Drupal example source code file (cache.inc)

This example Drupal source code file (cache.inc) is included in the DevDaily.com "Drupal Source Code Warehouse" project. The intent of this project is to help you "Learn Drupal by Example".

PHP - Drupal tags/keywords

array, cache, false, foreach, function, if, isset, name, php, reset, return, true, type, variable

The cache.inc Drupal example source code

<?php
// $Id: cache.inc,v 1.25.4.8 2010/10/26 19:06:26 dereine Exp $
/**
 * @file cache.inc
 *
 * Functions to load Views' data so that it knows what is available to
 * build queries from.
 */

/**
 * Load views files on behalf of modules.
 */
function _views_include_handlers() {
  views_module_include('views.inc');
}

/**
 * Load default views files on behalf of modules.
 */
function _views_include_default_views() {
  views_module_include('views_default.inc');
}

/**
 * Fetch Views' data from the cache
 */
function _views_fetch_data($table = NULL, $reset = FALSE) {
  static $cache = NULL;
  if (!isset($cache) || $reset) {
    $start = microtime(TRUE);
    // NOTE: This happens whether we retrieve them from cache or otherwise.

    $data = views_cache_get('views_data', TRUE);
    if (!empty($data->data)) {
      $cache = $data->data;
    }

    if (empty($cache)) {
      views_include_handlers();
      $cache = module_invoke_all('views_data');
      foreach (module_implements('views_data_alter') as $module) {
        $function = $module . '_views_data_alter';
        $function($cache);
      }

      views_cache_set('views_data', $cache, TRUE);
    }
  }

  if (!$table) {
    return $cache;
  }
  if (isset($cache[$table])) {
    return $cache[$table];
  }

  // Return an empty array if there is no match.
  return array();
}

/**
 * Fetch the plugin data from cache.
 */
function _views_fetch_plugin_data($type = NULL, $plugin = NULL, $reset = FALSE) {
  static $cache = NULL;
  if (!isset($cache) || $reset) {
    $start = microtime(TRUE);
    views_include('plugins');
    views_include_handlers();

    $cache = views_discover_plugins();

  }

  if (!$type && !$plugin) {
    return $cache;
  }
  elseif (!$plugin) {
    // Not in the if above so the else below won't run
    if (isset($cache[$type])) {
      return $cache[$type];
    }
  }
  elseif (isset($cache[$type][$plugin])) {
    return $cache[$type][$plugin];
  }

  // Return an empty array if there is no match.
  return array();
}

/**
 * Scan all modules for default views and rebuild the default views cache.
 *
 * @return An associative array of all known default views.
 */
function _views_discover_default_views($reset = FALSE) {
  static $cache = NULL;

  if (!isset($cache) || $reset) {
    $index = views_cache_get('views_default_views_index', TRUE);

    // Retrieve each cached default view
    if (!$reset && isset($index->data) && is_array($index->data)) {
      $cache = array();
      foreach ($index->data as $view_name) {
        $data = views_cache_get('views_default:' . $view_name, TRUE);
        if (isset($data->data) && is_object($data->data)) {
          $cache[$view_name] = $data->data;
        }
      }
    }
    // If missing index, rebuild the cache
    else {
      views_include_default_views();
      $cache = array();

      foreach (module_implements('views_default_views') as $module) {
        $results = call_user_func($module . "_views_default_views");
        if (!empty($results) && is_array($results)) {
          foreach($results as $name => $view) {
            // Only views with a sufficiently high api version are eligible.
            if (!empty($view->api_version) && $view->api_version >= 2) {
              // Do not cache dead handlers.
              $view->destroy();
              if (!isset($cache[$name])) {
                $cache[$name] = $view;
              }
              else {
                watchdog('view', "View name '@name' is already taken", array('@name' => $name), WATCHDOG_ERROR);
              }
            }
          }
        }
      }

      // Allow modules to modify default views before they are cached.
      drupal_alter('views_default_views', $cache);

      // Cache the index
      $index = array_keys($cache);
      views_cache_set('views_default_views_index', $index, TRUE);

      // Cache each view
      foreach ($cache as $name => $view) {
        views_cache_set('views_default:' . $name, $view, TRUE);
      }
    }
  }

  return $cache;
}

/**
 * Set a cached item in the views cache.
 *
 * This is just a convenience wrapper around cache_set().
 *
 * @param $cid
 *   The cache ID of the data to store.
 * @param $data
 *   The data to store in the cache. Complex data types will be automatically serialized before insertion.
 *   Strings will be stored as plain text and not serialized.
 * @param $use_language
 *   If TRUE, the data will be cached specific to the currently active language.
 */
function views_cache_set($cid, $data, $use_language = FALSE) {
  global $language;

  if (variable_get('views_skip_cache', FALSE)) {
    return;
  }
  if ($use_language) {
    $cid .= ':' . $language->language;
  }

  cache_set($cid, $data, 'cache_views');
}

/**
 * Return data from the persistent views cache.
 *
 * This is just a convenience wrapper around cache_get().
 *
 * @param $cid
 *   The cache ID of the data to retrieve.
 * @param $use_language
 *   If TRUE, the data will be requested specific to the currently active language.
 */
function views_cache_get($cid, $use_language = FALSE) {
  global $language;

  if (variable_get('views_skip_cache', FALSE)) {
    return 0;
  }
  if ($use_language) {
    $cid .= ':' . $language->language;
  }

  return cache_get($cid, 'cache_views');
}