rss-bridge/caches/SQLiteCache.php

129 lines
3.6 KiB
PHP

<?php
/**
* Cache based on SQLite 3 <https://www.sqlite.org>
*/
class SQLiteCache implements CacheInterface
{
protected $scope;
protected $key;
private $db = null;
public function __construct()
{
if (!extension_loaded('sqlite3')) {
throw new \Exception('"sqlite3" extension not loaded. Please check "php.ini"');
}
if (!is_writable(PATH_CACHE)) {
throw new \Exception('The cache folder is not writable');
}
$section = 'SQLiteCache';
$file = Configuration::getConfig($section, 'file');
if (empty($file)) {
throw new \Exception(sprintf('Configuration for %s missing.', $section));
}
if (dirname($file) == '.') {
$file = PATH_CACHE . $file;
} elseif (!is_dir(dirname($file))) {
throw new \Exception(sprintf('Invalid configuration for %s', $section));
}
if (!is_file($file)) {
// The instantiation creates the file
$this->db = new \SQLite3($file);
$this->db->enableExceptions(true);
$this->db->exec("CREATE TABLE storage ('key' BLOB PRIMARY KEY, 'value' BLOB, 'updated' INTEGER)");
} else {
$this->db = new \SQLite3($file);
$this->db->enableExceptions(true);
}
$this->db->busyTimeout(5000);
}
public function loadData()
{
$Qselect = $this->db->prepare('SELECT value FROM storage WHERE key = :key');
$Qselect->bindValue(':key', $this->getCacheKey());
$result = $Qselect->execute();
if ($result instanceof \SQLite3Result) {
$data = $result->fetchArray(\SQLITE3_ASSOC);
if (isset($data['value'])) {
return unserialize($data['value']);
}
}
return null;
}
public function saveData($data)
{
$Qupdate = $this->db->prepare('INSERT OR REPLACE INTO storage (key, value, updated) VALUES (:key, :value, :updated)');
$Qupdate->bindValue(':key', $this->getCacheKey());
$Qupdate->bindValue(':value', serialize($data));
$Qupdate->bindValue(':updated', time());
$Qupdate->execute();
return $this;
}
public function getTime()
{
$Qselect = $this->db->prepare('SELECT updated FROM storage WHERE key = :key');
$Qselect->bindValue(':key', $this->getCacheKey());
$result = $Qselect->execute();
if ($result instanceof \SQLite3Result) {
$data = $result->fetchArray(SQLITE3_ASSOC);
if (isset($data['updated'])) {
return $data['updated'];
}
}
return null;
}
public function purgeCache($seconds)
{
$Qdelete = $this->db->prepare('DELETE FROM storage WHERE updated < :expired');
$Qdelete->bindValue(':expired', time() - $seconds);
$Qdelete->execute();
}
public function setScope($scope)
{
if (is_null($scope) || !is_string($scope)) {
throw new \Exception('The given scope is invalid!');
}
$this->scope = $scope;
return $this;
}
public function setKey($key)
{
if (!empty($key) && is_array($key)) {
$key = array_map('strtolower', $key);
}
$key = json_encode($key);
if (!is_string($key)) {
throw new \Exception('The given key is invalid!');
}
$this->key = $key;
return $this;
}
private function getCacheKey()
{
if (is_null($this->key)) {
throw new \Exception('Call "setKey" first!');
}
return hash('sha1', $this->scope . $this->key, true);
}
}