Customize session storage method in PHP_PHP tutorial

Description

In PHP, you can store server session data on different media by defining session_set_save_handler, such as in files, in apc or memcache cache, or in a database. You can count the number of people online, or kick out the login status of specific members, etc.

Customizing session_set_save_handler basically uses custom reading and writing methods to override the system's default session reading and writing methods to achieve session management. Everyone is welcome to communicate. If you have any questions, please write to me.

Factory class

[php]
 
/**
* CHttpSession
* http session data storage engine
​*/ 
 
class CHttpSession { 
 
    private static $engine; 
    private static $gc_maxlifetime; 
 
    public static function engine( $enginer ) { 
        $enginer        = ucfirst( $enginer ); 
        $engineInstance = "CHttpSession{$enginer}"; 
        $filename       = SYS_MODULE . '/Session/' . $engineInstance . '.php'; 
 
        if ( !file_exists( $filename )) { 
            throw new Exception( 'Fatal: not found {$filename} file' ); 
        } 
        require( $filename ); 
 
        if ( !class_exists( $engineInstance ) ) { 
            throw new Exception( 'Fatal: not found {$engineInstance} object' ); 
        } 
 
        $handler    = new CHttpSession( new $engineInstance ); 
 
        ini_set( "session.save_handler", "user" ); 
        ini_set( 'apc.ttl', 3600 ); 
        ini_set( 'apc.user_ttl', 1200 ); 
        ini_set( 'apc.gc_ttl', 3600 ); 
 
        session_set_save_handler( 
            array($handler, 'open'), 
            array($handler, 'close'), 
            array($handler, 'read'), 
            array($handler, 'write'), 
            array($handler, 'destroy'), 
            array($handler, 'gc') 
        ); 
         
        if ( isset( $_COOKIE['PHPSESSID'] ) ) { 
            session_start( $_COOKIE['PHPSESSID'] ); 
        } 
        else { 
            session_start( ); 
            setcookie( 'PHPSESSID', session_id(), null, '/', COOKIE_DOMAIN ); 
        } 
    } 
 
    public function __construct( & $engine ) { 
        self::$engine = $engine; 
        self::$gc_maxlifetime = ini_get( 'session.gc_maxlifetime' ); 
    } 
 
    public function read( $id ) { 
        return self::$engine->fetch( 'session/'.$id ); 
    } 
 
    public function write ( $id , $data ) { 
        return self::$engine->add( 'session/'.$id, $data, self::$gc_maxlifetime ); 
    } 
 
    public function close ( ) { 
        return true; 
    } 
 
 
    public function destroy ( $id ) { 
        return self::$engine->delete( 'session/'.$id ); 
    } 
 
    public function __destruct ( ) { 
        session_write_close(); 
    } 
 
 
    public function gc ( $maxlifetime ) { 
        return true; 
    } 
 
 
    public function open ( $save_path , $session_name ) { 
        return true; 
    } 
}; 

具体方法

CHttpSessionFile

[php]
 
/**
* CFileHttpSession
* Session engine, stores sessions in the form of files, YPi framework’s default session storage engine
* SESSION_DIR sets the session file storage path
​*/ 
 
 
class CHttpSessionFile { 
 
    public function add( $key, $data, $cg_maxlifetime ) { 
        $filepath = substr( $key, 7 ); 
        file_put_contents( SESSION_DIR.$filepath, $data ); 
        return true; 
    } 
 
    public function fetch( $key ) { 
        $filepath = substr( $key, 7 ); 
        if ( !file_exists(SESSION_DIR.$filepath) ) { 
            file_put_contents( SESSION_DIR.$filepath, '' ); 
            return true; 
        } 
        return file_get_contents( SESSION_DIR.$filepath ); 
    } 
 
    public function delete( $key ) { 
        $filepath = substr( $key, 7 ); 
        if ( file_exists( SESSION_DIR.$filepath ) ) { 
            unlink( SESSION_DIR.$filepath ); 
        } 
        return true; 
    } 
}; 

CHttpSessionApc

[php]
 
/**
* CApcHttpSession
* Session engine, stores sessions in the form of APC cache
* SESSION_ENGINE Set the value to apc to enable APC to store the session
​*/ 
 
 
class CHttpSessionApc { 
 
    public function add( $key, $data, $cg_maxlifetime ) { 
        apc_store( $key, $data, $cg_maxlifetime ); 
        return true; 
    } 
 
    public function fetch( $key ) { 
        if ( !apc_exists( $key ) ) { 
            apc_store( $key, '' ); 
            return true; 
        } 
        return apc_fetch( $key ); 
    } 
 
    public function delete( $key ) { 
        if ( apc_exists( $key ) ) { 
            apc_delete( $key ); 
        } 
        return true; 
    } 
}; 

CHttpSessionMemcache

[php]
 
/**
*CMemcacheHttpSession
* Session engine, stores sessions in the form of memcache cache *
* SESSION_ENGINE Set the value to memcache to enable memcache to store the session
* MEMCACHE_HOST Set memcache server address
* MEMCACHE_PORT Set memcache server access port number
​*/ 
 
 
class CHttpSessionMemcache { 
 
    private static $memcache; 
 
    public function __constrct( $config ) { 
        self::$memcache = new Memcache; 
        self::$memcache->connect( MEMCACHE_HOST, MEMCACHE_PORT ); 
    } 
 
    public function __destroy() { 
        self::$memcache->close(); 
    } 
 
    public function add( $key, $data, $cg_maxlifetime ) { 
        return self::$memcache->add( $key, $data, $cg_maxlifetime ); 
    } 
 
    public function fetch( $key ) { 
        return self::$memcache->get( $key ); 
    } 
 
    public function delete( $key ) { 
        return self::$memcache->delete( $key ); 
    } 
}; 

实例说明

只需要把平时用的 session_start() 替换成以下的方法即可。

[php]
 
defined('SESSION_ENGINE')||define('SESSION_ENGINE', 'file'); 
require '../lib/CHttpSession.php'; 
 
CHttpSession::engine( SESSION_ENGINE ); 

摘自 yagas的专栏