abstract class FacetapiUrlProcessor in Facet API 7.2

Abstract class extended by url processor plugins.

Url processor plugins provide a pluggable method of retrieving facet data. Most commonly facet data is retrieved from a query string variable via $_GET, however custom plugins can be written to retrieve data from the path as well. In addition to facet data retrieval, the url processor plugin is also responsible for building facet links and setting breadcrumb trails.

Each adapter instance is associated with a single url processor plugin. The plugin is associated with the adapter via hook_facetapi_searcher_info() implementations.

Hierarchy

• class \FacetapiUrlProcessor

File

plugins/facetapi/url_processor.inc, line 21

Base url processor plugin class.

abstract class FacetapiUrlProcessor {

  /**
   * The adapter that the url processor plugin is associated with.
   *
   * @var FacetapiAdapter
   */
  protected $adapter;

  /**
   * An array of facet params, usually $_GET.
   *
   * @var array.
   */
  protected $params = array();

  /**
   * The array key in FacetapiUrlProcessor::params containing the facet data.
   *
   * @var string
   */
  protected $filterKey = 'f';

  /**
   * Constructs a FacetapiUrlProcessor object.
   *
   * @param FacetapiAdapter $adapter
   *   The adapter that the url processor plugin is associated with.
   */
  public function __construct(FacetapiAdapter $adapter) {
    $this->adapter = $adapter;
  }

  /**
   * Fetches parameters from the source, usually $_GET.
   *
   * This method is invoked in FacetapiAdapter::__construct().
   *
   * @return array
   *   An associative array containing the params, usually $_GET.
   */
  public abstract function fetchParams();

  /**
   * Normalizes the array returned by FacetapiAdapter::fetchParams().
   *
   * When extracting data from a source such as $_GET, there are certain items
   * that you might nor want, for example the "q" or "page" keys. This method is
   * useful for filtering those out. In addition, plugins that do not get data
   * from $_GET can use this method to normalize the data into an associative
   * array that closely matches the data structure of $_GET.
   *
   * @param array $params
   *   An array of keyed params, usually as $_GET.
   * @param string $filter_key
   *   The array key in $params containing the facet data, defaults to "f".
   *
   * @return array
   *   An associative array containing the normalized params.
   */
  public abstract function normalizeParams(array $params, $filter_key = 'f');

  /**
   * Returns the query string variables for a facet item.
   *
   * The return array must be able to be passed as the "query" key of the
   * options array passed as the second argument to the url() function. See
   * http://api.drupal.org/api/drupal/includes%21common.inc/function/url/7 for
   * more details.
   *
   * @param array $facet
   *   The facet definition as returned by facetapi_facet_load().
   * @param array $values
   *   An array containing the item's values being added to or removed from the
   *   query string dependent on whether or not the item is active.
   * @param int $active
   *   An integer flagging whether the item is active or not. 1 if the item is
   *   active, 0 if it is not.
   *
   * @return array
   *   The query string variables.
   */
  public abstract function getQueryString(array $facet, array $values, $active);

  /**
   * Returns the path for a facet item.
   *
   * @param array $facet
   *   The facet definition.
   * @param array $values
   *   An array containing the item's values being added to or removed from the
   *   query string dependent on whether or not the item is active.
   * @param int $active
   *   An integer flagging whether the item is active or not.
   *
   * @return string
   *   The path of the facet.
   */
  public function getFacetPath(array $facet, array $values, $active) {
    return $this->adapter
      ->getSearchPath();
  }

  /**
   * Sets the breadcrumb trail for active searches.
   *
   * This method is called by FacetapiAdapter::processFacets(), which is called
   * directly by the backend to search the chain of Facet API events.
   */
  public abstract function setBreadcrumb();

  /**
   * Sets the normalized parameters.
   *
   * This method is usually called by FacetapiAdapter::setParams() and is very
   * rarely called directly.
   *
   * @param array $params
   *   An array of normalized params hat have already been passed through
   *   FacetapiUrlProcessor::normalizeParams().
   * @param string $filter_key
   *   The array key in $params containing the facet data, defaults to "f".
   *
   * @return FacetapiUrlParser
   *   An instance of this class.
   */
  public function setParams(array $params, $filter_key = 'f') {
    $this->params = $params;
    $this->filterKey = $filter_key;
    if (!isset($this->params[$this->filterKey]) || !is_array($this->params[$this->filterKey])) {
      $this->params[$this->filterKey] = array();
    }
    return $this;
  }

  /**
   * Returns the params.
   *
   * @return array
   *   An array containing the params.
   */
  public function getParams() {
    return $this->params;
  }

  /**
   * Removes an item from the $this->params array.
   *
   * @param int $pos
   *   The zero-based position of the value in the source data.
   */
  public function removeParam($pos) {
    unset($this->params[$this->filterKey][$pos]);
  }

  /**
   * Returns the filter key.
   *
   * @return string
   *   A string containing the filter key.
   */
  public function getFilterKey() {
    return $this->filterKey;
  }

  /**
   * Allows for processor specific overrides to the settings form.
   */
  public function settingsForm(&$form, &$form_state) {

    // Nothing to do...
  }

  /**
   * Provides default values for the backend specific settings.
   *
   * @return array
   *   The defaults keyed by setting name to value.
   */
  public function getDefaultSettings() {
    return array();
  }

}

Members

Name	Modifiers	Type	Description	Overrides
FacetapiUrlProcessor::$adapter	protected	property	The adapter that the url processor plugin is associated with.
FacetapiUrlProcessor::$filterKey	protected	property	The array key in FacetapiUrlProcessor::params containing the facet data.
FacetapiUrlProcessor::$params	protected	property	An array of facet params, usually $_GET.
FacetapiUrlProcessor::fetchParams	abstract public	function	Fetches parameters from the source, usually $_GET.	1
FacetapiUrlProcessor::getDefaultSettings	public	function	Provides default values for the backend specific settings.	1
FacetapiUrlProcessor::getFacetPath	public	function	Returns the path for a facet item.
FacetapiUrlProcessor::getFilterKey	public	function	Returns the filter key.
FacetapiUrlProcessor::getParams	public	function	Returns the params.
FacetapiUrlProcessor::getQueryString	abstract public	function	Returns the query string variables for a facet item.	1
FacetapiUrlProcessor::normalizeParams	abstract public	function	Normalizes the array returned by FacetapiAdapter::fetchParams().	1
FacetapiUrlProcessor::removeParam	public	function	Removes an item from the $this->params array.
FacetapiUrlProcessor::setBreadcrumb	abstract public	function	Sets the breadcrumb trail for active searches.	1
FacetapiUrlProcessor::setParams	public	function	Sets the normalized parameters.
FacetapiUrlProcessor::settingsForm	public	function	Allows for processor specific overrides to the settings form.	1
FacetapiUrlProcessor::__construct	public	function	Constructs a FacetapiUrlProcessor object.