search_index

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Definition

search_index($sid, $type, $text)
modules/search.module, line 323

Description

Update the full-text search index for a particular item.

Parameters

$sid A number identifying this particular item (e.g. node id).

$type A string defining this type of item (e.g. 'node')

$text The content of this item. Must be a piece of HTML text.

Related topics

Name	Description
Search interface	The Drupal search interface manages a global search mechanism.

Code

<?php
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') {
          $link = false;
        }
      }
      else {
        if ($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]);
            if (preg_match('!(?:node|book)/(?:view/)?([0-9]+)!i', $path, $match)) {
              $linknid = $match[1];
              if ($linknid > 0) {
                $link = true;
              }
            }
          }
        }
        $score += $tags[$tagname];
      }
    }
    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) {
            // Note: strtolower can be used because the value is only used internally.
            $word = strtolower($word);
            if ($link) {
              if (!isset($results[$linknid])) {
                $results[$linknid] = array();
              }
              $results[$linknid][$word] += $score;
            }
            else {
              $results[0][$word] += $score;
            }
          }
        }
      }
    }
    $tag = !$tag;
  }

  search_wipe($sid, $type);

  // 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]);

  // 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);
    }
  }
}
?>