NodeGrantDatabaseStorage::alterQuery

public NodeGrantDatabaseStorage::alterQuery($query, array $tables, $op, AccountInterface $account, $base_table)

public function alterQuery($query, array $tables, $op, AccountInterface $account, $base_table) {
  if (!$langcode = $query->getMetaData('langcode')) {
    $langcode = FALSE;
  }

  // Find all instances of the base table being joined -- could appear
  // more than once in the query, and could be aliased. Join each one to
  // the node_access table.
  $grants = node_access_grants($op, $account);
  foreach ($tables as $nalias => $tableinfo) {
    $table = $tableinfo['table'];
    if (!($table instanceof SelectInterface) && $table == $base_table) {
      // Set the subquery.
      $subquery = $this->database->select('node_access', 'na')
        ->fields('na', array('nid'));

      // If any grant exists for the specified user, then user has access to the
      // node for the specified operation.
      $grant_conditions = static::buildGrantsQueryCondition($grants);

      // Attach conditions to the subquery for nodes.
      if (count($grant_conditions->conditions())) {
        $subquery->condition($grant_conditions);
      }
      $subquery->condition('na.grant_' . $op, 1, '>=');

      // Add langcode-based filtering if this is a multilingual site.
      if (\Drupal::languageManager()->isMultilingual()) {
        // If no specific langcode to check for is given, use the grant entry
        // which is set as a fallback.
        // If a specific langcode is given, use the grant entry for it.
        if ($langcode === FALSE) {
          $subquery->condition('na.fallback', 1, '=');
        }
        else {
          $subquery->condition('na.langcode', $langcode, '=');
        }
      }

      $field = 'nid';
      // Now handle entities.
      $subquery->where("$nalias.$field = na.nid");

      $query->exists($subquery);
    }
  }
}