search.module 28.1 KB
Newer Older
Dries's avatar
 
Dries committed
1
<?php
2
// $Id$
Dries's avatar
 
Dries committed
3

Dries's avatar
 
Dries committed
4 5 6 7 8
/**
 * @file
 * Enables site-wide keyword searching.
 */

9
/**
10
 * Matches Unicode character classes to exclude from the search index.
Steven Wittens's avatar
Steven Wittens committed
11
 *
12 13
 * See: http://www.unicode.org/Public/UNIDATA/UCD.html#General_Category_Values
 *
14
 * The index only contains the following character classes:
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
 * Lu     Letter, Uppercase
 * Ll     Letter, Lowercase
 * Lt     Letter, Titlecase
 * Lm     Letter, Modifier
 * Lo     Letter, Other
 * Mn     Mark, Nonspacing
 * Mc     Mark, Spacing Combining
 * Nd     Number, Decimal Digit
 * Nl     Number, Letter
 * No     Number, Other
 * Sm     Symbol, Math
 * Sc     Symbol, Currency
 * Sk     Symbol, Modifier
 * So     Symbol, Other
 *
30
 * All character classes not in the list above (enclosing marks, punctuation, control codes and spacers):
31 32 33 34 35
 * 'Me', 'Pc', 'Pd', 'Ps', 'Pe', 'Pi', 'Pf', 'Po', 'Zs', 'Zl', 'Zp', 'Cc', 'Cf', 'Cs', 'Co'
 */
define('PREG_CLASS_SEARCH_EXCLUDE', '\x{0}-\x{23}\x{25}-\x{2a}\x{2c}-\x{2f}\x{3a}\x{3b}\x{3f}\x{40}\x{5b}-\x{5d}\x{5f}\x{7b}\x{7d}\x{7f}-\x{a1}\x{ab}\x{ad}\x{b7}\x{bb}\x{bf}\x{37e}\x{387}\x{488}\x{489}\x{55a}-\x{55f}\x{589}\x{58a}\x{5be}\x{5c0}\x{5c3}\x{5f3}\x{5f4}\x{600}-\x{603}\x{60c}\x{60d}\x{61b}\x{61f}\x{66a}-\x{66d}\x{6d4}\x{6dd}\x{6de}\x{700}-\x{70d}\x{70f}\x{964}\x{965}\x{970}\x{df4}\x{e4f}\x{e5a}\x{e5b}\x{f04}-\x{f12}\x{f3a}-\x{f3d}\x{f85}\x{104a}-\x{104f}\x{10fb}\x{1361}-\x{1368}\x{166d}\x{166e}\x{1680}\x{169b}\x{169c}\x{16eb}-\x{16ed}\x{1735}\x{1736}\x{17b4}\x{17b5}\x{17d4}-\x{17d6}\x{17d8}-\x{17da}\x{1800}-\x{180a}\x{180e}\x{1944}\x{1945}\x{2000}-\x{2043}\x{2045}-\x{2051}\x{2053}\x{2054}\x{2057}\x{205f}-\x{2063}\x{206a}-\x{206f}\x{207d}\x{207e}\x{208d}\x{208e}\x{20dd}-\x{20e0}\x{20e2}-\x{20e4}\x{2329}\x{232a}\x{23b4}-\x{23b6}\x{2768}-\x{2775}\x{27e6}-\x{27eb}\x{2983}-\x{2998}\x{29d8}-\x{29db}\x{29fc}\x{29fd}\x{3000}-\x{3003}\x{3008}-\x{3011}\x{3014}-\x{301f}\x{3030}\x{303d}\x{30a0}\x{30fb}\x{d800}\x{db7f}\x{db80}\x{dbff}\x{dc00}\x{dfff}\x{e000}\x{f8ff}\x{fd3e}\x{fd3f}\x{fe30}-\x{fe52}\x{fe54}-\x{fe61}\x{fe63}\x{fe68}\x{fe6a}\x{fe6b}\x{feff}\x{ff01}-\x{ff03}\x{ff05}-\x{ff0a}\x{ff0c}-\x{ff0f}\x{ff1a}\x{ff1b}\x{ff1f}\x{ff20}\x{ff3b}-\x{ff3d}\x{ff3f}\x{ff5b}\x{ff5d}\x{ff5f}-\x{ff65}\x{fff9}-\x{fffb}\x{10100}\x{10101}\x{1039f}\x{1d173}-\x{1d17a}\x{e0001}\x{e0020}-\x{e007f}\x{f0000}\x{ffffd}\x{100000}');

/**
Steven Wittens's avatar
Steven Wittens committed
36
 * Matches all 'N' Unicode character classes (numbers)
37 38 39 40
 */
define('PREG_CLASS_NUMBERS', '\x{30}-\x{39}\x{b2}\x{b3}\x{b9}\x{bc}-\x{be}\x{660}-\x{669}\x{6f0}-\x{6f9}\x{966}-\x{96f}\x{9e6}-\x{9ef}\x{9f4}-\x{9f9}\x{a66}-\x{a6f}\x{ae6}-\x{aef}\x{b66}-\x{b6f}\x{be7}-\x{bf2}\x{c66}-\x{c6f}\x{ce6}-\x{cef}\x{d66}-\x{d6f}\x{e50}-\x{e59}\x{ed0}-\x{ed9}\x{f20}-\x{f33}\x{1040}-\x{1049}\x{1369}-\x{137c}\x{16ee}-\x{16f0}\x{17e0}-\x{17e9}\x{17f0}-\x{17f9}\x{1810}-\x{1819}\x{1946}-\x{194f}\x{2070}\x{2074}-\x{2079}\x{2080}-\x{2089}\x{2153}-\x{2183}\x{2460}-\x{249b}\x{24ea}-\x{24ff}\x{2776}-\x{2793}\x{3007}\x{3021}-\x{3029}\x{3038}-\x{303a}\x{3192}-\x{3195}\x{3220}-\x{3229}\x{3251}-\x{325f}\x{3280}-\x{3289}\x{32b1}-\x{32bf}\x{ff10}-\x{ff19}\x{10107}-\x{10133}\x{10320}-\x{10323}\x{1034a}\x{104a0}-\x{104a9}\x{1d7ce}-\x{1d7ff}');

/**
Steven Wittens's avatar
Steven Wittens committed
41
 * Matches all 'P' Unicode character classes (punctuation)
42 43 44
 */
define('PREG_CLASS_PUNCTUATION', '\x{21}-\x{23}\x{25}-\x{2a}\x{2c}-\x{2f}\x{3a}\x{3b}\x{3f}\x{40}\x{5b}-\x{5d}\x{5f}\x{7b}\x{7d}\x{a1}\x{ab}\x{b7}\x{bb}\x{bf}\x{37e}\x{387}\x{55a}-\x{55f}\x{589}\x{58a}\x{5be}\x{5c0}\x{5c3}\x{5f3}\x{5f4}\x{60c}\x{60d}\x{61b}\x{61f}\x{66a}-\x{66d}\x{6d4}\x{700}-\x{70d}\x{964}\x{965}\x{970}\x{df4}\x{e4f}\x{e5a}\x{e5b}\x{f04}-\x{f12}\x{f3a}-\x{f3d}\x{f85}\x{104a}-\x{104f}\x{10fb}\x{1361}-\x{1368}\x{166d}\x{166e}\x{169b}\x{169c}\x{16eb}-\x{16ed}\x{1735}\x{1736}\x{17d4}-\x{17d6}\x{17d8}-\x{17da}\x{1800}-\x{180a}\x{1944}\x{1945}\x{2010}-\x{2027}\x{2030}-\x{2043}\x{2045}-\x{2051}\x{2053}\x{2054}\x{2057}\x{207d}\x{207e}\x{208d}\x{208e}\x{2329}\x{232a}\x{23b4}-\x{23b6}\x{2768}-\x{2775}\x{27e6}-\x{27eb}\x{2983}-\x{2998}\x{29d8}-\x{29db}\x{29fc}\x{29fd}\x{3001}-\x{3003}\x{3008}-\x{3011}\x{3014}-\x{301f}\x{3030}\x{303d}\x{30a0}\x{30fb}\x{fd3e}\x{fd3f}\x{fe30}-\x{fe52}\x{fe54}-\x{fe61}\x{fe63}\x{fe68}\x{fe6a}\x{fe6b}\x{ff01}-\x{ff03}\x{ff05}-\x{ff0a}\x{ff0c}-\x{ff0f}\x{ff1a}\x{ff1b}\x{ff1f}\x{ff20}\x{ff3b}-\x{ff3d}\x{ff3f}\x{ff5b}\x{ff5d}\x{ff5f}-\x{ff65}\x{10100}\x{10101}\x{1039f}');

Dries's avatar
 
Dries committed
45 46 47 48
/**
 * Implementation of hook_help().
 */
function search_help($section = 'admin/help#search') {
Dries's avatar
 
Dries committed
49
  switch ($section) {
Dries's avatar
 
Dries committed
50 51
    case 'admin/modules#description':
      return t('Enables site-wide keyword searching.');
52 53
    case 'admin/settings/search':
      return t('
Steven Wittens's avatar
Steven Wittens committed
54
<p>The search engine works by maintaining an index of the words in your site\'s content. You can adjust the settings below to tweak the indexing behaviour. Note that the search requires cron to be set up correctly.</p>
55
');
56 57 58 59 60 61
    case 'search#noresults':
      return t('<p><ul>
<li>Check if your spelling is correct.</li>
<li>Try using wildcards: <em>walk*</em> matches <em>walker</em>, <em>walking</em>, ...</li>
<li>Use longer words (words shorter than %number letters are ignored).</li>
</ul></p>', array('%number' => variable_get('minimum_word_size', 3)));
Dries's avatar
 
Dries committed
62
  }
Dries's avatar
 
Dries committed
63
}
Kjartan's avatar
Kjartan committed
64 65

/**
Dries's avatar
 
Dries committed
66
 * Implementation of hook_perm().
Kjartan's avatar
Kjartan committed
67
 */
Dries's avatar
 
Dries committed
68
function search_perm() {
Dries's avatar
 
Dries committed
69
  return array('search content', 'administer search');
Dries's avatar
 
Dries committed
70 71
}

Dries's avatar
 
Dries committed
72 73 74
/**
 * Implementation of hook_menu().
 */
Dries's avatar
 
Dries committed
75
function search_menu($may_cache) {
Dries's avatar
 
Dries committed
76
  $items = array();
Dries's avatar
 
Dries committed
77 78

  if ($may_cache) {
Dries's avatar
Dries committed
79
    $items[] = array('path' => 'search', 'title' => t('search'),
Dries's avatar
 
Dries committed
80 81 82
      'callback' => 'search_view',
      'access' => user_access('search content'),
      'type' => MENU_SUGGESTED_ITEM);
Dries's avatar
Dries committed
83 84 85 86 87 88 89 90 91 92

    foreach (module_list() as $name) {
      if (module_hook($name, 'search')) {
        $items[] = array('path' => 'search/'. $name, 'title' => module_invoke($name, 'search', 'name'),
          'callback' => 'search_view',
          'access' => user_access('search content'),
          'type' => $name == 'node' ? MENU_DEFAULT_LOCAL_TASK : MENU_LOCAL_TASK);
      }
    }

Dries's avatar
Dries committed
93
    $items[] = array('path' => 'admin/settings/search', 'title' => t('search'),
94
      'callback' => 'search_admin',
95
      'type' => MENU_NORMAL_ITEM,
96
      'access' => user_access('administer site configuration'));
Dries's avatar
 
Dries committed
97 98
  }

Dries's avatar
 
Dries committed
99 100 101 102 103 104
  return $items;
}

/**
 * Menu callback; displays the search module settings page.
 */
105
function search_admin() {
Dries's avatar
 
Dries committed
106
  if ($_POST) {
Dries's avatar
Dries committed
107
    if (variable_get('minimum_word_size', 3) != $_POST['edit']['minimum_word_size'] ||
108 109 110 111 112 113 114 115 116
        variable_get('remove_short', 3) != $_POST['edit']['remove_short']) {
      // Note: ensure logical order of messages
      system_settings_save();
      drupal_set_message(t('The index will be rebuilt.'));
      search_wipe();
    }
    else {
      system_settings_save();
    }
Dries's avatar
Dries committed
117
  }
Dries's avatar
 
Dries committed
118

119 120 121 122 123 124 125 126 127
  // Collect some stats
  $remaining = 0;
  $total = 0;
  foreach (module_list() as $module) {
    if (module_hook($module, 'search')) {
      $status = module_invoke($module, 'search', 'status');
      $remaining += $status['remaining'];
      $total += $status['total'];
    }
Dries's avatar
Dries committed
128
  }
129 130 131 132 133 134 135 136
  $percentage = ((int)min(100, 100 * ($total - $remaining) / max(1, $total))) . '%';
  $status = '<p><strong>'. t('%percentage of the site has been indexed. There are %count items left to index.', array('%percentage' => $percentage, '%count' => $remaining)) .'</strong></p>';
  $output = form_group('Indexing status', $status);

  // Indexing throttle:
  $items = drupal_map_assoc(array(10, 20, 50, 100, 200, 500));
  $group = form_select(t('Items to index per cron run'), 'search_cron_limit', variable_get('search_cron_limit', 100), $items, t('The maximum amount of items that will be indexed in one cron run. Set this number lower if your cron is timing out or if PHP is running out of memory.'));
  $output .= form_group(t('Indexing throttle'), $group);
Dries's avatar
 
Dries committed
137
  // Indexing settings:
138 139
  $group = '<em>'. t('<p>Changing the settings below will cause the site index to be rebuilt. The search index is not cleared but systematically updated to reflect the new settings. Searching will continue to work but new content won\'t be indexed until all existing content has been re-indexed.</p><p>The default settings should be appropriate for the majority of sites.</p>') .'</em>';
  $group .= form_textfield(t('Minimum word length to index'), 'minimum_word_size', variable_get('minimum_word_size', 3), 3, 3, t('The number of characters a word has to be to be indexed. Words shorter than this will not be searchable.'));
140
  $group .= form_textfield(t('Minimum word length to search for'), 'remove_short', variable_get('remove_short', 3), 3, 3, t('The number of characters a word has to be to be searched for, including wildcard characters.'));
141
  $output .= form_group(t('Indexing settings'), $group);
Dries's avatar
 
Dries committed
142

Dries's avatar
 
Dries committed
143
  print theme('page', system_settings_form($output));
Dries's avatar
 
Dries committed
144 145
}

Dries's avatar
Dries committed
146
/**
147 148 149 150 151 152 153
 * Wipes a part of or the entire search index.
 *
 * @param $sid
 *  (optional) The SID of the item to wipe. If specified, $type must be passed
 *  too.
 * @param $type
 *  (optional) The type of item to wipe.
Dries's avatar
Dries committed
154
 */
155
function search_wipe($sid = NULL, $type = NULL) {
156 157 158 159 160 161 162
  if ($type == NULL && $sid == NULL) {
    module_invoke_all('search', 'reset');
  }
  else {
    db_query("DELETE FROM {search_index} WHERE sid = %d AND type = '%s'", $sid, $type);
    db_query("DELETE FROM {search_index} WHERE fromsid = %d AND fromtype = '%s'", $sid, $type);
  }
Dries's avatar
Dries committed
163 164
}

165 166 167 168 169 170 171 172 173 174 175 176 177 178 179
/**
 * Marks a word as dirty (or retrieves the list of dirty words). This is used
 * during indexing (cron). Words which are dirty have outdated total counts in
 * the search_total table, and need to be recounted.
 */
function search_dirty($word = null) {
  static $dirty = array();
  if ($word !== null) {
    $dirty[$word] = true;
  }
  else {
    return $dirty;
  }
}

Kjartan's avatar
Kjartan committed
180
/**
Dries's avatar
 
Dries committed
181 182
 * Implementation of hook_cron().
 *
183 184
 * Fires hook_update_index() in all modules and cleans up dirty words (see
 * search_dirty).
Kjartan's avatar
Kjartan committed
185 186
 */
function search_cron() {
Dries's avatar
Dries committed
187
  // Update word index
Kjartan's avatar
Kjartan committed
188
  foreach (module_list() as $module) {
189 190
    module_invoke($module, 'update_index');
  }
Dries's avatar
Dries committed
191
  // Update word counts for new/changed words
192 193
  foreach (search_dirty() as $word => $dummy) {
    $total = db_result(db_query("SELECT SUM(score) FROM {search_index} WHERE word = '%s'", $word));
Dries's avatar
Dries committed
194 195
    db_query("UPDATE {search_total} SET count = %d WHERE word = '%s'", $total, $word);
    if (!db_affected_rows()) {
196 197 198 199 200
      // Note: affected rows does not count matching rows that already had the right value!
      $exists = db_result(db_query("SELECT COUNT(*) FROM {search_total} WHERE word = '%s'", $word));
      if (!$exists) {
        db_query("INSERT INTO {search_total} (word, count) VALUES ('%s', %d)", $word, $total);
      }
Dries's avatar
Dries committed
201 202 203 204 205 206 207 208
    }
  }
  // Find words that were deleted from search_index, but are still in
  // search_total. We use a LEFT JOIN between the two tables and keep only the
  // rows which fail to join.
  $result = db_query("SELECT t.word AS realword, i.word FROM {search_total} t LEFT JOIN {search_index} i ON t.word = i.word WHERE i.word IS NULL");
  while ($word = db_fetch_object($result)) {
    db_query("DELETE FROM {search_total} WHERE word = '%s'", $word->realword);
Kjartan's avatar
Kjartan committed
209 210 211 212
  }
}

/**
213
 * Splits a string into component words according to indexing rules.
Kjartan's avatar
Kjartan committed
214
 */
215 216 217
function search_keywords_split($text) {
  static $last = null;
  static $lastsplit = null;
Kjartan's avatar
Kjartan committed
218

219 220 221
  if ($last == $text) {
    return $lastsplit;
  }
Kjartan's avatar
Kjartan committed
222

223 224
  // Decode entities to UTF-8
  $text = decode_entities($text);
225

226 227
  // Call an external processor for word handling.
  search_preprocess($text);
Kjartan's avatar
Kjartan committed
228

229 230 231 232 233 234 235
  // To improve searching for numerical data such as dates, IP addresses
  // or version numbers, we consider a group of numerical characters
  // separated only by punctuation characters to be one piece.
  // This also means that searching for e.g. '20/03/1984' also returns
  // results with '20-03-1984' in them.
  // Readable regexp: ([number]+)[punctuation]+(?=[number])
  $text = preg_replace('/(['. PREG_CLASS_NUMBERS .']+)['. PREG_CLASS_PUNCTUATION .']+(?=['. PREG_CLASS_NUMBERS .'])/u', '\1', $text);
Kjartan's avatar
Kjartan committed
236

237 238 239
  // The dot, underscore and dash are simply removed. This allows meaningful
  // search behaviour with acronyms and URLs.
  $text = preg_replace('/[._-]+/', '', $text);
Kjartan's avatar
Kjartan committed
240

241 242 243
  // With the exception of the rules above, we consider all punctuation,
  // marks, spacers, etc, to be a word boundary.
  $text = preg_replace('/['. PREG_CLASS_SEARCH_EXCLUDE . ']+/u', ' ', $text);
Kjartan's avatar
Kjartan committed
244

245 246
  // Process words
  $words = explode(' ', $text);
247
  array_walk($words, '_search_keywords_truncate');
Kjartan's avatar
Kjartan committed
248

249 250 251 252 253 254 255
  // Save last keyword result
  $last = $text;
  $lastsplit = $words;

  return $words;
}

256 257 258 259
/**
 * Helper function for array_walk in search_keywords_split.
 */
function _search_keywords_truncate(&$text) {
Steven Wittens's avatar
Steven Wittens committed
260
  $text = truncate_utf8($text, 50);
261 262
}

263 264 265 266 267 268 269 270 271 272 273 274
/**
 * Invokes hook_search_preprocess() in modules.
 */
function search_preprocess(&$text) {
  static $modules = null;
  // Cache list of modules which implement this hook. This function gets called
  // a lot during reindexing.
  if (!is_array($modules)) {
    $modules = array();
    foreach (module_list() as $module) {
      if (module_hook($module, 'search_preprocess')) {
        $modules[] = $module;
Dries's avatar
 
Dries committed
275 276 277
      }
    }
  }
278 279 280 281
  // Process $text
  if (count($modules) > 0) {
    foreach ($modules as $module) {
      $text = module_invoke($module, 'search_preprocess', $text);
Kjartan's avatar
Kjartan committed
282 283 284 285
    }
  }
}

286

Kjartan's avatar
Kjartan committed
287
/**
Steven Wittens's avatar
Steven Wittens committed
288
 * Update the full-text search index for a particular item.
289 290 291
 *
 * @param $sid
 *   A number identifying this particular item (e.g. node id).
Kjartan's avatar
Kjartan committed
292
 *
293 294 295 296 297
 * @param $type
 *   A string defining this type of item (e.g. 'node')
 *
 * @param $text
 *   The content of this item. Must be a piece of HTML text.
298 299
 *
 * @ingroup search
Kjartan's avatar
Kjartan committed
300
 */
301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349
function search_index($sid, $type, $text) {
  $minimum_word_size = variable_get('minimum_word_size', 3);

  global $base_url;
  $node_regexp = '!href=[\'"]?(?:'. preg_quote($base_url) .'/)?(?:\?q=)?([^\'">]+)[\'">]!i';

  // Multipliers for scores of words inside certain HTML tags.
  // Note: 'a' must be included for link ranking to work.
  $tags = array('h1' => 21,
                'h2' => 18,
                'h3' => 15,
                'h4' => 12,
                'h5' => 9,
                'h6' => 6,
                'u' => 5,
                'b' => 5,
                'strong' => 5,
                'em' => 5,
                'a' => 10);

  // Strip off all ignored tags to speed up processing, but insert space before/after
  // them to keep word boundaries.
  $text = str_replace(array('<', '>'), array(' <', '> '), $text);
  $text = strip_tags($text, '<'. implode('><', array_keys($tags)) .'>');

  // Split HTML tags from plain text.
  $split = preg_split('/\s*<([^>]+?)>\s*/', $text, -1, PREG_SPLIT_DELIM_CAPTURE);
  // Note: PHP ensures the array consists of alternating delimiters and literals
  // and begins and ends with a literal (inserting $null as required).

  $tag = false; // Odd/even counter. Tag or no tag.
  $link = false; // State variable for link analyser
  $score = 1; // Starting score per word

  $results = array(0 => array());

  foreach ($split as $value) {
    if ($tag) {
      // Increase or decrease score per word based on tag
      list($tagname) = explode(' ', $value, 2);
      $tagname = strtolower($tagname);
      if ($tagname{0} == '/') {
        $score -= $tags[substr($tagname, 1)];
        if ($score < 1) { // possible due to bad HTML
          $score = 1;
        }
        if ($tagname == '/a') {
          $link = false;
        }
Kjartan's avatar
Kjartan committed
350
      }
351 352 353 354 355
      else {
        if ($tagname == 'a') {
          // Check if link points to a node on this site
          if (preg_match($node_regexp, $value, $match)) {
            $path = drupal_get_normal_path($match[1]);
356
            if (preg_match('!(?:node|book)/(?:view/)?([0-9]+)!i', $path, $match)) {
357 358 359 360 361
              $linknid = $match[1];
              if ($linknid > 0) {
                $link = true;
              }
            }
Kjartan's avatar
Kjartan committed
362 363
          }
        }
364
        $score += $tags[$tagname];
Kjartan's avatar
Kjartan committed
365
      }
366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384
    }
    else {
      // Note: use of PREG_SPLIT_DELIM_CAPTURE above will introduce empty values
      if ($value != '') {
        $words = search_keywords_split($value);
        foreach ($words as $word) {
          // Check wordlength
          if (string_length($word) >= $minimum_word_size) {
            $word = strtolower($word);
            if ($link) {
              if (!isset($results[$linknid])) {
                $results[$linknid] = array();
              }
              $results[$linknid][$word] += $score;
            }
            else {
              $results[0][$word] += $score;
            }
          }
Dries's avatar
 
Dries committed
385
        }
Kjartan's avatar
Kjartan committed
386 387
      }
    }
388
    $tag = !$tag;
Kjartan's avatar
Kjartan committed
389 390
  }

391
  search_wipe($sid, $type);
Kjartan's avatar
Kjartan committed
392

393 394 395 396 397 398
  // Insert results into search index
  foreach ($results[0] as $word => $score) {
    db_query("INSERT INTO {search_index} (word, sid, type, score) VALUES ('%s', %d, '%s', %d)", $word, $sid, $type, $score);
    search_dirty($word);
  }
  unset($results[0]);
Dries's avatar
 
Dries committed
399

400 401 402 403 404
  // Now insert links to nodes
  foreach ($results as $nid => $words) {
    foreach ($words as $word => $score) {
      db_query("INSERT INTO {search_index} (word, sid, type, fromsid, fromtype, score) VALUES ('%s', %d, '%s', %d, '%s', %d)", $word, $nid, 'node', $sid, $type, $score);
      search_dirty($word);
Kjartan's avatar
Kjartan committed
405 406 407 408 409
    }
  }
}

/**
Steven Wittens's avatar
Steven Wittens committed
410
 * Do a query on the full-text search index for a word or words.
411
 *
Steven Wittens's avatar
Steven Wittens committed
412 413
 * This function is normally only called by each module that support the
 * indexed search (and thus, implements hook_update_index()).
414
 *
415
 * The final query is an SQL select on the search_index table. As a guide for
416 417 418 419 420 421 422 423 424 425 426 427 428 429
 * writing the optional extra SQL fragments (see below), use this query:
 *
 * SELECT i.type, i.sid, i.word, SUM(i.score/t.count) AS score
 * FROM {search_index} i
 * $join INNER JOIN {search_total} t ON i.word = t.word
 * WHERE $where AND (i.word = '...' OR ...)
 * GROUP BY i.type, i.sid
 * ORDER BY score DESC";
 *
 * @param $keys
 *   A search string as entered by the user.
 *
 * @param $type
 *   A string identifying the calling module.
Kjartan's avatar
Kjartan committed
430
 *
431 432 433 434 435 436 437 438 439 440
 * @param $join
 *   (optional) A string to be inserted into the JOIN part of the SQL query.
 *   For example "INNER JOIN {node} n ON n.nid = i.sid".
 *
 * @param $where
 *   (optional) A string to be inserted into the WHERE part of the SQL query.
 *   For example "(n.status > 0)".
 *
 * @return
 *   An array of SIDs for the search results.
441 442
 *
 * @ingroup search
Kjartan's avatar
Kjartan committed
443
 */
444 445 446
function do_search($keys, $type, $join = '', $where = '1') {
  // Note, we replace the wildcards with U+FFFD (Replacement character) to pass
  // through the keyword extractor.
Steven Wittens's avatar
Steven Wittens committed
447
  $keys = str_replace('*', '�', $keys);
448 449 450 451 452 453 454 455 456 457 458 459 460 461 462

  // Split into words
  $keys = search_keywords_split($keys);
  // Lowercase
  foreach ($keys as $k => $v) {
    $keys[$k] = strtolower($v);
  }

  $words = array();
  $arguments = array();
  // Build WHERE clause
  foreach ($keys as $word) {
    if (string_length($word) < variable_get('remove_short', 3)) {
      continue;
    }
Steven Wittens's avatar
Steven Wittens committed
463
    if (strpos($word, '�') !== false) {
464
      $words[] = "i.word LIKE '%s'";
Steven Wittens's avatar
Steven Wittens committed
465
      $arguments[] = str_replace('�', '%', $word);
466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485
    }
    else {
      $words[] = "i.word = '%s'";
      $arguments[] = $word;
    }
  }
  if (count($words) == 0) {
    return array();
  }
  $where .= ' AND ('. implode(' OR ', $words) .')';

  // Get result count (for pager)
  $count = db_result(db_query("SELECT COUNT(DISTINCT i.sid, i.type) FROM {search_index} i $join WHERE $where", $arguments));
  if ($count == 0) {
    return array();
  }
  $count_query = "SELECT $count";

  // Do pager query
  $query = "SELECT i.type, i.sid, i.word, SUM(i.score/t.count) AS score FROM {search_index} i $join INNER JOIN {search_total} t ON i.word = t.word WHERE $where GROUP BY i.type, i.sid ORDER BY score DESC";
486
  $result = pager_query($query, 15, 0, $count_query, $arguments);
487 488 489 490 491 492 493

  $results = array();
  while ($item = db_fetch_object($result)) {
    $results[] = $item->sid;
  }

  return $results;
Kjartan's avatar
Kjartan committed
494 495
}

Dries's avatar
 
Dries committed
496 497 498 499
/**
 * Menu callback; presents the search form and/or search results.
 */
function search_view() {
500
  $keys = isset($_GET['keys']) ? $_GET['keys'] : $_POST['edit']['keys'];
Dries's avatar
Dries committed
501
  $type = arg(1) ? arg(1) : (isset($_GET['type']) ? $_GET['type'] : ($_POST['edit']['type'] ? $_POST['edit']['type'] : 'node'));
Dries's avatar
 
Dries committed
502

Dries's avatar
 
Dries committed
503
  if (user_access('search content')) {
504 505 506
    // Only perform search if there is non-whitespace search term:
    if (trim($keys)) {
      // Log the search keys:
Dries's avatar
Dries committed
507 508
      watchdog('search',
        t('Search: %keys (%type).', array('%keys' => "<em>$keys</em>", '%type' => module_invoke($type, 'search', 'name'))),
Dries's avatar
Dries committed
509
        WATCHDOG_NOTICE,
Dries's avatar
Dries committed
510 511
        l(t('results'), 'search', NULL, 'keys='. urlencode($keys) . '&type='. urlencode($type))
        );
Dries's avatar
 
Dries committed
512

513
      // Collect the search results:
514
      $results = search_data($keys, $type);
Dries's avatar
 
Dries committed
515

Dries's avatar
 
Dries committed
516
      if ($results) {
517
        $results = theme('box', t('Search results'), $results);
Dries's avatar
 
Dries committed
518 519
      }
      else {
520
        $results = theme('box', t('Your search yielded no results'), search_help('search#noresults'));
Dries's avatar
 
Dries committed
521
      }
Dries's avatar
 
Dries committed
522
    }
523 524 525 526 527 528 529 530 531
    else if (isset($_POST['edit'])) {
      form_set_error('keys', t('Please enter some keywords.'));
    }

    // Construct the search form.
    // Note, we do this last because of the form_set_error() above.
    $output = search_form(NULL, $keys, $type, TRUE);

    $output .= $results;
Dries's avatar
 
Dries committed
532

533
    print theme('page', $output);
534
  }
Dries's avatar
 
Dries committed
535
  else {
Dries's avatar
 
Dries committed
536
    drupal_access_denied();
Dries's avatar
 
Dries committed
537
  }
Kjartan's avatar
Kjartan committed
538 539 540

}

541 542 543 544 545 546 547 548
/**
 * @defgroup search Search interface
 * @{
 * The Drupal search interface manages a global search mechanism.
 *
 * Modules may plug into this system to provide searches of different types of
 * data. Most of the system is handled by search.module, so this must be enabled
 * for all of the search features to work.
549 550 551 552 553 554 555 556 557 558 559 560 561 562 563
 *
 * There are three ways to interact with the search system:
 * - Specifically for searching nodes, you can implement nodeapi('update index')
 *   and nodeapi('search result'). However, note that the search system already
 *   indexes all visible output of a node, i.e. everything displayed normally
 *   by hook_view() and hook_nodeapi('view'). This is usually sufficient.
 *   You should only use this mechanism if you want additional, non-visible data
 *   to be indexed.
 * - Implement hook_search(). This will create a search tab for your module on
 *   the /search page with a simple keyword search form. You may optionally
 *   implement hook_search_item() to customize the display of your results.
 * - Implement hook_update_index(). This allows your module to use Drupal's
 *   HTML indexing mechanism for searching full text efficiently.
 *
 * If your module needs to provide a more complicated search form, then you need
Dries's avatar
Dries committed
564
 * to implement it yourself without hook_search(). In that case, you should
565 566
 * define it as a local task (tab) under the /search page (e.g. /search/mymodule)
 * so that users can easily find it.
567 568 569 570 571 572 573 574 575
 */

/**
 * Render a search form.
 *
 * @param $action
 *   Form action. Defaults to "search".
 * @param $keys
 *   The search string entered by the user, containing keywords for the search.
576 577 578
 * @param $type
 *   The type of search to render the node for. Must be the name of module
 *   which implements hook_search(). Defaults to 'node'.
579 580 581
 * @return
 *   An HTML string containing the search form.
 */
582
function search_form($action = '', $keys = '', $type = null) {
583 584 585
  $edit = $_POST['edit'];

  if (!$action) {
586
    $action = url('search/'. $type);
587
  }
Dries's avatar
Dries committed
588 589 590
  if (!$type) {
    $type = 'node';
  }
591 592 593 594 595 596 597

  $output = ' <div class="search-form">';
  $box = '<div class="container-inline">';
  $box .= form_textfield('', 'keys', $keys, 40, 255);
  $box .= form_submit(t('Search'));;
  $box .= '</div>';
  $output .= form_item(t('Enter your keywords'), $box);
Dries's avatar
Dries committed
598
  $output .= form_hidden('type', $type);
599 600 601 602 603 604
  $output .= '</div>';

  return form($output, 'post', $action);
}

/**
Steven Wittens's avatar
Steven Wittens committed
605
 * Perform a standard search on the given keys, and return the formatted results.
606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643
 */
function search_data($keys = NULL, $type = 'node') {
  $output = '';

  if (isset($keys)) {
    if (module_hook($type, 'search')) {
      $results = module_invoke($type, 'search', 'search', $keys);
      if (is_array($results) && count($results)) {
        $output .= '<dl class="search-results">';
        foreach ($results as $entry) {
          $output .= theme('search_item', $entry, $type);
        }
        $output .= '</dl>';
        $output .= theme('pager', NULL, 15, 0, array('keys' => $keys, 'type' => $type));
      }
    }
  }

  return $output;
}

/**
 * Returns snippets from a piece of text, with certain keywords highlighted.
 * Used for formatting search results.
 *
 * @param $keys
 *   A string containing keywords. They are split into words using the same
 *   rules as search indexing.
 *
 * @param $text
 *   The text to extract fragments from.
 *
 * @return
 *   A string containing HTML for the excerpt.
 */
function search_excerpt($keys, $text) {
  $keys = search_keywords_split($keys);
  $text = strip_tags(str_replace(array('<', '>'), array(' <', '> '), $text));
644 645
  array_walk($keys, '_search_excerpt_replace');
  $workkeys = $keys;
646 647 648 649

  // Extract a fragment per keyword for at most 4 keywords.
  // First we collect ranges of text around each keyword, starting/ending
  // at spaces.
650
  // If the sum of all fragments is too short, we look for second occurences.
651 652 653
  $ranges = array();
  $included = array();
  $length = 0;
654 655
  while ($length < 256 && count($workkeys)) {
    foreach ($workkeys as $k => $key) {
656
      if (strlen($key) == 0) {
657
        unset($workkeys[$k]);
658 659 660 661 662 663 664 665 666 667
        continue;
      }
      if ($length >= 256) {
        break;
      }
      // Remember occurence of key so we can skip over it if more occurences
      // are desired.
      if (!isset($included[$key])) {
        $included[$key] = 0;
      }
668 669 670 671
      // Locate a keyword (position $p), then locate a space in front (position
      // $q) and behind it (position $s)
      if (preg_match('/\b'. $key .'\b/iu', $text, $match, PREG_OFFSET_CAPTURE, $included[$key])) {
        $p = $match[0][1];
672 673 674 675 676 677 678 679
        if (($q = strpos($text, ' ', max(0, $p - 60))) !== false) {
          $end = substr($text, $p, 80);
          if (($s = strrpos($end, ' ')) !== false) {
            $ranges[$q] = $p + $s;
            $length += $p + $s - $q;
            $included[$key] = $p + 1;
          }
          else {
680
            unset($workkeys[$k]);
681 682 683
          }
        }
        else {
684
          unset($workkeys[$k]);
685 686 687
        }
      }
      else {
688
        unset($workkeys[$k]);
689 690
      }
    }
691
  }
692

693 694 695
  // If we didn't find anything, return the beginning.
  if (count($ranges) == 0) {
    return truncate_utf8($text, 256) . ' ...';
696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724
  }

  // Sort the text ranges by starting position.
  ksort($ranges);

  // Now we collapse overlapping text ranges into one. The sorting makes it O(n).
  $newranges = array();
  foreach ($ranges as $from2 => $to2) {
    if (!isset($from1)) {
      $from1 = $from2;
      $to1 = $to2;
      continue;
    }
    if ($from2 <= $to1) {
      $to1 = max($to1, $to2);
    }
    else {
      $newranges[$from1] = $to1;
      $from1 = $from2;
      $to1 = $to2;
    }
  }
  $newranges[$from1] = $to1;

  // Fetch text
  $out = array();
  foreach ($newranges as $from => $to) {
    $out[] = substr($text, $from, $to - $from);
  }
725
  $text = (isset($newranges[0]) ? '' : '... '). implode(' ... ', $out) .' ...';
726 727

  // Highlight keywords. Must be done at once to prevent conflicts ('strong' and '<strong>').
728
  $text = preg_replace('/\b('. implode('|', $keys) .')\b/iu', '<strong>\0</strong>', $text);
729 730 731
  return $text;
}

732 733 734 735
/**
 * @} End of "defgroup search".
 */

736 737 738
/**
 * Helper function for array_walk in search_except.
 */
739 740
function _search_excerpt_replace(&$text) {
  $text = preg_quote($text, '/');
741 742 743 744 745 746 747 748 749 750
}

/**
 * Format a single result entry of a search query.
 *
 * Modules may implement hook_search_item() in order to override this default
 * function to display search results.
 *
 * @param $item
 *   A single search result as returned by hook_search(). The result should be
Dries's avatar
Dries committed
751 752 753
 *   an array with keys "link", "title", "type", "user", "date", and "snippet".
 *   Optionally, "extra" can be an array of extra info to show along with the
 *   result.
754
 * @param $type
755 756 757
 *   The type of item found, such as "user" or "node".
 *
 * @ingroup themeable
758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774
 */
function theme_search_item($item, $type) {
  if (module_hook($type, 'search_item')) {
    $output = module_invoke($type, 'search_item', $item);
  }
  else {
    $output = ' <dt class="title"><a href="'. $item['link'] .'">'. $item['title'] .'</a></dt>';
    $info = array();
    if ($item['type']) {
      $info[] = $item['type'];
    }
    if ($item['user']) {
      $info[] = $item['user'];
    }
    if ($item['date']) {
      $info[] = format_date($item['date'], 'small');
    }
Dries's avatar
Dries committed
775 776
    if (is_array($item['extra'])) {
      $info = array_merge($info, $item['extra']);
777 778 779 780 781 782 783 784
    }
    $output .= ' <dd>'. ($item['snippet'] ? '<p>'. $item['snippet'] . '</p>' : '') . '<p class="search-info">' . implode(' - ', $info) .'</p></dd>';
  }

  return $output;
}


Dries's avatar
 
Dries committed
785
?>