[Sommaire] [Imprimer]

   1  <?php
   2  /**
   3   * DokuWiki fulltextsearch functions using the index
   4   *
   5   * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
   6   * @author     Andreas Gohr <andi@splitbrain.org>
   7   */
   8  
   9    if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../').'/');
  10    require_once (DOKU_INC.'inc/indexer.php');
  11  
  12  
  13  /**
  14   * The fulltext search
  15   *
  16   * Returns a list of matching documents for the given query
  17   *
  18   */
  19  function ft_pageSearch($query,&$poswords){
  20      $q = ft_queryParser($query);
  21      // use this for higlighting later:
  22      $poswords = str_replace('*','',join(' ',$q['and']));
  23  
  24      // lookup all words found in the query
  25      $words  = array_merge($q['and'],$q['not']);
  26      if(!count($words)) return array();
  27      $result = idx_lookup($words);
  28  
  29      // merge search results with query
  30      foreach($q['and'] as $pos => $w){
  31          $q['and'][$pos] = $result[$w];
  32      }
  33      // create a list of unwanted docs
  34      $not = array();
  35      foreach($q['not'] as $pos => $w){
  36          $not = array_merge($not,array_keys($result[$w]));
  37      }
  38  
  39      // combine and-words
  40      if(count($q['and']) > 1){
  41          $docs = ft_resultCombine($q['and']);
  42      }else{
  43          $docs = $q['and'][0];
  44      }
  45      if(!count($docs)) return array();
  46  
  47      // create a list of hidden pages in the result
  48      $hidden = array();
  49      $hidden = array_filter(array_keys($docs),'isHiddenPage');
  50      $not = array_merge($not,$hidden);
  51  
  52      // filter unmatched namespaces
  53      if(!empty($q['ns'])) {
  54          $pattern = implode('|^',$q['ns']);
  55          foreach($docs as $key => $val) {
  56              if(!preg_match('/^'.$pattern.'/',$key)) {
  57                  unset($docs[$key]);
  58              }
  59          }
  60      }
  61  
  62      // remove negative matches
  63      foreach($not as $n){
  64          unset($docs[$n]);
  65      }
  66  
  67      if(!count($docs)) return array();
  68      // handle phrases
  69      if(count($q['phrases'])){
  70          //build a regexp
  71          $q['phrases'] = array_map('utf8_strtolower',$q['phrases']);
  72          $q['phrases'] = array_map('preg_quote',$q['phrases']);
  73          $regex = '('.join('|',$q['phrases']).')';
  74          // check the source of all documents for the exact phrases
  75          foreach(array_keys($docs) as $id){
  76              $text  = utf8_strtolower(rawWiki($id));
  77              if(!preg_match('/'.$regex.'/usi',$text)){
  78                  unset($docs[$id]); // no hit - remove
  79              }
  80          }
  81      }
  82  
  83      if(!count($docs)) return array();
  84  
  85      // check ACL permissions
  86      foreach(array_keys($docs) as $doc){
  87          if(auth_quickaclcheck($doc) < AUTH_READ){
  88              unset($docs[$doc]);
  89          }
  90      }
  91  
  92      if(!count($docs)) return array();
  93  
  94      // if there are any hits left, sort them by count
  95      arsort($docs);
  96  
  97      return $docs;
  98  }
  99  
 100  /**
 101   * Returns the backlinks for a given page
 102   *
 103   * Does a quick lookup with the fulltext index, then
 104   * evaluates the instructions of the found pages
 105   */
 106  function ft_backlinks($id){
 107      global $conf;
 108      $swfile   = DOKU_INC.'inc/lang/'.$conf['lang'].'/stopwords.txt';
 109      $stopwords = @file_exists($swfile) ? file($swfile) : array();
 110  
 111      $result = array();
 112  
 113      // quick lookup of the pagename
 114      $page    = noNS($id);
 115      $matches = idx_lookup(idx_tokenizer($page,$stopwords));  // pagename may contain specials (_ or .)
 116      $docs    = array_keys(ft_resultCombine(array_values($matches)));
 117      $docs    = array_filter($docs,'isVisiblePage'); // discard hidden pages
 118      if(!count($docs)) return $result;
 119      require_once (DOKU_INC.'inc/parserutils.php');
 120  
 121      // check metadata for matching links
 122      foreach($docs as $match){
 123          // metadata relation reference links are already resolved
 124          $links = p_get_metadata($match,'relation references');
 125          if (isset($links[$id])) $result[] = $match;
 126      }
 127  
 128      if(!count($result)) return $result;
 129  
 130      // check ACL permissions
 131      foreach(array_keys($result) as $idx){
 132          if(auth_quickaclcheck($result[$idx]) < AUTH_READ){
 133              unset($result[$idx]);
 134          }
 135      }
 136  
 137      sort($result);
 138      return $result;
 139  }
 140  
 141  /**
 142   * Quicksearch for pagenames
 143   *
 144   * By default it only matches the pagename and ignores the
 145   * namespace. This can be changed with the second parameter
 146   *
 147   * @author Andreas Gohr <andi@splitbrain.org>
 148   */
 149  function ft_pageLookup($id,$pageonly=true){
 150      global $conf;
 151      $id    = preg_quote($id,'/');
 152      $pages = file($conf['cachedir'].'/page.idx');
 153      $pages = array_values(preg_grep('/'.$id.'/',$pages));
 154  
 155      $cnt = count($pages);
 156      for($i=0; $i<$cnt; $i++){
 157          if($pageonly){
 158              if(!preg_match('/'.$id.'/',noNS($pages[$i]))){
 159                  unset($pages[$i]);
 160                  continue;
 161              }
 162          }
 163          if(!@file_exists(wikiFN($pages[$i]))){
 164              unset($pages[$i]);
 165              continue;
 166          }
 167      }
 168  
 169      $pages = array_filter($pages,'isVisiblePage'); // discard hidden pages
 170      if(!count($pages)) return array();
 171  
 172      // check ACL permissions
 173      foreach(array_keys($pages) as $idx){
 174          if(auth_quickaclcheck($pages[$idx]) < AUTH_READ){
 175              unset($pages[$idx]);
 176          }
 177      }
 178  
 179      sort($pages);
 180      return $pages;
 181  }
 182  
 183  /**
 184   * Creates a snippet extract
 185   *
 186   * @author Andreas Gohr <andi@splitbrain.org>
 187   */
 188  function ft_snippet($id,$poswords){
 189      $poswords = preg_quote($poswords,'#');
 190      $re       = '('.str_replace(' ','|',$poswords).')';
 191      $text     = rawWiki($id);
 192  
 193      $match = array();
 194      $snippets = array();
 195      $utf8_offset = $offset = $end = 0;
 196      $len = utf8_strlen($text);
 197  
 198      for ($cnt=3; $cnt--;) {
 199        if (!preg_match('#'.$re.'#iu',$text,$match,PREG_OFFSET_CAPTURE,$offset)) break;
 200  
 201        list($str,$idx) = $match[0];
 202  
 203        // convert $idx (a byte offset) into a utf8 character offset
 204        $utf8_idx = utf8_strlen(substr($text,0,$idx));
 205        $utf8_len = utf8_strlen($str);
 206  
 207        // establish context, 100 bytes surrounding the match string
 208        // first look to see if we can go 100 either side,
 209        // then drop to 50 adding any excess if the other side can't go to 50,
 210        $pre = min($utf8_idx-$utf8_offset,100);
 211        $post = min($len-$utf8_idx-$utf8_len,100);
 212  
 213        if ($pre>50 && $post>50) {
 214          $pre = $post = 50;
 215        } else if ($pre>50) {
 216          $pre = min($pre,100-$post);
 217        } else if ($post>50) {
 218          $post = min($post, 100-$pre);
 219        } else {
 220          // both are less than 50, means the context is the whole string
 221          // make it so and break out of this loop - there is no need for the
 222          // complex snippet calculations
 223          $snippets = array($text);
 224          break;
 225        }
 226  
 227        // establish context start and end points, try to append to previous
 228        // context if possible
 229        $start = $utf8_idx - $pre;
 230        $append = ($start < $end) ? $end : false;  // still the end of the previous context snippet
 231        $end = $utf8_idx + $utf8_len + $post;      // now set it to the end of this context
 232  
 233        if ($append) {
 234          $snippets[count($snippets)-1] .= utf8_substr($text,$append,$end-$append);
 235        } else {
 236          $snippets[] = utf8_substr($text,$start,$end-$start);
 237        }
 238  
 239        // set $offset for next match attempt
 240        //   substract strlen to avoid splitting a potential search success,
 241        //   this is an approximation as the search pattern may match strings
 242        //   of varying length and it will fail if the context snippet
 243        //   boundary breaks a matching string longer than the current match
 244        $utf8_offset = $utf8_idx + $post;
 245        $offset = $idx + strlen(utf8_substr($text,$utf8_idx,$post));
 246        $offset = utf8_correctIdx($text,$offset);
 247      }
 248  
 249      $m = "\1";
 250      $snippets = preg_replace('#'.$re.'#iu',$m.'$1'.$m,$snippets);
 251      $snippet = preg_replace('#'.$m.'([^'.$m.']*?)'.$m.'#iu','<span class="search_hit">$1</span>',hsc(join('... ',$snippets)));
 252  
 253      return $snippet;
 254  }
 255  
 256  /**
 257   * Combine found documents and sum up their scores
 258   *
 259   * This function is used to combine searched words with a logical
 260   * AND. Only documents available in all arrays are returned.
 261   *
 262   * based upon PEAR's PHP_Compat function for array_intersect_key()
 263   *
 264   * @param array $args An array of page arrays
 265   */
 266  function ft_resultCombine($args){
 267      $array_count = count($args);
 268      if($array_count == 1){
 269          return $args[0];
 270      }
 271  
 272      $result = array();
 273      foreach ($args[0] as $key1 => $value1) {
 274          for ($i = 1; $i !== $array_count; $i++) {
 275              foreach ($args[$i] as $key2 => $value2) {
 276                  if ((string) $key1 === (string) $key2) {
 277                      if(!isset($result[$key1])) $result[$key1] = $value1;
 278                      $result[$key1] += $value2;
 279                  }
 280              }
 281          }
 282      }
 283      return $result;
 284  }
 285  
 286  /**
 287   * Builds an array of search words from a query
 288   *
 289   * @todo support OR and parenthesises?
 290   */
 291  function ft_queryParser($query){
 292      global $conf;
 293      $swfile   = DOKU_INC.'inc/lang/'.$conf['lang'].'/stopwords.txt';
 294      if(@file_exists($swfile)){
 295          $stopwords = file($swfile);
 296      }else{
 297          $stopwords = array();
 298      }
 299  
 300      $q = array();
 301      $q['query']   = $query;
 302      $q['ns']      = array();
 303      $q['phrases'] = array();
 304      $q['and']     = array();
 305      $q['not']     = array();
 306  
 307      // strip namespace from query
 308      if(preg_match('/([^@]*)@(.*)/',$query,$match))  {
 309          $query = $match[1];
 310          $q['ns'] = explode('@',preg_replace("/ /",'',$match[2]));
 311      }
 312  
 313      // handle phrase searches
 314      while(preg_match('/"(.*?)"/',$query,$match)){
 315          $q['phrases'][] = $match[1];
 316          $q['and'] = array_merge(idx_tokenizer($match[0],$stopwords));
 317          $query = preg_replace('/"(.*?)"/','',$query,1);
 318      }
 319  
 320      $words = explode(' ',$query);
 321      foreach($words as $w){
 322          if($w{0} == '-'){
 323              $token = idx_tokenizer($w,$stopwords,true);
 324              if(count($token)) $q['not'] = array_merge($q['not'],$token);
 325          }else{
 326              // asian "words" need to be searched as phrases
 327              if(@preg_match_all('/('.IDX_ASIAN.'+)/u',$w,$matches)){
 328                  $q['phrases'] = array_merge($q['phrases'],$matches[1]);
 329  
 330              }
 331              $token = idx_tokenizer($w,$stopwords,true);
 332              if(count($token)) $q['and'] = array_merge($q['and'],$token);
 333          }
 334      }
 335  
 336      return $q;
 337  }
 338  
 339  //Setup VIM: ex: et ts=4 enc=utf-8 :