function node_search

Implementation of hook_search().

File

modules/node/node.module, line 1158

The core that allows content to be submitted to the site. Modules and scripts may programmatically submit nodes using the usual form API pattern.

Code

function node_search($op = 'search', $keys = NULL) {
  switch ($op) {
    case 'name':
      return t('Content');
    case 'reset':
      db_query("UPDATE {search_dataset} SET reindex = %d WHERE type = 'node'", time());
      return;
    case 'status':
      $total = db_result(db_query('SELECT COUNT(*) FROM {node} WHERE status = 1'));
      $remaining = db_result(db_query("SELECT COUNT(*) FROM {node} n LEFT JOIN {search_dataset} d ON d.type = 'node' AND d.sid = n.nid WHERE n.status = 1 AND (d.sid IS NULL OR d.reindex <> 0)"));
      return array(
        'remaining' => $remaining,
        'total' => $total,
      );
    case 'admin':
      $form = array();

      // Output form for defining rank factor weights.
      $form['content_ranking'] = array(
        '#type' => 'fieldset',
        '#title' => t('Content ranking'),
      );
      $form['content_ranking']['#theme'] = 'node_search_admin';
      $form['content_ranking']['info'] = array(
        '#value' => '<em>' . t('The following numbers control which properties the content search should favor when ordering the results. Higher numbers mean more influence, zero means the property is ignored. Changing these numbers does not require the search index to be rebuilt. Changes take effect immediately.') . '</em>',
      );
      $ranking = array(
        'node_rank_relevance' => t('Keyword relevance'),
        'node_rank_recent' => t('Recently posted'),
      );
      if (module_exists('comment')) {
        $ranking['node_rank_comments'] = t('Number of comments');
      }
      if (module_exists('statistics') && variable_get('statistics_count_content_views', 0)) {
        $ranking['node_rank_views'] = t('Number of views');
      }

      // Note: reversed to reflect that higher number = higher ranking.
      $options = drupal_map_assoc(range(0, 10));
      foreach ($ranking as $var => $title) {
        $form['content_ranking']['factors'][$var] = array(
          '#title' => $title,
          '#type' => 'select',
          '#options' => $options,
          '#default_value' => variable_get($var, 5),
        );
      }
      return $form;
    case 'search':

      // Build matching conditions
      list($join1, $where1) = _db_rewrite_sql();
      $arguments1 = array();
      $conditions1 = 'n.status = 1';
      if ($type = search_query_extract($keys, 'type')) {
        $types = array();
        foreach (explode(',', $type) as $t) {
          $types[] = "n.type = '%s'";
          $arguments1[] = $t;
        }
        $conditions1 .= ' AND (' . implode(' OR ', $types) . ')';
        $keys = search_query_insert($keys, 'type');
      }
      if ($category = search_query_extract($keys, 'category')) {
        $categories = array();
        foreach (explode(',', $category) as $c) {
          $categories[] = "tn.tid = %d";
          $arguments1[] = $c;
        }
        $conditions1 .= ' AND (' . implode(' OR ', $categories) . ')';
        $join1 .= ' INNER JOIN {term_node} tn ON n.vid = tn.vid';
        $keys = search_query_insert($keys, 'category');
      }

      // Build ranking expression (we try to map each parameter to a
      // uniform distribution in the range 0..1).
      $ranking = array();
      $arguments2 = array();
      $join2 = '';

      // Used to avoid joining on node_comment_statistics twice
      $stats_join = FALSE;
      $total = 0;
      if ($weight = (int) variable_get('node_rank_relevance', 5)) {

        // Average relevance values hover around 0.15
        $ranking[] = '%d * i.relevance';
        $arguments2[] = $weight;
        $total += $weight;
      }
      if ($weight = (int) variable_get('node_rank_recent', 5)) {

        // Exponential decay with half-life of 6 months, starting at last indexed node
        // c.last_comment_timestamp may be NULL. Since both MAX(anynumber, NULL) and
        // GREATEST(anynumber, NULL) return NULL, we use COALESCE(MAX(c.last_comment_timestamp), 0)
        // to prevent it from being NULL.
        $ranking[] = '%d * POW(2, (GREATEST(MAX(n.created), MAX(n.changed), COALESCE(MAX(c.last_comment_timestamp), 0)) - %d) * 6.43e-8)';
        $arguments2[] = $weight;
        $arguments2[] = (int) variable_get('node_cron_last', 0);
        $join2 .= ' LEFT JOIN {node_comment_statistics} c ON c.nid = i.sid';
        $stats_join = TRUE;
        $total += $weight;
      }
      if (module_exists('comment') && ($weight = (int) variable_get('node_rank_comments', 5))) {

        // Inverse law that maps the highest reply count on the site to 1 and 0 to 0.
        $scale = variable_get('node_cron_comments_scale', 0.0);
        $ranking[] = '%d * (2.0 - 2.0 / (1.0 + MAX(c.comment_count) * %f))';
        $arguments2[] = $weight;
        $arguments2[] = $scale;
        if (!$stats_join) {
          $join2 .= ' LEFT JOIN {node_comment_statistics} c ON c.nid = i.sid';
        }
        $total += $weight;
      }
      if (module_exists('statistics') && variable_get('statistics_count_content_views', 0) && ($weight = (int) variable_get('node_rank_views', 5))) {

        // Inverse law that maps the highest view count on the site to 1 and 0 to 0.
        $scale = variable_get('node_cron_views_scale', 0.0);
        $ranking[] = '%d * (2.0 - 2.0 / (1.0 + MAX(nc.totalcount) * %f))';
        $arguments2[] = $weight;
        $arguments2[] = $scale;
        $join2 .= ' LEFT JOIN {node_counter} nc ON nc.nid = i.sid';
        $total += $weight;
      }

      // When all search factors are disabled (ie they have a weight of zero),
      // the default score is based only on keyword relevance and there is no need to
      // adjust the score of each item.
      if ($total == 0) {
        $select2 = 'i.relevance AS score';
        $total = 1;
      }
      else {
        $select2 = implode(' + ', $ranking) . ' AS score';
      }

      // Do search.
      $find = do_search($keys, 'node', 'INNER JOIN {node} n ON n.nid = i.sid ' . $join1, $conditions1 . (empty($where1) ? '' : ' AND ' . $where1), $arguments1, $select2, $join2, $arguments2);

      // Load results.
      $results = array();
      foreach ($find as $item) {

        // Build the node body.
        $node = node_load($item->sid);
        $node->build_mode = NODE_BUILD_SEARCH_RESULT;
        $node = node_build_content($node, FALSE, FALSE);
        $node->body = drupal_render($node->content);

        // Fetch comments for snippet.
        if (module_exists('comment')) {
          $node->body .= comment_nodeapi($node, 'update index');
        }

        // Fetch terms for snippet.
        if (module_exists('taxonomy')) {
          $node->body .= taxonomy_nodeapi($node, 'update index');
        }
        $extra = node_invoke_nodeapi($node, 'search result');
        $results[] = array(
          'link' => url('node/' . $item->sid, array(
            'absolute' => TRUE,
          )),
          'type' => check_plain(node_get_types('name', $node)),
          'title' => $node->title,
          'user' => theme('username', $node),
          'date' => $node->changed,
          'node' => $node,
          'extra' => $extra,
          'score' => $item->score / $total,
          'snippet' => search_excerpt($keys, $node->body),
        );
      }
      return $results;
  }
}