include/classes/UrlRewrite/UrlRewrite.class.php

   1 <?php
   2 /************************************************************************/
   3 /* ATutor                                                                                                                               */
   4 /************************************************************************/
   5 /* Copyright (c) 2002-2010                                              */
   6 /* Inclusive Design Institute                                           */
   7 /* http://atutor.ca                                                     */
   8 /* This program is free software. You can redistribute it and/or        */
   9 /* modify it under the terms of the GNU General Public License          */
  10 /* as published by the Free Software Foundation.                        */
  11 /************************************************************************/
  12 // $Id$
  13
  14 //Include all the classes for external rewrite rules
  15 require_once('ForumsUrl.class.php');
  16 require_once('ContentUrl.class.php');
  17 require_once('FileStorageUrl.class.php');
  18 require_once('TestsUrl.class.php');
  19 require_once('GlossaryUrl.class.php');
  20
  21 /**
  22 * UrlRewrite
  23 * Class for rewriting pretty urls.
  24 * @access       public
  25 * @author       Harris Wong
  26 * @package      UrlRewrite
  27 */
  28 class UrlRewrite  {
  29         // local variables
  30         var $path;              //the path of this script
  31         var $filename;  //script name
  32         var $query;             //the queries of the REQUEST
  33         var $isEmpty;   //true if path, filename, and query are empty
  34
  35         // constructor
  36         function UrlRewrite($path, $filename, $query) {
  37                 if ($path=='' && $filename=='' && $query==''){
  38                         $this->isEmpty = true;
  39                 } else {
  40                         $this->isEmpty = false;
  41                 }
  42                 $this->path = $path;
  43                 $this->filename = $filename;
  44                 $this->query = $query;
  45         }
  46
  47         /**
  48          * Returns the link that points to this object as a page.
  49          * @access public
  50          */
  51         function redirect(){
  52                 //redirect to that url.
  53                 return '/'.$this->getPage();
  54         }
  55
  56         /**
  57          * Parser for the pathinfo, return an array with mapped key values similar to the querystring.
  58          * @access      public
  59          * @return      array   key=>value, where keys and values have the same meaning as the ones in the query strings.
  60          */
  61         function parsePrettyQuery(){
  62                 global $_config;
  63                 $result = array();
  64
  65                 //return empty array if query is empty
  66                 if (empty($this->query)){
  67                         return $result;
  68                 }
  69
  70                 //if course_dir_name is disabled from admin.
  71                 if ($_config['pretty_url']==0){
  72                         return $this->query;
  73                 }
  74
  75                 //If the first char is /, cut it
  76                 if (strpos($this->query, '/') == 0){
  77                         $query_parts = explode('/', substr($this->query, 1));
  78                 } else {
  79                         $query_parts = explode('/', $this->query);
  80                 }
  81
  82                 //dynamically create the array
  83                 //assumption: pathinfo ALWAYS in the format of key1/value1/key2/value2/key3/value3/etc...
  84                 foreach ($query_parts as $array_index=>$key_value){
  85                         if($array_index%2 == 0 && $query_parts[$array_index]!=''){
  86                                 if (isset($query_parts[$array_index+1])) $result[$key_value] = $query_parts[$array_index+1];
  87                         }
  88                 }
  89                 return $result;
  90         }
  91
  92
  93         /**
  94          * Parser for the querystrings url
  95          * @access      public
  96          * @param       string  querystring
  97          * @return      array   an array of mapped keys and values like the querystrings.
  98          *
  99          * NOTE:        Stopped using this function since we've decided to dynamically create the URL.
 100          *                      See: parsePrettyQuery()
 101          */
 102         function parseQuery($query){
 103                 //return empty array if query is empty
 104                 if (empty($query)){
 105                         return array();
 106                 }
 107
 108                 parse_str($this->query, $result);
 109                 return $result;
 110         }
 111
 112
 113         /**
 114          * Construct the pretty url based on the given query.
 115          * @access      public
 116          * @param       string  the pathinfo query
 117          * @return      string  pretty url
 118          */
 119         function constructPrettyUrl($query){
 120                 global $_config;
 121                 $bookmark  = '';
 122
 123                 if (empty($query)){
 124                         return '';
 125                 }
 126
 127                 //Take out bookmark, and store it.
 128                 if (($pos = strpos($query, '#'))!==FALSE){
 129                         $bookmark = substr($query, $pos);
 130                         $query = substr($query, 0, $pos);
 131                 }
 132
 133                 //If this is already a pretty url,but without mod_apache rule
 134                 //unwrap it and reconstruct
 135                 if (is_array($query)){
 136                         $new_query = '';
 137                         foreach($query as $fk=>$fv){
 138                                 if      (preg_match('/\.php/', $fv)==1){
 139                                         continue;       //skip the php file
 140                                 }
 141
 142                                 //check if this is part of the rule, if so,add it, o/w ignore
 143                                 if (array_search($fv, $this->rule)!==FALSE){
 144                                         $new_query .= $fv . '=' . $query[$fk+1] . SEP;
 145                                 } elseif (preg_match('/([0-9]+)\.html/', $fv, $matches)==1){
 146                                         $new_query .= 'page=' . $matches[1] . SEP;
 147                                 }
 148                         }
 149                         $query = $new_query;    //done
 150                 }
 151
 152                 //do not change query if pretty url is disabled
 153                 if ($_config['pretty_url'] == 0){
 154                         $pretty_url = $query;
 155                 } else {
 156                         $pretty_url = '';               //init url
 157                         $query_parts = explode(SEP, $query);
 158                         foreach ($query_parts as $index=>$attributes){
 159                                 if(empty($attributes)){
 160                                         //skip the ones that are empty.
 161                                         continue;
 162                                 }
 163                                 list($key, $value) = preg_split('/\=/', $attributes, 2);
 164                                 $pretty_url .= $key . '/' . $value .'/';
 165                         }
 166                 }
 167
 168                 //finally, append bookmark if not emptied
 169                 if ($bookmark!=''){
 170                         $pretty_url .= $bookmark;
 171                 }
 172
 173                 return $pretty_url;
 174         }
 175
 176
 177         /**
 178          * This function is used to convert the input URL to a pretty URL.
 179          * @param       int             course id
 180          * @param       string  normal URL, WITHOUT the <prototal>://<host>
 181          * @return      pretty url
 182          */
 183         function convertToPrettyUrl($course_id, $url){
 184                 global $_config, $db;
 185                 $pretty_url = '';
 186
 187                 if (strpos($url, '?')!==FALSE){
 188                         list($front, $end) = preg_split('/\?/', $url);
 189                 } else {
 190                         $front = $url;
 191                         $end = '';
 192                 }
 193                 $front_array = explode('/', $front);
 194                 if ($front_array[1]=='_standard' || $front_array[1]=='_core' ){
 195                         //shift the first 2 elements.
 196                         array_shift($front_array);
 197                         array_shift($front_array);
 198                         $front = implode('/', $front_array);
 199                 }
 200                 //find out what kind of link this is, pretty url? relative url? or PHP_SELF url?
 201                 $dir_deep        = substr_count(AT_INCLUDE_PATH, '..');
 202                 $url_parts       = explode('/', $_SERVER['HTTP_HOST'] . $_SERVER['PHP_SELF']);
 203                 $host_dir        = implode('/', array_slice($url_parts, 0, count($url_parts) - $dir_deep-1));
 204                 //The link is a bounce link
 205                 if(preg_match('/bounce.php\?course=([\d]+)$/', $url, $matches)==1){
 206                         if (!empty($course_id)) {
 207                                 $pretty_url = $course_id;               //course_id should be assigned by vitals depending on the system pref.
 208                         } else {
 209                                 $pretty_url = $matches[1];              //happens when course dir name is disabled
 210                         }
 211                 } elseif(in_array(AT_PRETTY_URL_HANDLER, $front_array)===TRUE){
 212                         //The relative link is a pretty URL
 213                         $front_result = array();
 214                         //spit out the URL in between AT_PRETTY_URL_HANDLER to *.php
 215                         //note, pretty url is defined to be AT_PRETTY_URL_HANDLER/course_slug/type/location/...
 216                         //ie. AT_PRETTY_URL_HANDLER/1/forum/view.php/...
 217                         while (($needle = array_search(AT_PRETTY_URL_HANDLER, $front_array)) !== FALSE){
 218                                 $front_array = array_slice($front_array, $needle + 1);
 219                         }
 220                         $front_array = array_slice($front_array, $needle + 1);  //+2 because we want the entries after the course_slug
 221
 222                         //Handle url differently IF mod_rewrite is enabled, and if there are no query strings at the back,
 223                         //then we will have to reuse the current pathinfo to reconstruct the query.
 224                         if ($_config['apache_mod_rewrite'] > 0 && $end==''){
 225                                 $end = $front_array;    //let the class handles it
 226                         }
 227
 228                         /* Overwrite pathinfo
 229                          * ie. /go.php/1/forum/view.php/fid/1/pid/17/?fid=1&pid=17&page=5
 230                          * In the above case, cut off the original pathinfo, and replace it with the new querystrings
 231                          * If querystring is empty, then use the old one, ie. /go.php/1/forum/view.php/fid/1/pid/17/.
 232                          */
 233                         foreach($front_array as $fk=>$fv){
 234                                 array_push($front_result, $fv);
 235                                 if      (!empty($end) && preg_match('/\.php/', $fv)==1){
 236                                         break;
 237                                 }
 238                         }
 239                         $front = implode('/', $front_result);
 240                 } elseif (strpos($front, $host_dir)!==FALSE){
 241                         //Not a relative link, it contains the full PHP_SELF path.
 242                         $front = substr($front, strlen($host_dir)+1);  //stripe off the slash after the host_dir as well
 243                 } elseif ($course_id == ''){
 244                         //if this is my start page
 245                         return $url;
 246                 }
 247                 //Turn querystring to pretty URL
 248                 if ($pretty_url==''){
 249                         //Get the original course id back
 250                         $sql    = "SELECT course_id FROM ".TABLE_PREFIX."courses WHERE course_dir_name='$course_id'";
 251                         $result = mysql_query($sql, $db);
 252                         $row = mysql_fetch_assoc($result);
 253                         $course_orig = $course_id;
 254
 255                         if ($row['course_id']!=''){
 256                                 $course_orig = $row['course_id'];
 257                         }
 258
 259                         //Add course id in if both course_id or course_dir_name are not there
 260                         if (preg_match('/^\/?('.$course_id.'|'.$course_orig.')\//', $front)==0){
 261                                 $pretty_url = $course_id.'/';
 262                         }
 263
 264                         //check if there are any rules overwriting the original rules
 265                         //TODO: have a better way to do this
 266                         //              extend modularity into this.
 267                         $obj =& $this;  //default
 268                         //Overwrite the UrlRewrite obj if there are any private rules
 269                         if ($_config['apache_mod_rewrite'] > 0){
 270                                 //take out '.php' if any exists. (Apply only to non-modules, otherwise it might cause problems)
 271                                 if (preg_match('/^mods/', $front)!=1){
 272                                         if ($end=='' && preg_match('/index\.php$/', $front)==1){
 273                                                 $pretty_url .= preg_replace('/index.php/', '', $front);
 274                                         } else {
 275                                                 $pretty_url .= preg_replace('/\.php/', '', $front);
 276                                         }
 277                                 } else {
 278                                         $pretty_url .= $front;
 279                                 }
 280
 281                                 if (preg_match('/forum\/(index|view|list)\.php/', $front)==1) {
 282                                         $pretty_url = $course_id.'/forum';
 283                                         $obj = new ForumsUrl();
 284                                 } elseif (preg_match('/(content\.php)(\/cid(\/\d+))?/', $front, $matches)==1){
 285                                         $pretty_url = $course_id.'/content';
 286                                         //if there are other pretty url queries at the back, append it
 287                                         //Note: this is to fix the hopping content problem between diff courses
 288                                         if (isset($matches[3]) && $matches[3] != ''){
 289                                                 $pretty_url .= $matches[3];
 290                                         }
 291                                         $obj = new ContentUrl();
 292                                 } elseif (preg_match('/file_storage\/((index|revisions|comments)\.php)?/', $front, $matches)==1){
 293                                         $pretty_url = $course_id.'/file_storage';
 294                                         $obj = new FileStorageUrl($matches[1]);
 295                                 } elseif (preg_match('/tools\/test_intro\.php/', $front)==1){
 296                                         $pretty_url = $course_id.'/tests_surveys';
 297                                         $obj = new TestsUrl();
 298                                 } elseif (preg_match('/glossary\/index\.php/', $front)==1){
 299                                         $pretty_url = $course_id.'/glossary';
 300                                         $obj = new GlossaryUrl();
 301                                 }
 302                         } else {
 303                                 $pretty_url .= $front;
 304                         }
 305
 306                         if ($end != ''){
 307                                 //if pretty url is turned off, use '?' to separate the querystring.
 308                                 ($_config['pretty_url'] == 0)? $qs_sep = '?': $qs_sep = '/';
 309                                  $pretty_url .= $qs_sep.$obj->constructPrettyUrl($end);
 310                         }
 311                 }
 312                 //if mod_rewrite is switched on, defined in constants.inc.php
 313                 if ($_config['apache_mod_rewrite'] > 0){
 314                         return $pretty_url;
 315                 }
 316                 return AT_PRETTY_URL_HANDLER.'/'.$pretty_url;
 317         }
 318
 319
 320         /**
 321          * Return the paths where this script is
 322          */
 323         function getPath(){
 324                 //for 2.0, most of the paths are moved  into mods/_standard
 325                 //map the paths.
 326         //TODO: Add regex into the path, ie. /social/* means all folders under social.
 327         $hmap = array (
 328                     '/backups'      =>  'mods/_core',
 329                     '/content'      =>  'mods/_core',
 330                     '/enrolment'        =>      'mods/_core',
 331                     '/file_manager'     =>      'mods/_core',
 332                     '/glossary'         =>      'mods/_core',
 333                     '/groups'           =>      'mods/_core',
 334                     '/imscp'            =>      'mods/_core',
 335                     '/properties'       =>      'mods/_core',
 336                     '/announcements'=>  'mods/_standard',
 337                     '/assignments'  =>  'mods/_standard',
 338                     '/blogs'            =>      'mods/_standard',
 339                     '/chat'                     =>      'mods/_standard',
 340                     '/chat/manage'      =>      'mods/_standard',
 341                     '/course_tools'     =>      'mods/_standard',
 342                     '/directory'        =>      'mods/_standard',
 343                     '/faq'                      =>      'mods/_standard',
 344                     '/file_storage'     =>      'mods/_standard',
 345                     '/forums'       =>  'mods/_standard',
 346                     '/forums/forum'     =>      'mods/_standard',
 347                     '/google_search'=>  'mods/_standard',
 348                     '/gradebook'        =>      'mods/_standard',
 349                     '/links'            =>      'mods/_standard',
 350                     '/photos'           =>      'mods/_standard',
 351                     '/polls'            =>      'mods/_standard',
 352                     '/sitemap'          =>      'mods/_standard',
 353                     '/social'           =>      'mods/_standard',
 354                     '/social/groups'=>  'mods/_standard',
 355                     '/student_tools'=>  'mods/_standard',
 356                     '/tile_search'  =>  'mods/_standard',
 357                     '/tests'            =>      'mods/_standard',
 358                     '/tracker'          =>      'mods/_standard',
 359                     '/reading_list'     =>      'mods/_standard',
 360                     '/assignment_dropbox'       =>      'mods/_standard'
 361                                 );
 362
 363                 if ($this->path != ''){
 364                         $path = substr($this->path, 1).'/';
 365                         if (isset($hmap[$this->path])){
 366                                 $path = $hmap[$this->path].'/'.$path;
 367                         }
 368                         return $path;
 369                 }
 370                 return '';
 371         }
 372
 373         /**
 374          * Return the script name
 375          */
 376         function getFileName(){
 377                 return $this->filename;
 378         }
 379
 380         /**
 381          * Return the link of the page.
 382          */
 383         function getPage(){
 384                 return $this->getPath().$this->getFileName();
 385         }
 386
 387         /**
 388          * Return true if path, filename, and query are empty.
 389          */
 390         function isEmpty(){
 391                 return $this->isEmpty;
 392         }
 393 }
 394 ?>