classes/class.ilLinkChecker.php

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<?php
/*
        +-----------------------------------------------------------------------------+
        | ILIAS open source                                                           |
        +-----------------------------------------------------------------------------+
        | Copyright (c) 1998-2001 ILIAS open source, University of Cologne            |
        |                                                                             |
        | This program is free software; you can redistribute it and/or               |
        | modify it under the terms of the GNU General Public License                 |
        | as published by the Free Software Foundation; either version 2              |
        | of the License, or (at your option) any later version.                      |
        |                                                                             |
        | This program is distributed in the hope that it will be useful,             |
        | but WITHOUT ANY WARRANTY; without even the implied warranty of              |
        | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               |
        | GNU General Public License for more details.                                |
        |                                                                             |
        | You should have received a copy of the GNU General Public License           |
        | along with this program; if not, write to the Free Software                 |
        | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. |
        +-----------------------------------------------------------------------------+
*/

class ilLinkChecker
{
        var $db = null;
        var $log_messages = array();
        var $invalid_links = array();

        var $validate_all = true;
        var $mail_status = false;
        var $page_id = 0;


        function ilLinkChecker(&$db,$a_validate_all = true)
        {
                global $ilDB;

                define('DEBUG',1);
                define('SOCKET_TIMEOUT',5);

                $this->db =& $db;

                // SET GLOBAL DB HANDLER FOR STATIC METHODS OTHER CLASSES
                $ilDB =& $db;

                $this->validate_all = $a_validate_all;
        }

        function setCheckPeriod($a_period)
        {
                $this->period = $a_period;
        }
        function getCheckPeriod()
        {
                return $this->period;
        }

        function setMailStatus($a_status)
        {
                $this->mail_status = (bool) $a_status;
        }
        function getMailStatus()
        {
                return (bool) $this->mail_status;
        }

        function __setType($a_type)
        {
                $this->type = $a_type;
        }
        function __getType()
        {
                return $this->type;
        }

        function setObjId($a_page_id)
        {
                return $this->page_id = $a_page_id;
        }
        function getObjId()
        {
                return $this->page_id;
        }

        function getValidateAll()
        {
                return $this->validate_all ? true : false;
        }

        function getLogMessages()
        {
                return $this->log_messages ? $this->log_messages : array();
        }

        function getInvalidLinks()
        {
                return $this->invalid_links ? $this->invalid_links : array();
        }

        function getInvalidLinksFromDB()
        {
                $query = "SELECT * FROM link_check ".
                        "WHERE obj_id = '".$this->getObjId()."'";

                $res = $this->db->query($query);
                while($row = $res->fetchRow(DB_FETCHMODE_OBJECT))
                {
                        $invalid[] = array('page_id' => $row->page_id,
                                                           'url'         => $row->url);
                }

                return $invalid ? $invalid : array();
        }

        function getLastCheckTimestamp()
        {
                if($this->getValidateAll())
                {
                        $query = "SELECT MAX(last_check) as last_check FROM link_check ";
                }
                else
                {
                        $query = "SELECT MAX(last_check) as last_check FROM link_check ".
                                "WHERE obj_id = '".$this->getObjId()."'";
                }
                $row = $this->db->getRow($query,DB_FETCHMODE_OBJECT);

                return $row->last_check ? $row->last_check : 0;
        }

        function checkWebResourceLinks()
        {
                $pages = array();

                $this->__setType('webr');
                $this->__clearLogMessages();
                $this->__clearInvalidLinks();
                $this->__appendLogMessage('LinkChecker: Start checkLinks()');

                if(count($invalid = $this->__validateLinks($this->__getWebResourceLinks())))
                {
                        foreach($invalid as $invalid_item)
                        {
                                $this->__appendLogMessage('LinkChecker: found invalid link: '.$invalid_item['complete']);
                                $this->__appendInvalidLink($invalid_item);
                        }
                }
                
                $this->__appendLogMessage('LinkChecker: End checkLinks()');
                $this->__saveInDB();
                
                $this->__sendMail();
                
                return $this->getInvalidLinks();
        }
        
        function checkLinks()
        {
                $pages = array();

                $this->__setType('lm');
                $this->__clearLogMessages();
                $this->__clearInvalidLinks();
                $this->__appendLogMessage('LinkChecker: Start checkLinks()');

                if(!$this->getValidateAll() and !$this->getObjId())
                {
                        echo "ilLinkChecker::checkLinks() No Page id given";

                        return false;
                }
                elseif(!$this->getValidateAll() and $this->getObjId())
                {
                        $query = "SELECT * FROM page_object ".
                                "WHERE parent_id = '".$this->getObjId()."' ".
                                "AND parent_type = 'lm'";

                        $res = $this->db->query($query);
                        while($row = $res->fetchRow(DB_FETCHMODE_OBJECT))
                        {
                                $pages[] = array('page_id' => $row->page_id,
                                                                 'content' => $row->content,
                                                                 'type'  => $row->parent_type);
                        }
                }
                elseif($this->getValidateAll())
                {
                        $query = "SELECT * FROM page_object ".
                                "WHERE parent_type = 'lm'";

                        $res = $this->db->query($query);
                        while($row = $res->fetchRow(DB_FETCHMODE_OBJECT))
                        {
                                $pages[] = array('page_id' => $row->page_id,
                                                                 'content' => $row->content,
                                                                 'type'  => $row->parent_type);
                        }
                }

                // VALIDATE
                foreach($pages as $page)
                {
                        if(count($invalid = $this->__validateLinks($this->__getLinks($page))))
                        {
                                foreach($invalid as $invalid_item)
                                {
                                        $this->__appendLogMessage('LinkChecker: found invalid link: '.$invalid_item['complete']);
                                        $this->__appendInvalidLink($invalid_item);
                                }
                        }
                }
                
                $this->__appendLogMessage('LinkChecker: End checkLinks()');
                $this->__saveInDB();

                $this->__sendMail();

                return $this->getInvalidLinks();
        }

        function checkPear()
        {
                if(!@include_once('HTTP/Request.php'))
                {
                        return false;
                }
                return true;
        }
                

        // PRIVATE
        function __txt($language,$key,$module = 'common')
        {
                $query = "SELECT value FROM lng_data ".
                        "WHERE module = '".$module."' ".
                        "AND identifier = '".$key."' ".
                        "AND lang_key = '".$language."'";

                $res = $this->db->query($query);
                while($row = $res->fetchRow(DB_FETCHMODE_OBJECT))
                {
                        $value = $row->value;
                }
                if(!$value)
                {
                        $query = "SELECT value FROM lng_data ".
                                "WHERE module = '".$module."' ".
                                "AND identifier = '".$key."' ".
                                "AND lang_key = 'en'";
                        
                        $res = $this->db->query($query);
                        while($row = $res->fetchRow(DB_FETCHMODE_OBJECT))
                        {
                                $value = $row->value;
                        }
                }
                return $value ? $value : '-'.$key.'-';
        }

        function __fetchUserData($a_usr_id)
        {
                $query = "SELECT email FROM usr_data WHERE usr_id = '".$a_usr_id."'";

                $row = $this->db->getRow($query,DB_FETCHMODE_OBJECT);

                $data['email'] = $row->email;

                $query = "SELECT * FROM usr_pref ".
                        "WHERE usr_id = '".$a_usr_id."' ".
                        "AND keyword = 'language'";

                $row = $this->db->getRow($query,DB_FETCHMODE_OBJECT);

                $data['lang'] = $row->value;

                return $data;
        }

        function __getTitle($a_lm_obj_id)
        {
                $query = "SELECT title FROM object_data ".
                        "WHERE obj_id = '".$a_lm_obj_id."'";

                $row = $this->db->getRow($query,DB_FETCHMODE_OBJECT);

                return $row->title;
        }

        function __sendMail()
        {
                global $ilUser;


                if(!count($notify = $this->__getNotifyLinks()))
                {
                        // Nothing to do
                        return true;
                }
                if(!$this->getMailStatus())
                {
                        return true;
                }

                include_once './classes/class.ilLinkCheckNotify.php';
                
                foreach(ilLinkCheckNotify::_getAllNotifiers($this->db) as $usr_id => $obj_ids)
                {
                        if(!is_object($tmp_user =& ilObjectFactory::getInstanceByObjId($usr_id,false)))
                        {
                                $this->__appendLogMessage('LinkChecker: Cannot find user with id: '.$usr_id);
                                continue;
                        }

                        $counter = 0;
                        foreach($obj_ids as $obj_id)
                        {
                                if(!isset($notify[$obj_id]))
                                {
                                        continue;
                                }
                                ++$counter;

                                switch($this->__getType())
                                {
                                        case 'webr':
                                                $body .= $this->__txt($tmp_user->getLanguage(),'obj_webr');
                                                break;

                                        case 'lm':
                                        default:
                                                $body .= $this->__txt($tmp_user->getLanguage(),'lo');
                                                break;
                                }
                                                
                                $body .= ': ';
                                $body .= $this->__getTitle($obj_id)."\r\n";

                                // Print all invalid
                                foreach($notify[$obj_id] as $data)
                                {
                                        $body .= $data['url']."\r\n";
                                }
                                $body .= "\r\n";
                        }
                        if($counter)
                        {
                                include_once "classes/class.ilFormatMail.php";
                                
                                $umail = new ilFormatMail($tmp_user->getId());
                                $subject = $this->__txt($tmp_user->getLanguage(),'link_check_subject');
                        }

                        $umail->sendMail($tmp_user->getLogin(),"","",$subject,$body,array(),array("normal"));
                        $this->__appendLogMessage('LinkChecker: Sent mail to '.$tmp_user->getEmail());
                }
                                

        }

        function __getNotifyLinks()
        {
                return $this->notify ? $this->notify : array();
        }


        function __clearInvalidLinks()
        {
                $this->invalid_links = array();
        }
        function __appendInvalidLink($a_link)
        {
                $this->invalid_links[] = $a_link;
        }
                                        

        function __appendLogMessage($a_string)
        {
                $this->log_messages[] = $a_string;
        }
        function __clearLogMessages()
        {
                return $this->log_messages = array();
        }

        function __getLinks($a_page)
        {
                $matches = array();

                $pattern_complete = '/<ExtLink Href="([^"]*)">/';
                if(preg_match_all($pattern_complete,$a_page['content'],$matches))
                {
                        for($i = 0;$i < count($matches[0]); ++$i)
                        {
                                $url_data = parse_url($matches[1][$i]);
                                
                                // PUH, HTTP_REQUEST needs a beginning http://
                                if(!$url_data['scheme'])
                                {
                                        $matches[1][$i] = 'http://'.$matches[1][$i];
                                }

                                $lm_id = $this->__getObjIdByPageId($a_page['page_id']);
                                $link[] = array('page_id'  => $a_page['page_id'],
                                                                'obj_id'   => $lm_id,
                                                                'type'     => $a_page['type'],
                                                                'complete' => $matches[1][$i],
                                                                'scheme'   => isset($url_data['scheme']) ? $url_data['scheme'] : 'http',
                                                                'host'     => isset($url_data['host']) ? $url_data['host'] : $url_data['path']);
                        }
                }

                return $link ? $link : array();
        }

        function __getWebResourceLinks()
        {
                include_once 'link/classes/class.ilLinkResourceItems.php';

                $link_res_obj = new ilLinkResourceItems($this->getObjId());

                foreach($check_links = $link_res_obj->getCheckItems($this->getCheckPeriod()) as $item_data)
                {
                                $url_data = parse_url($item_data['target']);
                                
                                // PUH, HTTP_REQUEST needs a beginning http://
                                if(!$url_data['scheme'])
                                {
                                        $item_data['target'] = 'http://'.$item_data['target'];
                                }

                                $link[] = array('page_id'  => $item_data['link_id'],
                                                                'obj_id'   => $this->getObjId(),
                                                                'type'     => 'webr',
                                                                'complete' => $item_data['target'],
                                                                'scheme'   => isset($url_data['scheme']) ? $url_data['scheme'] : 'http',
                                                                'host'     => isset($url_data['host']) ? $url_data['host'] : $url_data['path']);
                }
                return $link ? $link : array();
        }                       

                

        function __validateLinks($a_links)
        {
                if(!@include_once('HTTP/Request.php'))
                {
                        $this->__appendLogMessage('LinkChecker: Pear HTTP_Request is not installed. Aborting');

                        return array();
                }

                foreach($a_links as $link)
                {
                        if(gethostbyname($link['host']) == $link['host'])
                        {
                                $invalid[] = $link;
                                continue;
                        }

                        if($link['scheme'] !== 'http' and $link['scheme'] !== 'https')
                        {
                                continue;
                        }

                        $req =& new HTTP_Request($link['complete']);
                        $req->sendRequest();

                        switch($req->getResponseCode())
                        {
                                // EVERYTHING OK
                                case '200':
                                        // In the moment 301 will be handled as ok
                                case '301':
                                case '302':
                                        break;

                                default:
                                        $link['http_status_code'] = $req->getResponseCode();
                                        $invalid[] = $link;
                                        break;
                        }
                }
                return $invalid ? $invalid : array();
        }

        function __getObjIdByPageId($a_page_id)
        {
                $query = "SELECT lm_id FROM lm_data ".
                        "WHERE obj_id = '".$a_page_id."'";

                $row = $this->db->getRow($query,DB_FETCHMODE_OBJECT);

                return $row->lm_id ? $row->lm_id : 0;
        }

        function __isInvalid($a_page_id, $a_url)
        {
                foreach($this->getInvalidLinks() as $link)
                {
                        if($link['page_id'] == $a_page_id and
                           substr($link['complete'],0,255) == $a_url)
                        {
                                return true;
                        }
                }
                return false;
        }

        function __saveInDB()
        {
                if($this->getMailStatus())
                {
                        $this->__checkNotify();
                }
                $this->__clearDBData();


                foreach($this->getInvalidLinks() as $link)
                {

                        $query = "INSERT INTO link_check ".
                                "SET page_id = '".$link['page_id']."', ".
                                "obj_id = '".$link['obj_id']."', ".
                                "url = '".substr($link['complete'],0,255)."', ".
                                "parent_type = '".$link['type']."', ".
                                "http_status_code = '".$link['http_status_code']."', ".
                                "last_check = '".time()."'";


                        $res = $this->db->query($query);
                }

                // delete old values
                
        }

        function __checkNotify()
        {
                foreach($this->getInvalidLinks() as $link)
                {
                        $query = "SELECT * FROM link_check ".
                                "WHERE page_id = '".$link['page_id']."' ".
                                "AND url = '".substr($link['complete'],0,255)."'";
                        $res = $this->db->query($query);
                        
                        if(!$res->numRows())
                        {
                                $this->notify["$link[obj_id]"][] = array('page_id' => $link['page_id'],
                                                                                                                 'url'     => $link['complete']);
                        }
                }
        }


        function __clearDBData()
        {
                if($this->getValidateAll())
                {
                        $query = "DELETE FROM link_check";
                }
                else
                {
                        $query = "DELETE FROM link_check ".
                                "WHERE obj_id = '".$this->getObjId()."'";
                }

                $this->db->query($query);

                return true;
        }
}
?>