facetapi_luceneapi.adapter.inc in Facet API 6

Classes used by the Facet API module.

File

contrib/facetapi_luceneapi/facetapi_luceneapi.adapter.inc

<?php

/**
 * @file
 * Classes used by the Facet API module.
 */

/**
 * Facet API adapter for Search Lucene API modules.
 */
class FacetapiLuceneapiAdapter extends FacetapiAdapter {

  /**
   * Returns a boolean flagging whether $this->_searcher executed a search.
   */
  public function searchExecuted() {
    return luceneapi_search_executed() == $this->_searcher;
  }

  /**
   * The default method used to retrieve facet data.
   */
  public function fetchTerm(array $facet) {
    $facet_items = array();
    $sql = "\n      SELECT term\n      FROM {" . $this
      ->getSearcher() . "_termfreqs}\n      WHERE field = '%s'\n    ";

    // Gets the cached term frequencies.
    if ($result = db_query($sql, array(
      $facet['field'],
    ))) {
      while ($record = db_fetch_object($result)) {
        $term = new Zend_Search_Lucene_Index_Term($record->term, $facet['field']);
        if ($count = facetapi_luceneapi_terms_count($this->_index, $this->_docs, array(
          $term,
        ))) {
          $facet_items[$record->term] = array(
            'count' => $count,
          );
        }
      }
    }
    return $facet_items;
  }

  /**
   * Fetches data from facets that filter results by date ranges.
   */
  public function fetchDate(array $facet) {
    $sql = "\n      SELECT MIN(term) as minimum, MAX(term) as maximum\n      FROM {" . $this
      ->getSearcher() . "_termfreqs}\n      WHERE field = '%s'\n    ";

    // Calculates the minimum and maximum values.
    $range = array();
    if ($result = db_query($sql, array(
      $facet['field'],
    ))) {
      if ($record = db_fetch_object($result)) {
        $range = array(
          $record->minimum,
          $record->maximum,
        );
      }
    }

    // Gets all values in the resultset.
    $raw_values = array();
    foreach (facetapi_luceneapi_range_matches_get($this->_index, $range[0], $range[1], TRUE, array(
      $facet['field'],
    )) as $key => $term) {
      if ($count = facetapi_luceneapi_terms_count($this->_index, $this->_docs, array(
        $term,
      ))) {
        $raw_values[$term->text] = $count;
      }
    }

    // Sorts by timestamp if there are values, otherwise return an empty array.
    if (!empty($raw_values)) {
      $facet_items = array();
      ksort($raw_values);
    }
    else {
      return array();
    }

    // Gets the active date facets, starts to builds the "parent - child"
    // relationships.
    $parent = NULL;
    $gap = NULL;
    foreach ($this
      ->getActiveFacets($facet['field alias']) as $value => $active_facet) {

      // Strips field from value, adds to $facet_items array.
      $facet_items[$value] = array(
        'count' => count($this->_docs),
      );

      // Gets next "gap" increment, mintue being the lowest be can go.
      $gap = facetapi_next_date_gap_get(facetapi_date_gap_get($active_facet['start'], $active_facet['end']), FACETAPI_DATE_MINUTE);

      // If there is a previous item, there is a parent, uses a reference so the
      // arrays are populated when they are updated.
      if (NULL !== $parent) {
        $facet_items[$parent]['children'][$value] =& $facet_items[$value];
        $facet_items[$value]['parents'][$parent] = $parent;
      }

      // Stores the last value iterated over.
      $parent = $value;
    }

    // Mind the gap! Calculates gap from min and max timestamps.
    $timestamps = array_keys($raw_values);
    if (NULL === $parent) {
      if (count($raw_values) > 1) {
        $gap = facetapi_timestamp_gap_get(min($timestamps), max($timestamps));
      }
      else {
        $gap = FACETAPI_DATE_HOUR;
      }
    }

    // Converts all timestamps to dates in ISO 8601 format.
    $dates = array_combine($timestamps, $timestamps);
    array_walk($dates, 'facetapi_luceneapi_timestamp_convert', $gap);

    // Treat each date as the range start and next data as the range end.
    $range_end = array();
    $previous = NULL;
    foreach (array_unique($dates) as $date) {
      if (NULL !== $previous) {
        $range_end[$previous] = facetapi_next_date_increment_get($previous, $gap);
      }
      $previous = $date;
    }
    $range_end[$previous] = facetapi_next_date_increment_get($previous, $gap);

    // Groups dates by the range they belong to, builds the $facet_items array
    // with the facet counts and formatted range values.
    foreach ($raw_values as $value => $count) {
      $new_value = '[' . $dates[$value] . ' TO ' . $range_end[$dates[$value]] . ']';
      if (!isset($facet_items[$new_value])) {
        $facet_items[$new_value] = array(
          'count' => $count,
        );
      }
      else {
        $facet_items[$new_value]['count'] += $count;
      }

      // Adds parent information if not already set.
      if (NULL !== $parent && !isset($facet_items[$new_value]['parents'])) {
        $facet_items[$parent]['children'][$new_value] =& $facet_items[$new_value];
        $facet_items[$new_value]['parents'][$parent] = $parent;
      }
    }

    // Returns the dates.
    return $facet_items;
  }

  /**
   * Overrides the fetch() function, prepopulates the termFreqs cache by calling
   * the facetapi_luceneapi_termfreqs_get() function.
   */
  public function fetch(array $facet) {
    $term = new Zend_Search_Lucene_Index_Term(NULL, $facet['field']);
    facetapi_luceneapi_termfreqs_get($this
      ->getSearcher(), $term);
    return parent::fetch($facet);
  }

  /**
   * Returns a normalized array with facet counts included.
   */
  public function getFacetData(array $facet) {

    // Opens the index, returns an empty index in it cannot be opened.
    if (!($this->_index = luceneapi_index_open($this
      ->getSearcher(), $errstr))) {
      luceneapi_throw_error($errstr);
      return array();
    }

    // Ugly. We have to re-build the query.
    // @todo Add an API function similar to apachesolr_current_query().
    // Gets query container, appends user query and facet queries.
    if (!($query = luceneapi_query_get('boolean'))) {
      throw new LuceneAPI_Exception(t('Error instantiating boolean query.'));
    }

    // Parses user query if a string was passed.
    $user_query = luceneapi_query_parse(search_get_keys(), $this
      ->getSearcher(), 'keys');
    if (!$user_query || form_get_errors()) {
      return array();
    }

    // Adds user query to query container, allows modules to alter the query.
    luceneapi_subquery_add($query, $user_query, 'required', TRUE);
    module_invoke_all('luceneapi_query_alter', $query, $this
      ->getSearcher(), $this
      ->getType());

    // Gets documents matched in the query.
    $this->_docs = facetapi_luceneapi_match_query($this->_index, $query);
    return parent::getFacetData($realm_name, $facets);
  }

  /**
   * Returns the search keys.
   */
  public function getSearchKeys() {
    if (NULL === $this->_keys) {
      return search_get_keys();
    }
    return $this->_keys;
  }

}

Classes

Name	Description
FacetapiLuceneapiAdapter	Facet API adapter for Search Lucene API modules.