php man page for sessionhandlerinterface

SESSIONHANDLERINTERFACE(3)						 1						SESSIONHANDLERINTERFACE(3)

The SessionHandlerInterface class

INTRODUCTION
       SessionHandlerInterface	is an interface which defines a prototype for creating a custom session handler. In order to pass a custom session
       handler to session_set_save_handler(3) using its OOP invocation, the class must implement this interface.

	Please note the callback methods of this class are designed to be called internally by PHP and are not meant to be called from	user-space
       code.

CLASS SYNOPSIS
       SessionHandlerInterface

       SessionHandlerInterface

       Methods

       o abstractpublic bool SessionHandlerInterface::close (void  )

       o abstractpublic bool SessionHandlerInterface::destroy (string  $session_id)

       o abstractpublic bool SessionHandlerInterface::gc (string  $maxlifetime)

       o abstractpublic bool SessionHandlerInterface::open (string  $save_path, string	$name)

       o abstractpublic string SessionHandlerInterface::read (string  $session_id)

       o abstractpublic bool SessionHandlerInterface::write (string  $session_id, string  $session_data)

       Example #1

	       Example using SessionHandlerInterface

	       The  following  example	provides  file based session storage similar to the PHP sessions default save handler $files. This example
	      could easily be extended to cover database storage using your favorite PHP supported database engine.

	       Note we use the OOP prototype with session_set_save_handler(3) and register the shutdown function using	the  function's  parameter
	      flag. This is generally advised when registering objects as session save handlers.

	      <?php
	      class MySessionHandler implements SessionHandlerInterface
	      {
		  private $savePath;

		  public function open($savePath, $sessionName)
		  {
		      $this->savePath = $savePath;
		      if (!is_dir($this->savePath)) {
			  mkdir($this->savePath, 0777);
		      }

		      return true;
		  }

		  public function close()
		  {
		      return true;
		  }

		  public function read($id)
		  {
		      return (string)@file_get_contents("$this->savePath/sess_$id");
		  }

		  public function write($id, $data)
		  {
		      return file_put_contents("$this->savePath/sess_$id", $data) === false ? false : true;
		  }

		  public function destroy($id)
		  {
		      $file = "$this->savePath/sess_$id";
		      if (file_exists($file)) {
			  unlink($file);
		      }

		      return true;
		  }

		  public function gc($maxlifetime)
		  {
		      foreach (glob("$this->savePath/sess_*") as $file) {
			  if (filemtime($file) + $maxlifetime < time() && file_exists($file)) {
			      unlink($file);
			  }
		      }

		      return true;
		  }
	      }

	      $handler = new MySessionHandler();
	      session_set_save_handler($handler, true);
	      session_start();

	      // proceed to set and retrieve values by key from $_SESSION

PHP Documentation Group 												SESSIONHANDLERINTERFACE(3)