diff options
Diffstat (limited to 'framework/Caching/TSqliteCache.php')
| -rw-r--r-- | framework/Caching/TSqliteCache.php | 102 |
1 files changed, 30 insertions, 72 deletions
diff --git a/framework/Caching/TSqliteCache.php b/framework/Caching/TSqliteCache.php index 92cc46a6..dc4bf13f 100644 --- a/framework/Caching/TSqliteCache.php +++ b/framework/Caching/TSqliteCache.php @@ -25,14 +25,12 @@ * - {@link get} : retrieve the value with a key (if any) from cache
* - {@link set} : store the value with a key into cache
* - {@link add} : store the value only if cache does not have this key
- * - {@link replace} : store the value only if cache has this key
* - {@link delete} : delete the value with the specified key from cache
* - {@link flush} : delete all values from cache
*
* Each value is associated with an expiration time. The {@link get} operation
- * ensures that any expired value will not be returned. The expiration time can
- * be specified by the number of seconds (maximum 60*60*24*30)
- * or a UNIX timestamp. A expiration time 0 represents never expire.
+ * ensures that any expired value will not be returned. The expiration time by
+ * the number of seconds. A expiration time 0 represents never expire.
*
* By definition, cache does not ensure the existence of a value
* even if it never expires. Cache is not meant to be an persistent storage.
@@ -40,7 +38,7 @@ * Do not use the same database file for multiple applications using TSqliteCache.
* Also note, cache is shared by all user sessions of an application.
*
- * To use this module, the sqlite PHP extension must be loaded. Sqlite extension
+ * To use this module, the sqlite PHP extension must be loaded. Note, Sqlite extension
* is no longer loaded by default since PHP 5.1.
*
* Some usage examples of TSqliteCache are as follows,
@@ -55,8 +53,10 @@ * If loaded, TSqliteCache will register itself with {@link TApplication} as the
* cache module. It can be accessed via {@link TApplication::getCache()}.
*
- * TMemCache may be configured in application configuration file as follows
+ * TSqliteCache may be configured in application configuration file as follows
+ * <code>
* <module id="cache" type="System.Caching.TSqliteCache" DbFile="Application.Data.site" />
+ * </code>
* where {@link getDbFile DbFile} is a property specifying the location of the
* SQLite DB file (in the namespace format).
*
@@ -65,7 +65,7 @@ * @package System.Caching
* @since 3.0
*/
-class TSqliteCache extends TModule implements ICache
+class TSqliteCache extends TCache
{
/**
* name of the table storing cache data
@@ -75,10 +75,6 @@ class TSqliteCache extends TModule implements ICache * extension of the db file name
*/
const DB_FILE_EXT='.db';
- /**
- * maximum number of seconds specified as expire
- */
- const EXPIRE_LIMIT=2592000; // 30 days
/**
* @var boolean if the module has been initialized
@@ -125,7 +121,7 @@ class TSqliteCache extends TModule implements ICache {
if($res->numRows()===0)
{
- if($this->_db->query('CREATE TABLE '.self::CACHE_TABLE.' (key CHAR(128) PRIMARY KEY, value BLOB, serialized INT, expire INT)')===false)
+ if($this->_db->query('CREATE TABLE '.self::CACHE_TABLE.' (key CHAR(128) PRIMARY KEY, value BLOB, expire INT)')===false)
throw new TConfigurationException('sqlitecache_table_creation_failed',sqlite_error_string(sqlite_last_error()));
}
}
@@ -133,7 +129,7 @@ class TSqliteCache extends TModule implements ICache throw new TConfigurationException('sqlitecache_table_creation_failed',sqlite_error_string(sqlite_last_error()));
$this->_db->query('DELETE FROM '.self::CACHE_TABLE.' WHERE expire<>0 AND expire<'.time());
$this->_initialized=true;
- $this->getApplication()->setCache($this);
+ parent::init($config);
}
/**
@@ -159,96 +155,58 @@ class TSqliteCache extends TModule implements ICache /**
* Retrieves a value from cache with a specified key.
- * @return mixed the value stored in cache, false if the value is not in the cache or expired.
+ * This is the implementation of the method declared in the parent class.
+ * @param string a unique key identifying the cached value
+ * @return string the value stored in cache, false if the value is not in the cache or expired.
*/
- public function get($key)
+ protected function getValue($key)
{
- $sql='SELECT serialized,value FROM '.self::CACHE_TABLE.' WHERE key=\''.md5($key).'\' AND (expire=0 OR expire>'.time().')';
+ $sql='SELECT value FROM '.self::CACHE_TABLE.' WHERE key=\''.$key.'\' AND (expire=0 OR expire>'.time().')';
if(($ret=$this->_db->query($sql))!=false && ($row=$ret->fetch(SQLITE_ASSOC))!==false)
- return $row['serialized']?Prado::unserialize($row['value']):$row['value'];
+ return $row['value'];
else
return false;
}
/**
- * Stores a value identified by a key into cache.
- * If the cache already contains such a key, the existing value and
- * expiration time will be replaced with the new ones.
- *
- * Note, avoid using this method whenever possible. Database insertion is
- * very expensive. Try using {@link add} instead, which will not store the value
- * if the key is already in cache.
+ * Stores a value identified by a key in cache.
+ * This is the implementation of the method declared in the parent class.
*
* @param string the key identifying the value to be cached
- * @param mixed the value to be cached
- * @param integer the expiration time of the value,
- * 0 means never expire,
- * a number less or equal than 60*60*24*30 means the number of seconds that the value will remain valid.
- * a number greater than 60*60*24*30 means a UNIX timestamp after which the value will expire.
+ * @param string the value to be cached
+ * @param integer the number of seconds in which the cached value will expire. 0 means never expire.
* @return boolean true if the value is successfully stored into cache, false otherwise
*/
- public function set($key,$value,$expire=0)
+ protected function setValue($key,$value,$expire)
{
- $serialized=is_string($value)?0:1;
- $value1=sqlite_escape_string($serialized?Prado::serialize($value):$value);
- if($expire && $expire<=self::EXPIRE_LIMIT)
- $expire=time()+$expire;
- $sql='REPLACE INTO '.self::CACHE_TABLE.' VALUES(\''.md5($key).'\',\''.$value1.'\','.$serialized.','.$expire.')';
+ $sql='REPLACE INTO '.self::CACHE_TABLE.' VALUES(\''.$key.'\',\''.sqlite_escape_string($value).'\','.$expire.')';
return $this->_db->query($sql)!==false;
}
/**
* Stores a value identified by a key into cache if the cache does not contain this key.
- * Nothing will be done if the cache already contains the key.
+ * This is the implementation of the method declared in the parent class.
+ *
* @param string the key identifying the value to be cached
- * @param mixed the value to be cached
- * @param integer the expiration time of the value,
- * 0 means never expire,
- * a number less or equal than 60*60*24*30 means the number of seconds that the value will remain valid.
- * a number greater than 60*60*24*30 means a UNIX timestamp after which the value will expire.
+ * @param string the value to be cached
+ * @param integer 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
*/
- public function add($key,$value,$expire=0)
+ protected function addValue($key,$value,$expire)
{
- $serialized=is_string($value)?0:1;
- $value1=sqlite_escape_string($serialized?Prado::serialize($value):$value);
- if($expire && $expire<=self::EXPIRE_LIMIT)
- $expire=time()+$expire;
- $sql='INSERT INTO '.self::CACHE_TABLE.' VALUES(\''.md5($key).'\',\''.$value1.'\','.$serialized.','.$expire.')';
+ $sql='INSERT INTO '.self::CACHE_TABLE.' VALUES(\''.$key.'\',\''.sqlite_escape_string($value).'\','.$expire.')';
return @$this->_db->query($sql)!==false;
}
/**
- * Stores a value identified by a key into cache only if the cache contains this key.
- * The existing value and expiration time will be overwritten with the new ones.
- * @param string the key identifying the value to be cached
- * @param mixed the value to be cached
- * @param integer the expiration time of the value,
- * 0 means never expire,
- * a number less or equal than 60*60*24*30 means the number of seconds that the value will remain valid.
- * a number greater than 60*60*24*30 means a UNIX timestamp after which the value will expire.
- * @return boolean true if the value is successfully stored into cache, false otherwise
- */
- public function replace($key,$value,$expire=0)
- {
- $serialized=is_string($value)?0:1;
- $value1=sqlite_escape_string($serialized?Prado::serialize($value):$value);
- if($expire && $expire<=self::EXPIRE_LIMIT)
- $expire=time()+$expire;
- $sql='UPDATE '.self::CACHE_TABLE.' SET value=\''.$value1.'\', serialized='.$serialized.',expire='.$expire.' WHERE key=\''.md5($key).'\'';
- $this->_db->query($sql);
- $ret=$this->_db->query('SELECT serialized FROM '.self::CACHE_TABLE.' WHERE key=\''.md5($key).'\'');
- return ($ret!=false && $ret->numRows()>0);
- }
-
- /**
* Deletes a value with the specified key from cache
+ * This is the implementation of the method declared in the parent class.
* @param string the key of the value to be deleted
* @return boolean if no error happens during deletion
*/
- public function delete($key)
+ protected function deleteValue($key)
{
- $sql='DELETE FROM '.self::CACHE_TABLE.' WHERE key=\''.md5($key).'\'';
+ $sql='DELETE FROM '.self::CACHE_TABLE.' WHERE key=\''.$key.'\'';
return $this->_db->query($sql)!==false;
}
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