the executed command this method
* will return different data types:
*
* true for commands that return "status reply".string for commands that return "integer reply"
* as the value is in the range of a signed 64 bit integer.string or null for commands that return "bulk reply".array for commands that return "Multi-bulk replies".
* See {@link http://redis.io/topics/protocol redis protocol description}
* for details on the mentioned reply types.
* @trows CException for commands that return {@link http://redis.io/topics/protocol#error-reply error reply}.
*/
public function executeCommand($name,$params=array())
{
if($this->_socket===null)
$this->connect();
array_unshift($params,$name);
$command='*'.count($params)."\r\n";
foreach($params as $arg)
$command.='$'.strlen($arg)."\r\n".$arg."\r\n";
fwrite($this->_socket,$command);
return $this->parseResponse(implode(' ',$params));
}
/**
* Reads the result from socket and parses it
* @return array|bool|null|string
* @throws CException socket or data problems
*/
private function parseResponse()
{
if(($line=fgets($this->_socket))===false)
throw new CException('Failed reading data from redis connection socket.');
$type=$line[0];
$line=substr($line,1,-2);
switch($type)
{
case '+': // Status reply
return true;
case '-': // Error reply
throw new CException('Redis error: '.$line);
case ':': // Integer reply
// no cast to int as it is in the range of a signed 64 bit integer
return $line;
case '$': // Bulk replies
if($line=='-1')
return null;
$length=$line+2;
$data='';
while($length>0)
{
if(($block=fread($this->_socket,$length))===false)
throw new CException('Failed reading data from redis connection socket.');
$data.=$block;
$length-=(function_exists('mb_strlen') ? mb_strlen($block,'8bit') : strlen($block));
}
return substr($data,0,-2);
case '*': // Multi-bulk replies
$count=(int)$line;
$data=array();
for($i=0;$i<$count;$i++)
$data[]=$this->parseResponse();
return $data;
default:
throw new CException('Unable to parse data received from redis.');
}
}
/**
* Retrieves a value from cache with a specified key.
* This is the implementation of the method declared in the parent class.
* @param string $key a unique key identifying the cached value
* @return string|boolean the value stored in cache, false if the value is not in the cache or expired.
*/
protected function getValue($key)
{
return $this->executeCommand('GET',array($key));
}
/**
* Retrieves multiple values from cache with the specified keys.
* @param array $keys a list of keys identifying the cached values
* @return array a list of cached values indexed by the keys
*/
protected function getValues($keys)
{
$response=$this->executeCommand('MGET',$keys);
$result=array();
$i=0;
foreach($keys as $key)
$result[$key]=$response[$i++];
return $result;
}
/**
* Stores a value identified by a key in cache.
* This is the implementation of the method declared in the parent class.
*
* @param string $key the key identifying the value to be cached
* @param string $value the value to be cached
* @param integer $expire the number of seconds in which the cached value will expire. 0 means never expire.
* @return boolean true if the value is successfully stored into cache, false otherwise
*/
protected function setValue($key,$value,$expire)
{
if ($expire==0)
return (bool)$this->executeCommand('SET',array($key,$value));
return (bool)$this->executeCommand('SETEX',array($key,$expire,$value));
}
/**
* Stores a value identified by a key into cache if the cache does not contain this key.
* This is the implementation of the method declared in the parent class.
*
* @param string $key the key identifying the value to be cached
* @param string $value the value to be cached
* @param integer $expire the number of seconds in which the cached value will expire. 0 means never expire.
* @return boolean true if the value is successfully stored into cache, false otherwise
*/
protected function addValue($key,$value,$expire)
{
if ($expire == 0)
return (bool)$this->executeCommand('SETNX',array($key,$value));
if($this->executeCommand('SETNX',array($key,$value)))
{
$this->executeCommand('EXPIRE',array($key,$expire));
return true;
}
else
return false;
}
/**
* Deletes a value with the specified key from cache
* This is the implementation of the method declared in the parent class.
* @param string $key the key of the value to be deleted
* @return boolean if no error happens during deletion
*/
protected function deleteValue($key)
{
return (bool)$this->executeCommand('DEL',array($key));
}
/**
* Deletes all values from cache.
* This is the implementation of the method declared in the parent class.
* @return boolean whether the flush operation was successful.
*/
protected function flushValues()
{
return $this->executeCommand('FLUSHDB');
}
}