Implements: Kohana_Cache_GarbageCollect | Cache_GarbageCollect | Kohana_Cache_Tagging | Cache_Tagging
Kohana Cache Sqlite Driver
Requires SQLite3 and PDO
Class declared in MODPATH/cache/classes/Cache/Sqlite.php on line 3.
integer 3600
string
$defaultdefault driver to use
string(4) "file"
Kohana_Cache
$instancesinstances
array(0)
Config
$_configarray(0)
PDO
$_dbDatabase resource
NULL
Delete a cache entry based on id
string
$id
required - Id boolean
public function delete($id)
{
// Prepare statement
$statement = $this->_db->prepare('DELETE FROM caches WHERE id = :id');
// Remove the entry
try {
$statement->execute([':id' => $this->_sanitize_id($id)]);
} catch (PDOException $e) {
throw new Cache_Exception('There was a problem querying the local SQLite3 cache. :error', [':error' => $e->getMessage()]);
}
return (bool) $statement->rowCount();
}
Delete all cache entries
boolean
public function delete_all()
{
// Prepare statement
$statement = $this->_db->prepare('DELETE FROM caches');
// Remove the entry
try {
$statement->execute();
} catch (PDOException $e) {
throw new Cache_Exception('There was a problem querying the local SQLite3 cache. :error', [':error' => $e->getMessage()]);
}
return (bool) $statement->rowCount();
}
Delete cache entries based on a tag
string
$tag
required - Tag boolean
public function delete_tag($tag)
{
// Prepare the statement
$statement = $this->_db->prepare('DELETE FROM caches WHERE tags LIKE :tag');
// Try to delete
try {
$statement->execute([':tag' => "%<{$tag}>%"]);
} catch (PDOException $e) {
throw new Cache_Exception('There was a problem querying the local SQLite3 cache. :error', [':error' => $e->getMessage()]);
}
return (bool) $statement->rowCount();
}
Find cache entries based on a tag
string
$tag
required - Tag array
public function find($tag)
{
// Prepare the statement
$statement = $this->_db->prepare('SELECT id, cache FROM caches WHERE tags LIKE :tag');
// Try to find
try {
if (!$statement->execute([':tag' => "%<{$tag}>%"])) {
return [];
}
} catch (PDOException $e) {
throw new Cache_Exception('There was a problem querying the local SQLite3 cache. :error', [':error' => $e->getMessage()]);
}
$result = [];
while ($row = $statement->fetchObject()) {
// Disable notices for unserializing
$ER = error_reporting(~E_NOTICE);
$result[$row->id] = unserialize($row->cache);
// Turn notices back on
error_reporting($ER);
}
return $result;
}
Garbage collection method that cleans any expired cache entries from the cache.
void
public function garbage_collect()
{
// Create the sequel statement
$statement = $this->_db->prepare('DELETE FROM caches WHERE expiration < :expiration');
try {
$statement->execute([':expiration' => time()]);
} catch (PDOException $e) {
throw new Cache_Exception('There was a problem querying the local SQLite3 cache. :error', [':error' => $e->getMessage()]);
}
}
Retrieve a value based on an id
string
$id
required - Id string
$default
= NULL - Default [Optional] Default value to return if id not found mixed
public function get($id, $default = null)
{
// Prepare statement
$statement = $this->_db->prepare('SELECT id, expiration, cache FROM caches WHERE id = :id LIMIT 0, 1');
// Try and load the cache based on id
try {
$statement->execute([':id' => $this->_sanitize_id($id)]);
} catch (PDOException $e) {
throw new Cache_Exception('There was a problem querying the local SQLite3 cache. :error', [':error' => $e->getMessage()]);
}
if (!$result = $statement->fetch(PDO::FETCH_OBJ)) {
return $default;
}
// If the cache has expired
if ($result->expiration != 0 and $result->expiration <= time()) {
// Delete it and return default value
$this->delete($id);
return $default;
}
// Otherwise return cached object
else {
// Disable notices for unserializing
$ER = error_reporting(~E_NOTICE);
// Return the valid cache data
$data = unserialize($result->cache);
// Turn notices back on
error_reporting($ER);
// Return the resulting data
return $data;
}
}
Set a value based on an id. Optionally add tags.
string
$id
required - Id mixed
$data
required - Data integer
$lifetime
= NULL - Lifetime [Optional] boolean
public function set($id, $data, $lifetime = null)
{
return (bool) $this->set_with_tags($id, $data, $lifetime);
}
Set a value based on an id. Optionally add tags.
string
$id
required - Id mixed
$data
required - Data integer
$lifetime
= NULL - Lifetime [Optional] array
$tags
= NULL - Tags [Optional] boolean
public function set_with_tags($id, $data, $lifetime = null, array $tags = null)
{
// Serialize the data
$data = serialize($data);
// Normalise tags
$tags = (null === $tags) ? null : ('<' . implode('>,<', $tags) . '>');
// Setup lifetime
if ($lifetime === null) {
$lifetime = (0 === Arr::get($this->_config, 'default_expire', null)) ? 0 : (Arr::get($this->_config, 'default_expire', Cache::DEFAULT_EXPIRE) + time());
} else {
$lifetime = (0 === $lifetime) ? 0 : ($lifetime + time());
}
// Prepare statement
// $this->exists() may throw Cache_Exception, no need to catch/rethrow
$statement = $this->exists($id) ? $this->_db->prepare('UPDATE caches SET expiration = :expiration, cache = :cache, tags = :tags WHERE id = :id') : $this->_db->prepare('INSERT INTO caches (id, cache, expiration, tags) VALUES (:id, :cache, :expiration, :tags)');
// Try to insert
try {
$statement->execute([':id' => $this->_sanitize_id($id), ':cache' => $data, ':expiration' => $lifetime, ':tags' => $tags]);
} catch (PDOException $e) {
throw new Cache_Exception('There was a problem querying the local SQLite3 cache. :error', [':error' => $e->getMessage()]);
}
return (bool) $statement->rowCount();
}
Overload the __clone() method to prevent cloning
void
final public function __clone()
{
throw new Cache_Exception('Cloning of Kohana_Cache objects is forbidden');
}
Getter and setter for the configuration. If no argument provided, the current configuration is returned. Otherwise the configuration is set to this class.
// Overwrite all configuration
$cache->config(['driver' => 'memcache', '...']);
// Set a new configuration setting
$cache->config('servers', ['foo' => 'bar', '...']);
// Get a configuration setting
$servers = $cache->config('servers);
mixed
$key
= NULL - Key to set to array, either array or config path mixed
$value
= NULL - Value to associate with key mixed
public function config($key = null, $value = null)
{
if ($key === null)
return $this->_config;
if (is_array($key)) {
$this->_config = $key;
} else {
if ($value === null)
return Arr::get($this->_config, $key);
$this->_config[$key] = $value;
}
return $this;
}
Creates a singleton of a Kohana Cache group. If no group is supplied the default cache group is used.
// Create an instance of the default group
$default_group = Cache::instance();
// Create an instance of a group
$foo_group = Cache::instance('foo');
// Access an instantiated group directly
$foo_group = Cache::$instances['default'];
string
$group
= NULL - The name of the cache group to use [Optional] Cache
public static function instance($group = null)
{
// If there is no group supplied
if ($group === null) {
// Use the default setting
$group = Cache::$default;
}
if (isset(Cache::$instances[$group])) {
// Return the current group if initiated already
return Cache::$instances[$group];
}
$config = Kohana::$config->load('cache');
if (!$config->offsetExists($group)) {
throw new Cache_Exception('Failed to load Kohana Cache group: :group', [':group' => $group]);
}
$config = $config->get($group);
// Create a new cache type instance
$cache_class = 'Cache_' . ucfirst($config['driver']);
Cache::$instances[$group] = new $cache_class($config);
// Return the instance
return Cache::$instances[$group];
}
Sets up the PDO SQLite table and initialises the PDO connection
array
$config
required - Configuration protected function __construct(array $config)
{
parent::__construct($config);
$database = Arr::get($this->_config, 'database', null);
if ($database === null) {
throw new Cache_Exception('Database path not available in Kohana Cache configuration');
}
// Load new Sqlite DB
$this->_db = new PDO('sqlite:' . $database);
// Test for existing DB
$result = $this->_db->query("SELECT * FROM sqlite_master WHERE name = 'caches' AND type = 'table'")->fetchAll();
// If there is no table, create a new one
if (0 == count($result)) {
$database_schema = Arr::get($this->_config, 'schema', null);
if ($database_schema === null) {
throw new Cache_Exception('Database schema not found in Kohana Cache configuration');
}
try {
// Create the caches table
$this->_db->query(Arr::get($this->_config, 'schema', null));
} catch (PDOException $e) {
throw new Cache_Exception('Failed to create new SQLite caches table with the following error : :error', [':error' => $e->getMessage()]);
}
}
}
Tests whether an id exists or not
string
$id
required - Id boolean
protected function exists($id)
{
$statement = $this->_db->prepare('SELECT id FROM caches WHERE id = :id');
try {
$statement->execute([':id' => $this->_sanitize_id($id)]);
} catch (PDOExeption $e) {
throw new Cache_Exception('There was a problem querying the local SQLite3 cache. :error', [':error' => $e->getMessage()]);
}
return (bool) $statement->fetchAll();
}
Replaces troublesome characters with underscores.
// Sanitize a cache id
$id = $this->_sanitize_id($id);
string
$id
required - Id of cache to sanitize string
protected function _sanitize_id($id)
{
// Change slashes and spaces to underscores
return str_replace(['/', '\\', ' '], '_', $id);
}