nextcloud/3rdparty/aws-sdk/lib/cachecore/cachepdo.class.php

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<?php
/**
* Container for all PDO-based cache methods. Inherits additional methods from <CacheCore>. Adheres
* to the ICacheCore interface.
*
* @version 2012.04.17
* @copyright 2006-2012 Ryan Parman
* @copyright 2006-2010 Foleeo, Inc.
* @copyright 2012 Amazon.com, Inc. or its affiliates.
* @copyright 2008-2010 Contributors
* @license http://opensource.org/licenses/bsd-license.php Simplified BSD License
* @link http://github.com/skyzyx/cachecore CacheCore
* @link http://getcloudfusion.com CloudFusion
* @link http://php.net/pdo PDO
*/
class CachePDO extends CacheCore implements ICacheCore
{
/**
* Reference to the PDO connection object.
*/
var $pdo = null;
/**
* Holds the parsed URL components.
*/
var $dsn = null;
/**
* Holds the PDO-friendly version of the connection string.
*/
var $dsn_string = null;
/**
* Holds the prepared statement for creating an entry.
*/
var $create = null;
/**
* Holds the prepared statement for reading an entry.
*/
var $read = null;
/**
* Holds the prepared statement for updating an entry.
*/
var $update = null;
/**
* Holds the prepared statement for resetting the expiry of an entry.
*/
var $reset = null;
/**
* Holds the prepared statement for deleting an entry.
*/
var $delete = null;
/**
* Holds the response of the read so we only need to fetch it once instead of doing
* multiple queries.
*/
var $store_read = null;
/*%******************************************************************************************%*/
// CONSTRUCTOR
/**
* Constructs a new instance of this class.
*
* Tested with [MySQL 5.0.x](http://mysql.com), [PostgreSQL](http://postgresql.com), and
* [SQLite 3.x](http://sqlite.org). SQLite 2.x is assumed to work. No other PDO-supported databases have
* been tested (e.g. Oracle, Microsoft SQL Server, IBM DB2, ODBC, Sybase, Firebird). Feel free to send
* patches for additional database support.
*
* See <http://php.net/pdo> for more information.
*
* @param string $name (Required) A name to uniquely identify the cache object.
* @param string $location (Optional) The location to store the cache object in. This may vary by cache method. The default value is NULL.
* @param integer $expires (Optional) The number of seconds until a cache object is considered stale. The default value is 0.
* @param boolean $gzip (Optional) Whether data should be gzipped before being stored. The default value is true.
* @return object Reference to the cache object.
*/
public function __construct($name, $location = null, $expires = 0, $gzip = true)
{
// Make sure the name is no longer than 40 characters.
$name = sha1($name);
// Call parent constructor and set id.
parent::__construct($name, $location, $expires, $gzip);
$this->id = $this->name;
$options = array();
// Check if the location contains :// (e.g. mysql://user:pass@hostname:port/table)
if (stripos($location, '://') === false)
{
// No? Just pass it through.
$this->dsn = parse_url($location);
$this->dsn_string = $location;
}
else
{
// Yes? Parse and set the DSN
$this->dsn = parse_url($location);
$this->dsn_string = $this->dsn['scheme'] . ':host=' . $this->dsn['host'] . ((isset($this->dsn['port'])) ? ';port=' . $this->dsn['port'] : '') . ';dbname=' . substr($this->dsn['path'], 1);
}
// Make sure that user/pass are defined.
$user = isset($this->dsn['user']) ? $this->dsn['user'] : null;
$pass = isset($this->dsn['pass']) ? $this->dsn['pass'] : null;
// Set persistence for databases that support it.
switch ($this->dsn['scheme'])
{
case 'mysql': // MySQL
case 'pgsql': // PostgreSQL
$options[PDO::ATTR_PERSISTENT] = true;
break;
}
// Instantiate a new PDO object with a persistent connection.
$this->pdo = new PDO($this->dsn_string, $user, $pass, $options);
// Define prepared statements for improved performance.
$this->create = $this->pdo->prepare("INSERT INTO cache (id, expires, data) VALUES (:id, :expires, :data)");
$this->read = $this->pdo->prepare("SELECT id, expires, data FROM cache WHERE id = :id");
$this->reset = $this->pdo->prepare("UPDATE cache SET expires = :expires WHERE id = :id");
$this->delete = $this->pdo->prepare("DELETE FROM cache WHERE id = :id");
}
/**
* Creates a new cache.
*
* @param mixed $data (Required) The data to cache.
* @return boolean Whether the operation was successful.
*/
public function create($data)
{
$data = serialize($data);
$data = $this->gzip ? gzcompress($data) : $data;
$this->create->bindParam(':id', $this->id);
$this->create->bindParam(':data', $data);
$this->create->bindParam(':expires', $this->generate_timestamp());
return (bool) $this->create->execute();
}
/**
* Reads a cache.
*
* @return mixed Either the content of the cache object, or boolean `false`.
*/
public function read()
{
if (!$this->store_read)
{
$this->read->bindParam(':id', $this->id);
$this->read->execute();
$this->store_read = $this->read->fetch(PDO::FETCH_ASSOC);
}
if ($this->store_read)
{
$data = $this->store_read['data'];
$data = $this->gzip ? gzuncompress($data) : $data;
return unserialize($data);
}
return false;
}
/**
* Updates an existing cache.
*
* @param mixed $data (Required) The data to cache.
* @return boolean Whether the operation was successful.
*/
public function update($data)
{
$this->delete();
return $this->create($data);
}
/**
* Deletes a cache.
*
* @return boolean Whether the operation was successful.
*/
public function delete()
{
$this->delete->bindParam(':id', $this->id);
return $this->delete->execute();
}
/**
* Checks whether the cache object is expired or not.
*
* @return boolean Whether the cache is expired or not.
*/
public function is_expired()
{
if ($this->timestamp() + $this->expires < time())
{
return true;
}
return false;
}
/**
* Retrieves the timestamp of the cache.
*
* @return mixed Either the Unix time stamp of the cache creation, or boolean `false`.
*/
public function timestamp()
{
if (!$this->store_read)
{
$this->read->bindParam(':id', $this->id);
$this->read->execute();
$this->store_read = $this->read->fetch(PDO::FETCH_ASSOC);
}
if ($this->store_read)
{
$value = $this->store_read['expires'];
// If 'expires' isn't yet an integer, convert it into one.
if (!is_numeric($value))
{
$value = strtotime($value);
}
$this->timestamp = date('U', $value);
return $this->timestamp;
}
return false;
}
/**
* Resets the freshness of the cache.
*
* @return boolean Whether the operation was successful.
*/
public function reset()
{
$this->reset->bindParam(':id', $this->id);
$this->reset->bindParam(':expires', $this->generate_timestamp());
return (bool) $this->reset->execute();
}
/**
* Returns a list of supported PDO database drivers. Identical to <PDO::getAvailableDrivers()>.
*
* @return array The list of supported database drivers.
* @link http://php.net/pdo.getavailabledrivers PHP Method
*/
public function get_drivers()
{
return PDO::getAvailableDrivers();
}
/**
* Returns a timestamp value apropriate to the current database type.
*
* @return mixed Timestamp for MySQL and PostgreSQL, integer value for SQLite.
*/
protected function generate_timestamp()
{
// Define 'expires' settings differently.
switch ($this->dsn['scheme'])
{
// These support timestamps.
case 'mysql': // MySQL
case 'pgsql': // PostgreSQL
$expires = date(DATE_FORMAT_MYSQL, time());
break;
// These support integers.
case 'sqlite': // SQLite 3
case 'sqlite2': // SQLite 2
$expires = time();
break;
}
return $expires;
}
}
/*%******************************************************************************************%*/
// EXCEPTIONS
class CachePDO_Exception extends CacheCore_Exception {}