* @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;
/**
* Methods allowed to call via menuaction
*
* @var array
*/
public $public_functions = array(
'download' => true,
);
/**
* 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 = $filename;
if (!$this->filenames || !in_array($filename,$this->filenames)) $this->filenames[] = $filename;
}
}
/**
* Ajax callback to load next chunk of log-file
*
* @param string $filename
* @param int $start=0 last position in log-file
* @throws egw_exception_wrong_parameter
*/
public function ajax_chunk($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 (file_exists($filename))
{
$size = filesize($filename);
if (!$start || $start < 0 || $start > $size || $size-$start > 4*self::MAX_CHUNK_SIZE)
{
$start = $size - 4*self::MAX_CHUNK_SIZE;
if ($start < 0) $start = 0;
}
$size = egw_vfs::hsize($size);
$content = file_get_contents($filename, false, null, $start, self::MAX_CHUNK_SIZE);
$length = bytes($content);
$writable = is_writable($filename) || is_writable(dirname($filename));
}
else
{
$start = $length = 0;
$content = '';
$writable = $size = false;
}
$response = egw_json_response::get();
$response->data(array( // send all responses as data
'size' => $size,
'writable' => $writable,
'next' => $start + $length,
'length' => $length,
'content' => $content,
));
}
/**
* Ajax callback to delete log-file
*
* @param string $filename
* @param boolean $truncate=false true: truncate file, false: delete file
* @throws egw_exception_wrong_parameter
*/
public function ajax_delete($filename,$truncate=false)
{
if (!in_array($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 ($truncate)
{
file_put_contents($filename, '');
}
else
{
unlink($filename);
}
}
/**
* Return html & javascript for logviewer
*
* @param string $header=null default $this->filename
* @return string
* @throws egw_exception_wrong_parameter
*/
public function show($header=null)
{
if (!isset($this->filename))
{
throw new egw_exception_wrong_parameter("Must be instanciated with filename!");
}
if (is_null($header)) $header = $this->filename;
return '
'.htmlspecialchars($header).'
'.html::form(
html::input('clear_log',lang('Clear window'),'button','id="clear_log"')."\n".
html::input('delete_log',lang('Delete file'),'button','id="purge_log"')."\n".
html::input('empty_log',lang('Empty file'),'button','id="empty_log"')."\n".
html::input('download_log',lang('Download'),'submit','id="download_log"'),
'','/index.php',array(
'menuaction' => 'phpgwapi.egw_tail.download',
'filename' => $this->filename,
)).'
';
}
/**
* Download a file specified per GET parameter (must be in $this->filesnames!)
*
* @throws egw_exception_wrong_parameter
*/
public function download()
{
$filename = $_GET['filename'];
if (!in_array($filename,$this->filenames))
{
throw new egw_exception_wrong_parameter("Not allowed to download '$filename'!");
}
html::content_header(basename($filename),'text/plain');
if ($filename[0] != '/') $filename = $GLOBALS['egw_info']['server']['files_dir'].'/'.$filename;
for($n=ob_get_level(); $n > 0; --$n) ob_end_clean(); // stop all output buffering, to NOT run into memory_limit
readfile($filename);
common::egw_exit();
}
}
// some testcode, if this file is called via it's URL (you need to uncomment and adapt filename!)
/*if (isset($_SERVER['SCRIPT_FILENAME']) && $_SERVER['SCRIPT_FILENAME'] == __FILE__)
{
$GLOBALS['egw_info'] = array(
'flags' => array(
'currentapp' => 'admin',
'nonavbar' => true,
),
);
include_once '../../header.inc.php';
$error_log = new egw_tail('/opt/local/apache2/logs/error_log');
echo $error_log->show();
}*/