* @copyright 2012 by RalfBecker@outdoor-training.de
* @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
* @package etemplate
* @subpackage api
* @version $Id$
*/
/**
* Ajax log file viewer (tail -f)
*
* To not allow to view arbitrary files, allowed filenames are stored in the session.
* Class fetches log-file periodically in chunks for 8k.
* If fetch returns no new content next request will be in 2s, otherwise in 200ms.
* As logfiles can be quiet huge, we display at max the last 32k of it!
*
* Example usage:
*
* $error_log = new egw_tail('/var/log/apache2/error_log');
* echo $error_log->show();
*
* Strongly prefered for security reasons is to use a path relative to EGroupware's files_dir,
* eg. new egw_tail('groupdav/somelog')!
*/
class egw_tail
{
/**
* Maximum size of single ajax request
*
* Currently also maximum size / 4 of displayed logfile content!
*/
const MAX_CHUNK_SIZE = 8192;
/**
* Contains allowed filenames to display, we can NOT allow to display arbitrary files!
*
* @param array
*/
protected $filenames;
/**
* Filename class is instanciated to view, set by constructor
*
* @param string
*/
protected $filename;
/**
* Constructor
*
* @param string $filename=null if not starting with as slash relative to EGw files dir (this is strongly prefered for security reasons)
*/
public function __construct($filename=null)
{
$this->filenames =& egw_cache::getSession('phpgwapi', __CLASS__);
if ($filename)
{
$this->filename = $filename;
if (!in_array($filename,$this->filenames)) $this->filenames[] = $filename;
}
}
/**
* Ajax callback to load next chunk of log-file
*
* @param string $filename
* @param int $start=0 last position in log-file
*/
public function ajax_chunk($filename,$start=0)
{
if (!in_array($filename,$this->filenames))
{
throw new egw_exception_wrong_parameter("Not allowed to view '$filename'!");
}
if ($filename[0] != '/') $filename = $GLOBALS['egw_info']['server']['files_dir'].'/'.$filename;
if (!$start || $start < 0)
{
$start = filesize($filename) - 4*self::MAX_CHUNK_SIZE;
if ($start < 0) $start = 0;
}
$content = file_get_contents($filename, false, null, $start, self::MAX_CHUNK_SIZE);
$length = bytes($content);
$response = egw_json_response::get();
$response->data(array( // send all responses as data
'next' => $start + $length,
'length' => $length,
'content' => $content,
));
}
/**
* Return html & javascript for logviewer
*
* @param string $id='log'
* @return string
*/
public function show($id='log')
{
if (!isset($this->filename))
{
throw new egw_exception_wrong_parameter("Must be instanciated with filename!");
}
return '
';
}
}
// some testcode, if this file is called via it's URL
if (isset($_SERVER['SCRIPT_FILENAME']) && $_SERVER['SCRIPT_FILENAME'] == __FILE__)
{
$GLOBALS['egw_info'] = array(
'flags' => array(
'currentapp' => 'admin',
),
);
include_once '../../header.inc.php';
$error_log = new egw_tail($file='/opt/local/apache2/logs/error_log');
echo "$file
\n";
echo $error_log->show();
}