include/classes/UrlRewrite/UrlRewrite.class.php

   1 <?php
   2 /************************************************************************/
   3 /* ATutor                                                                                                                               */
   4 /************************************************************************/
   5 /* Copyright (c) 2002-2008 by Greg Gay, Joel Kronenberg & Heidi Hazelton*/
   6 /* Adaptive Technology Resource Centre / University of Toronto                  */
   7 /* http://atutor.ca                                                                                                             */
   8 /*                                                                                                                                              */
   9 /* This program is free software. You can redistribute it and/or                */
  10 /* modify it under the terms of the GNU General Public License                  */
  11 /* as published by the Free Software Foundation.                                                */
  12 /************************************************************************/
  13 // $Id$
  14
  15 //Include all the classes for external rewrite rules
  16 require_once('ForumsUrl.class.php');
  17 require_once('ContentUrl.class.php');
  18 require_once('FileStorageUrl.class.php');
  19 require_once('TestsUrl.class.php');
  20 require_once('GlossaryUrl.class.php');
  21
  22 /**
  23 * UrlRewrite
  24 * Class for rewriting pretty urls.
  25 * @access       public
  26 * @author       Harris Wong
  27 * @package      UrlRewrite
  28 */
  29 class UrlRewrite  {
  30         // local variables
  31         var $path;              //the path of this script
  32         var $filename;  //script name
  33         var $query;             //the queries of the REQUEST
  34         var $isEmpty;   //true if path, filename, and query are empty
  35
  36         // constructor
  37         function UrlRewrite($path, $filename, $query) {
  38                 if ($path=='' && $filename=='' && $query==''){
  39                         $this->isEmpty = true;
  40                 } else {
  41                         $this->isEmpty = false;
  42                 }
  43                 $this->path = $path;
  44                 $this->filename = $filename;
  45                 $this->query = $query;
  46         }
  47
  48         /**
  49          * Returns the link that points to this object as a page.
  50          * @access public
  51          */
  52         function redirect(){
  53                 //redirect to that url.
  54                 return '/'.$this->getPage();
  55         }
  56
  57         /**
  58          * Parser for the pathinfo, return an array with mapped key values similar to the querystring.
  59          * @access      public
  60          * @return      array   key=>value, where keys and values have the same meaning as the ones in the query strings.
  61          */
  62         function parsePrettyQuery(){
  63                 global $_config;
  64                 $result = array();
  65
  66                 //return empty array if query is empty
  67                 if (empty($this->query)){
  68                         return $result;
  69                 }
  70
  71                 //if course_dir_name is disabled from admin.
  72                 if ($_config['pretty_url']==0){
  73                         return $this->query;
  74                 }
  75
  76                 //If the first char is /, cut it
  77                 if (strpos($this->query, '/') == 0){
  78                         $query_parts = explode('/', substr($this->query, 1));
  79                 } else {
  80                         $query_parts = explode('/', $this->query);
  81                 }
  82
  83                 //dynamically create the array
  84                 //assumption: pathinfo ALWAYS in the format of key1/value1/key2/value2/key3/value3/etc...
  85                 foreach ($query_parts as $array_index=>$key_value){
  86                         if($array_index%2 == 0 && $query_parts[$array_index]!=''){
  87                                 $result[$key_value] = $query_parts[$array_index+1];
  88                         }
  89                 }
  90                 return $result;
  91         }
  92
  93
  94         /**
  95          * Parser for the querystrings url
  96          * @access      public
  97          * @param       string  querystring
  98          * @return      array   an array of mapped keys and values like the querystrings.
  99          *
 100          * NOTE:        Stopped using this function since we've decided to dynamically create the URL.
 101          *                      See: parsePrettyQuery()
 102          */
 103         function parseQuery($query){
 104                 //return empty array if query is empty
 105                 if (empty($query)){
 106                         return array();
 107                 }
 108
 109                 parse_str($this->query, $result);
 110                 return $result;
 111         }
 112
 113
 114         /**
 115          * Construct the pretty url based on the given query.
 116          * @access      public
 117          * @param       string  the pathinfo query
 118          * @return      string  pretty url
 119          */
 120         function constructPrettyUrl($query){
 121                 global $_config;
 122                 $bookmark  = '';
 123
 124                 if (empty($query)){
 125                         return '';
 126                 }
 127
 128                 //Take out bookmark, and store it.
 129                 if (($pos = strpos($query, '#'))!==FALSE){
 130                         $bookmark = substr($query, $pos);
 131                         $query = substr($query, 0, $pos);
 132                 }
 133
 134                 //If this is already a pretty url,but without mod_apache rule
 135                 //unwrap it and reconstruct
 136                 if (is_array($query)){
 137                         $new_query = '';
 138                         foreach($query as $fk=>$fv){
 139                                 if      (preg_match('/\.php/', $fv)==1){
 140                                         continue;       //skip the php file
 141                                 }
 142
 143                                 //check if this is part of the rule, if so,add it, o/w ignore
 144                                 if (array_search($fv, $this->rule)!==FALSE){
 145                                         $new_query .= $fv . '=' . $query[$fk+1] . SEP;
 146                                 } elseif (preg_match('/([0-9]+)\.html/', $fv, $matches)==1){
 147                                         $new_query .= 'page=' . $matches[1] . SEP;
 148                                 }
 149                         }
 150                         $query = $new_query;    //done
 151                 }
 152
 153                 //do not change query if pretty url is disabled
 154                 if ($_config['pretty_url'] == 0){
 155                         $pretty_url = $query;
 156                 } else {
 157                         $pretty_url = '';               //init url
 158                         $query_parts = explode(SEP, $query);
 159                         foreach ($query_parts as $index=>$attributes){
 160                                 if(empty($attributes)){
 161                                         //skip the ones that are empty.
 162                                         continue;
 163                                 }
 164                                 list($key, $value) = preg_split('/\=/', $attributes, 2);
 165                                 $pretty_url .= $key . '/' . $value .'/';
 166                         }
 167                 }
 168
 169                 //finally, append bookmark if not emptied
 170                 if ($bookmark!=''){
 171                         $pretty_url .= $bookmark;
 172                 }
 173
 174                 return $pretty_url;
 175         }
 176
 177
 178         /**
 179          * This function is used to convert the input URL to a pretty URL.
 180          * @param       int             course id
 181          * @param       string  normal URL, WITHOUT the <prototal>://<host>
 182          * @return      pretty url
 183          */
 184         function convertToPrettyUrl($course_id, $url){
 185                 global $_config, $db;
 186                 $pretty_url = '';
 187
 188                 if (strpos($url, '?')!==FALSE){
 189                         list($front, $end) = preg_split('/\?/', $url);
 190                 } else {
 191                         $front = $url;
 192                         $end = '';
 193                 }
 194
 195                 $front_array = explode('/', $front);
 196
 197                 //find out what kind of link this is, pretty url? relative url? or PHP_SELF url?
 198                 $dir_deep        = substr_count(AT_INCLUDE_PATH, '..');
 199                 $url_parts       = explode('/', $_SERVER['HTTP_HOST'] . $_SERVER['PHP_SELF']);
 200                 $host_dir        = implode('/', array_slice($url_parts, 0, count($url_parts) - $dir_deep-1));
 201                 //The link is a bounce link
 202                 if(preg_match('/bounce.php\?course=([\d]+)$/', $url, $matches)==1){
 203                         if (!empty($course_id)) {
 204                                 $pretty_url = $course_id;               //course_id should be assigned by vitals depending on the system pref.
 205                         } else {
 206                                 $pretty_url = $matches[1];              //happens when course dir name is disabled
 207                         }
 208                 } elseif(in_array(AT_PRETTY_URL_HANDLER, $front_array)===TRUE){
 209                         //The relative link is a pretty URL
 210                         $front_result = array();
 211                         //spit out the URL in between AT_PRETTY_URL_HANDLER to *.php
 212                         //note, pretty url is defined to be AT_PRETTY_URL_HANDLER/course_slug/type/location/...
 213                         //ie. AT_PRETTY_URL_HANDLER/1/forum/view.php/...
 214                         while (($needle = array_search(AT_PRETTY_URL_HANDLER, $front_array)) !== FALSE){
 215                                 $front_array = array_slice($front_array, $needle + 1);
 216                         }
 217                         $front_array = array_slice($front_array, $needle + 1);  //+2 because we want the entries after the course_slug
 218
 219                         //Handle url differently IF mod_rewrite is enabled, and if there are no query strings at the back,
 220                         //then we will have to reuse the current pathinfo to reconstruct the query.
 221                         if ($_config['apache_mod_rewrite'] > 0 && $end==''){
 222                                 $end = $front_array;    //let the class handles it
 223                         }
 224
 225                         /* Overwrite pathinfo
 226                          * ie. /go.php/1/forum/view.php/fid/1/pid/17/?fid=1&pid=17&page=5
 227                          * In the above case, cut off the original pathinfo, and replace it with the new querystrings
 228                          * If querystring is empty, then use the old one, ie. /go.php/1/forum/view.php/fid/1/pid/17/.
 229                          */
 230                         foreach($front_array as $fk=>$fv){
 231                                 array_push($front_result, $fv);
 232                                 if      (!empty($end) && preg_match('/\.php/', $fv)==1){
 233                                         break;
 234                                 }
 235                         }
 236                         $front = implode('/', $front_result);
 237                 } elseif (strpos($front, $host_dir)!==FALSE){
 238                         //Not a relative link, it contains the full PHP_SELF path.
 239                         $front = substr($front, strlen($host_dir)+1);  //stripe off the slash after the host_dir as well
 240                 } elseif ($course_id == ''){
 241                         //if this is my start page
 242                         return $url;
 243                 }
 244                 //Turn querystring to pretty URL
 245                 if ($pretty_url==''){
 246                         //Get the original course id back
 247                         $sql    = "SELECT course_id FROM ".TABLE_PREFIX."courses WHERE course_dir_name='$course_id'";
 248                         $result = mysql_query($sql, $db);
 249                         $row = mysql_fetch_assoc($result);
 250                         $course_orig = $course_id;
 251
 252                         if ($row['course_id']!=''){
 253                                 $course_orig = $row['course_id'];
 254                         }
 255
 256                         //Add course id in if both course_id or course_dir_name are not there
 257                         if (preg_match('/^\/?('.$course_id.'|'.$course_orig.')\//', $front)==0){
 258                                 $pretty_url = $course_id.'/';
 259                         }
 260
 261                         //check if there are any rules overwriting the original rules
 262                         //TODO: have a better way to do this
 263                         //              extend modularity into this.
 264                         $obj =& $this;  //default
 265                         //Overwrite the UrlRewrite obj if there are any private rules
 266                         if ($_config['apache_mod_rewrite'] > 0){
 267                                 //take out '.php' if any exists. (Apply only to non-modules, otherwise it might cause problems)
 268                                 if (preg_match('/^mods/', $front)!=1){
 269                                         if ($end=='' && preg_match('/index\.php$/', $front)==1){
 270                                                 $pretty_url .= preg_replace('/index.php/', '', $front);
 271                                         } else {
 272                                                 $pretty_url .= preg_replace('/\.php/', '', $front);
 273                                         }
 274                                 } else {
 275                                         $pretty_url .= $front;
 276                                 }
 277
 278                                 if (preg_match('/forum\/(index|view|list)\.php/', $front)==1) {
 279                                         $pretty_url = $course_id.'/forum';
 280                                         $obj = new ForumsUrl();
 281                                 } elseif (preg_match('/(content\.php)(\/cid(\/\d+))?/', $front, $matches)==1){
 282                                         $pretty_url = $course_id.'/content';
 283                                         //if there are other pretty url queries at the back, append it
 284                                         //Note: this is to fix the hopping content problem between diff courses
 285                                         if (isset($matches[3]) && $matches[3] != ''){
 286                                                 $pretty_url .= $matches[3];
 287                                         }
 288                                         $obj = new ContentUrl();
 289                                 } elseif (preg_match('/file_storage\/((index|revisions|comments)\.php)?/', $front, $matches)==1){
 290                                         $pretty_url = $course_id.'/file_storage';
 291                                         $obj = new FileStorageUrl($matches[1]);
 292                                 } elseif (preg_match('/tools\/test_intro\.php/', $front)==1){
 293                                         $pretty_url = $course_id.'/tests_surveys';
 294                                         $obj = new TestsUrl();
 295                                 } elseif (preg_match('/glossary\/index\.php/', $front)==1){
 296                                         $pretty_url = $course_id.'/glossary';
 297                                         $obj = new GlossaryUrl();
 298                                 }
 299                         } else {
 300                                 $pretty_url .= $front;
 301                         }
 302
 303                         if ($end != ''){
 304                                 //if pretty url is turned off, use '?' to separate the querystring.
 305                                 ($_config['pretty_url'] == 0)? $qs_sep = '?': $qs_sep = '/';
 306                                  $pretty_url .= $qs_sep.$obj->constructPrettyUrl($end);
 307                         }
 308                 }
 309
 310                 //if mod_rewrite is switched on, defined in constants.inc.php
 311                 if ($_config['apache_mod_rewrite'] > 0){
 312                         return $pretty_url;
 313                 }
 314                 return AT_PRETTY_URL_HANDLER.'/'.$pretty_url;
 315         }
 316
 317
 318         /**
 319          * Return the paths where this script is
 320          */
 321         function getPath(){
 322                 if ($this->path != ''){
 323                         return substr($this->path, 1).'/';
 324                 }
 325                 return '';
 326         }
 327
 328         /**
 329          * Return the script name
 330          */
 331         function getFileName(){
 332                 return $this->filename;
 333         }
 334
 335         /**
 336          *
 337          */
 338         function getPage(){
 339                 return $this->getPath().$this->getFileName();
 340         }
 341
 342         /**
 343          * Return true if path, filename, and query are empty.
 344          */
 345         function isEmpty(){
 346                 return $this->isEmpty;
 347         }
 348 }
 349 ?>