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Drupal example source code file (aggregator.module)

This example Drupal source code file (aggregator.module) 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

aggregator, arguments, array, case, directory, feed, feeds, file, from, function, if, items, title, where

The aggregator.module Drupal example source code

<?php
// $Id: aggregator.module,v 1.374.2.6 2010/05/28 16:06:59 goba Exp $

/**
 * @file
 * Used to aggregate syndicated content (RSS, RDF, and Atom).
 */

/**
 * Implementation of hook_help().
 */
function aggregator_help($path, $arg) {
  switch ($path) {
    case 'admin/help#aggregator':
      $output = '<p>'. t('The aggregator is a powerful on-site syndicator and news reader that gathers fresh content from RSS-, RDF-, and Atom-based feeds made available across the web. Thousands of sites (particularly news sites and blogs) publish their latest headlines and posts in feeds, using a number of standardized XML-based formats. Formats supported by the aggregator include <a href="@rss">RSS</a>, <a href="@rdf">RDF</a>, and <a href="@atom">Atom</a>.', array('@rss' => 'http://cyber.law.harvard.edu/rss/', '@rdf' => 'http://www.w3.org/RDF/', '@atom' => 'http://www.atomenabled.org')) .'</p>';
      $output .= '<p>'. t('Feeds contain feed items, or individual posts published by the site providing the feed. Feeds may be grouped in categories, generally by topic. Users view feed items in the <a href="@aggregator">main aggregator display</a> or by <a href="@aggregator-sources">their source</a>. Administrators can <a href="@feededit">add, edit and delete feeds</a> and choose how often to check each feed for newly updated items. The most recent items in either a feed or category can be displayed as a block through the <a href="@admin-block">blocks administration page</a>. A <a href="@aggregator-opml">machine-readable OPML file</a> of all feeds is available. A correctly configured <a href="@cron">cron maintenance task</a> is required to update feeds automatically.', array('@aggregator' => url('aggregator'), '@aggregator-sources' => url('aggregator/sources'), '@feededit' => url('admin/content/aggregator'), '@admin-block' => url('admin/build/block'), '@aggregator-opml' => url('aggregator/opml'), '@cron' => url('admin/reports/status'))) .'</p>';
      $output .= '<p>'. t('For more information, see the online handbook entry for <a href="@aggregator">Aggregator module</a>.', array('@aggregator' => 'http://drupal.org/handbook/modules/aggregator/')) .'</p>';
      return $output;
    case 'admin/content/aggregator':
      $output = '<p>'. t('Thousands of sites (particularly news sites and blogs) publish their latest headlines and posts in feeds, using a number of standardized XML-based formats. Formats supported by the aggregator include <a href="@rss">RSS</a>, <a href="@rdf">RDF</a>, and <a href="@atom">Atom</a>.', array('@rss' => 'http://cyber.law.harvard.edu/rss/', '@rdf' => 'http://www.w3.org/RDF/', '@atom' => 'http://www.atomenabled.org')) .'</p>';
      $output .= '<p>'. t('Current feeds are listed below, and <a href="@addfeed">new feeds may be added</a>. For each feed or feed category, the <em>latest items</em> block may be enabled at the <a href="@block">blocks administration page</a>.', array('@addfeed' => url('admin/content/aggregator/add/feed'), '@block' => url('admin/build/block'))) .'</p>';
      return $output;
    case 'admin/content/aggregator/add/feed':
      return '<p>'. t('Add a feed in RSS, RDF or Atom format. A feed may only have one entry.') .'</p>';
    case 'admin/content/aggregator/add/category':
      return '<p>'. t('Categories allow feed items from different feeds to be grouped together. For example, several sport-related feeds may belong to a category named <em>Sports</em>. Feed items may be grouped automatically (by selecting a category when creating or editing a feed) or manually (via the <em>Categorize</em> page available from feed item listings). Each category provides its own feed page and block.') .'</p>';
  }
}

/**
 * Implementation of hook_theme()
 */
function aggregator_theme() {
  return array(
    'aggregator_wrapper' => array(
      'arguments' => array('content' => NULL),
      'file' => 'aggregator.pages.inc',
      'template' => 'aggregator-wrapper',
    ),
    'aggregator_categorize_items' => array(
      'arguments' => array('form' => NULL),
      'file' => 'aggregator.pages.inc',
    ),
    'aggregator_feed_source' => array(
      'arguments' => array('feed' => NULL),
      'file' => 'aggregator.pages.inc',
      'template' => 'aggregator-feed-source',
    ),
    'aggregator_block_item' => array(
      'arguments' => array('item' => NULL, 'feed' => 0),
    ),
    'aggregator_summary_items' => array(
      'arguments' => array('summary_items' => NULL, 'source' => NULL),
      'file' => 'aggregator.pages.inc',
      'template' => 'aggregator-summary-items',
    ),
    'aggregator_summary_item' => array(
      'arguments' => array('item' => NULL),
      'file' => 'aggregator.pages.inc',
      'template' => 'aggregator-summary-item',
    ),
    'aggregator_item' => array(
      'arguments' => array('item' => NULL),
      'file' => 'aggregator.pages.inc',
      'template' => 'aggregator-item',
    ),
    'aggregator_page_opml' => array(
      'arguments' => array('feeds' => NULL),
      'file' => 'aggregator.pages.inc',
    ),
    'aggregator_page_rss' => array(
      'arguments' => array('feeds' => NULL, 'category' => NULL),
      'file' => 'aggregator.pages.inc',
    ),
  );
}

/**
 * Implementation of hook_menu().
 */
function aggregator_menu() {
  $items['admin/content/aggregator'] = array(
    'title' => 'Feed aggregator',
    'description' => "Configure which content your site aggregates from other sites, how often it polls them, and how they're categorized.",
    'page callback' => 'aggregator_admin_overview',
    'access arguments' => array('administer news feeds'),
    'file' => 'aggregator.admin.inc',
  );
  $items['admin/content/aggregator/add/feed'] = array(
    'title' => 'Add feed',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_form_feed'),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_LOCAL_TASK,
    'parent' => 'admin/content/aggregator',
    'file' => 'aggregator.admin.inc',
  );
  $items['admin/content/aggregator/add/category'] = array(
    'title' => 'Add category',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_form_category'),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_LOCAL_TASK,
    'parent' => 'admin/content/aggregator',
    'file' => 'aggregator.admin.inc',
  );
  $items['admin/content/aggregator/remove/%aggregator_feed'] = array(
    'title' => 'Remove items',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_admin_remove_feed', 4),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_CALLBACK,
    'file' => 'aggregator.admin.inc',
  );
  $items['admin/content/aggregator/update/%aggregator_feed'] = array(
    'title' => 'Update items',
    'page callback' => 'aggregator_admin_refresh_feed',
    'page arguments' => array(4),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_CALLBACK,
    'file' => 'aggregator.admin.inc',
  );
  $items['admin/content/aggregator/list'] = array(
    'title' => 'List',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['admin/content/aggregator/settings'] = array(
    'title' => 'Settings',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_admin_settings'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 10,
    'access arguments' => array('administer news feeds'),
    'file' => 'aggregator.admin.inc',
  );
  $items['aggregator'] = array(
    'title' => 'Feed aggregator',
    'page callback' => 'aggregator_page_last',
    'access arguments' => array('access news feeds'),
    'weight' => 5,
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/sources'] = array(
    'title' => 'Sources',
    'page callback' => 'aggregator_page_sources',
    'access arguments' => array('access news feeds'),
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/categories'] = array(
    'title' => 'Categories',
    'page callback' => 'aggregator_page_categories',
    'access callback' => '_aggregator_has_categories',
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/rss'] = array(
    'title' => 'RSS feed',
    'page callback' => 'aggregator_page_rss',
    'access arguments' => array('access news feeds'),
    'type' => MENU_CALLBACK,
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/opml'] = array(
    'title' => 'OPML feed',
    'page callback' => 'aggregator_page_opml',
    'access arguments' => array('access news feeds'),
    'type' => MENU_CALLBACK,
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/categories/%aggregator_category'] = array(
    'title callback' => '_aggregator_category_title',
    'title arguments' => array(2),
    'page callback' => 'aggregator_page_category',
    'page arguments' => array(2),
    'access callback' => 'user_access',
    'access arguments' => array('access news feeds'),
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/categories/%aggregator_category/view'] = array(
    'title' => 'View',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['aggregator/categories/%aggregator_category/categorize'] = array(
    'title' => 'Categorize',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_page_category', 2),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_LOCAL_TASK,
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/categories/%aggregator_category/configure'] = array(
    'title' => 'Configure',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_form_category', 2),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 1,
    'file' => 'aggregator.admin.inc',
  );
  $items['aggregator/sources/%aggregator_feed'] = array(
    'page callback' => 'aggregator_page_source',
    'page arguments' => array(2),
    'access arguments' => array('access news feeds'),
    'type' => MENU_CALLBACK,
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/sources/%aggregator_feed/view'] = array(
    'title' => 'View',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['aggregator/sources/%aggregator_feed/categorize'] = array(
    'title' => 'Categorize',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_page_source', 2),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_LOCAL_TASK,
    'file' => 'aggregator.pages.inc',
  );
  $items['aggregator/sources/%aggregator_feed/configure'] = array(
    'title' => 'Configure',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_form_feed', 2),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 1,
    'file' => 'aggregator.admin.inc',
  );
  $items['admin/content/aggregator/edit/feed/%aggregator_feed'] = array(
    'title' => 'Edit feed',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_form_feed', 5),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_CALLBACK,
    'file' => 'aggregator.admin.inc',
  );
  $items['admin/content/aggregator/edit/category/%aggregator_category'] = array(
    'title' => 'Edit category',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('aggregator_form_category', 5),
    'access arguments' => array('administer news feeds'),
    'type' => MENU_CALLBACK,
    'file' => 'aggregator.admin.inc',
  );

  return $items;
}

/**
 * Menu callback.
 *
 * @return
 *   An aggregator category title.
 */
function _aggregator_category_title($category) {
  return $category['title'];
}

/**
 * Implementation of hook_init().
 */
function aggregator_init() {
  drupal_add_css(drupal_get_path('module', 'aggregator') .'/aggregator.css');
}

/**
 * Find out whether there are any aggregator categories.
 *
 * @return
 *   TRUE if there is at least one category and the user has access to them, FALSE otherwise.
 */
function _aggregator_has_categories() {
  return user_access('access news feeds') && db_result(db_query('SELECT COUNT(*) FROM {aggregator_category}'));
}

/**
 * Implementation of hook_perm().
 */
function aggregator_perm() {
  return array('administer news feeds', 'access news feeds');
}

/**
 * Implementation of hook_cron().
 *
 * Checks news feeds for updates once their refresh interval has elapsed.
 */
function aggregator_cron() {
  $result = db_query('SELECT * FROM {aggregator_feed} WHERE checked + refresh < %d', time());
  while ($feed = db_fetch_array($result)) {
    aggregator_refresh($feed);
  }
}

/**
 * Implementation of hook_block().
 *
 * Generates blocks for the latest news items in each category and feed.
 */
function aggregator_block($op = 'list', $delta = 0, $edit = array()) {
  if (user_access('access news feeds')) {
    if ($op == 'list') {
      $result = db_query('SELECT cid, title FROM {aggregator_category} ORDER BY title');
      while ($category = db_fetch_object($result)) {
        $block['category-'. $category->cid]['info'] = t('!title category latest items', array('!title' => $category->title));
      }
      $result = db_query('SELECT fid, title FROM {aggregator_feed} ORDER BY fid');
      while ($feed = db_fetch_object($result)) {
        $block['feed-'. $feed->fid]['info'] = t('!title feed latest items', array('!title' => $feed->title));
      }
    }
    else if ($op == 'configure') {
      list($type, $id) = explode('-', $delta);
      if ($type == 'category') {
        $value = db_result(db_query('SELECT block FROM {aggregator_category} WHERE cid = %d', $id));
      }
      else {
        $value = db_result(db_query('SELECT block FROM {aggregator_feed} WHERE fid = %d', $id));
      }
      $form['block'] = array('#type' => 'select', '#title' => t('Number of news items in block'), '#default_value' => $value, '#options' => drupal_map_assoc(array(2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)));
      return $form;
    }
    else if ($op == 'save') {
      list($type, $id) = explode('-', $delta);
      if ($type == 'category') {
        $value = db_query('UPDATE {aggregator_category} SET block = %d WHERE cid = %d', $edit['block'], $id);
      }
      else {
        $value = db_query('UPDATE {aggregator_feed} SET block = %d WHERE fid = %d', $edit['block'], $id);
      }
    }
    else if ($op == 'view') {
      list($type, $id) = explode('-', $delta);
      switch ($type) {
        case 'feed':
          if ($feed = db_fetch_object(db_query('SELECT fid, title, block FROM {aggregator_feed} WHERE fid = %d', $id))) {
            $block['subject'] = check_plain($feed->title);
            $result = db_query_range('SELECT * FROM {aggregator_item} WHERE fid = %d ORDER BY timestamp DESC, iid DESC', $feed->fid, 0, $feed->block);
            $read_more = theme('more_link', url('aggregator/sources/'. $feed->fid), t("View this feed's recent news."));
          }
          break;

        case 'category':
          if ($category = db_fetch_object(db_query('SELECT cid, title, block FROM {aggregator_category} WHERE cid = %d', $id))) {
            $block['subject'] = check_plain($category->title);
            $result = db_query_range('SELECT i.* FROM {aggregator_category_item} ci LEFT JOIN {aggregator_item} i ON ci.iid = i.iid WHERE ci.cid = %d ORDER BY i.timestamp DESC, i.iid DESC', $category->cid, 0, $category->block);
            $read_more = theme('more_link', url('aggregator/categories/'. $category->cid), t("View this category's recent news."));
          }
          break;
      }
      $items = array();
      while ($item = db_fetch_object($result)) {
        $items[] = theme('aggregator_block_item', $item);
      }

      // Only display the block if there are items to show.
      if (count($items) > 0) {
        $block['content'] = theme('item_list', $items) . $read_more;
      }
    }
    if (isset($block)) {
      return $block;
    }
  }
}

/**
 * Add/edit/delete aggregator categories.
 *
 * @param $edit
 *   An associative array describing the category to be added/edited/deleted.
 */
function aggregator_save_category($edit) {
  $link_path = 'aggregator/categories/';
  if (!empty($edit['cid'])) {
    $link_path .= $edit['cid'];
    if (!empty($edit['title'])) {
      db_query("UPDATE {aggregator_category} SET title = '%s', description = '%s' WHERE cid = %d", $edit['title'], $edit['description'], $edit['cid']);
      $op = 'update';
    }
    else {
      db_query('DELETE FROM {aggregator_category} WHERE cid = %d', $edit['cid']);
      // Make sure there is no active block for this category.
      db_query("DELETE FROM {blocks} WHERE module = '%s' AND delta = '%s'", 'aggregator', 'category-' . $edit['cid']);
      $edit['title'] = '';
      $op = 'delete';
    }
  }
  else if (!empty($edit['title'])) {
    // A single unique id for bundles and feeds, to use in blocks
    db_query("INSERT INTO {aggregator_category} (title, description, block) VALUES ('%s', '%s', 5)", $edit['title'], $edit['description']);
    $link_path .= db_last_insert_id('aggregator_category', 'cid');
    $op = 'insert';
  }
  if (isset($op)) {
    menu_link_maintain('aggregator', $op, $link_path, $edit['title']);
  }
}

/**
 * Add/edit/delete an aggregator feed.
 *
 * @param $edit
 *   An associative array describing the feed to be added/edited/deleted.
 */
function aggregator_save_feed($edit) {
  if (!empty($edit['fid'])) {
    // An existing feed is being modified, delete the category listings.
    db_query('DELETE FROM {aggregator_category_feed} WHERE fid = %d', $edit['fid']);
  }
  if (!empty($edit['fid']) && !empty($edit['title'])) {
    db_query("UPDATE {aggregator_feed} SET title = '%s', url = '%s', refresh = %d WHERE fid = %d", $edit['title'], $edit['url'], $edit['refresh'], $edit['fid']);
  }
  else if (!empty($edit['fid'])) {
    $items = array();
    $result = db_query('SELECT iid FROM {aggregator_item} WHERE fid = %d', $edit['fid']);
    while ($item = db_fetch_object($result)) {
      $items[] = "iid = $item->iid";
    }
    if (!empty($items)) {
      db_query('DELETE FROM {aggregator_category_item} WHERE '. implode(' OR ', $items));
    }
    db_query('DELETE FROM {aggregator_feed} WHERE fid = %d', $edit['fid']);
    db_query('DELETE FROM {aggregator_item} WHERE fid = %d', $edit['fid']);
    // Make sure there is no active block for this feed.
    db_query("DELETE FROM {blocks} WHERE module = '%s' AND delta = '%s'", 'aggregator', 'feed-' . $edit['fid']);
  }
  else if (!empty($edit['title'])) {
    db_query("INSERT INTO {aggregator_feed} (title, url, refresh, block, description, image) VALUES ('%s', '%s', %d, 5, '', '')", $edit['title'], $edit['url'], $edit['refresh']);
    // A single unique id for bundles and feeds, to use in blocks.
    $edit['fid'] = db_last_insert_id('aggregator_feed', 'fid');
  }
  if (!empty($edit['title'])) {
    // The feed is being saved, save the categories as well.
    if (!empty($edit['category'])) {
      foreach ($edit['category'] as $cid => $value) {
        if ($value) {
          db_query('INSERT INTO {aggregator_category_feed} (fid, cid) VALUES (%d, %d)', $edit['fid'], $cid);
        }
      }
    }
  }
}

/**
 * Removes all items from a feed.
 *
 * @param $feed
 *   An associative array describing the feed to be cleared.
 */
function aggregator_remove($feed) {
  $result = db_query('SELECT iid FROM {aggregator_item} WHERE fid = %d', $feed['fid']);
  while ($item = db_fetch_object($result)) {
    $items[] = "iid = $item->iid";
  }
  if (!empty($items)) {
    db_query('DELETE FROM {aggregator_category_item} WHERE '. implode(' OR ', $items));
  }
  db_query('DELETE FROM {aggregator_item} WHERE fid = %d', $feed['fid']);
  db_query("UPDATE {aggregator_feed} SET checked = 0, etag = '', modified = 0 WHERE fid = %d", $feed['fid']);
  drupal_set_message(t('The news items from %site have been removed.', array('%site' => $feed['title'])));
}

/**
 * Call-back function used by the XML parser.
 */
function aggregator_element_start($parser, $name, $attributes) {
  global $item, $element, $tag, $items, $channel;

  switch ($name) {
    case 'IMAGE':
    case 'TEXTINPUT':
    case 'CONTENT':
    case 'SUMMARY':
    case 'TAGLINE':
    case 'SUBTITLE':
    case 'LOGO':
    case 'INFO':
      $element = $name;
      break;
    case 'ID':
      if ($element != 'ITEM') {
        $element = $name;
      }
    case 'LINK':
      if (!empty($attributes['REL']) && $attributes['REL'] == 'alternate') {
        if ($element == 'ITEM') {
          $items[$item]['LINK'] = $attributes['HREF'];
        }
        else {
          $channel['LINK'] = $attributes['HREF'];
        }
      }
      break;
    case 'ITEM':
      $element = $name;
      $item += 1;
      break;
    case 'ENTRY':
      $element = 'ITEM';
      $item += 1;
      break;
  }

  $tag = $name;
}

/**
 * Call-back function used by the XML parser.
 */
function aggregator_element_end($parser, $name) {
  global $element;

  switch ($name) {
    case 'IMAGE':
    case 'TEXTINPUT':
    case 'ITEM':
    case 'ENTRY':
    case 'CONTENT':
    case 'INFO':
      $element = '';
      break;
    case 'ID':
      if ($element == 'ID') {
        $element = '';
      }
  }
}

/**
 * Call-back function used by the XML parser.
 */
function aggregator_element_data($parser, $data) {
  global $channel, $element, $items, $item, $image, $tag;
  $items += array($item => array());
  switch ($element) {
    case 'ITEM':
      $items[$item] += array($tag => '');
      $items[$item][$tag] .= $data;
      break;
    case 'IMAGE':
    case 'LOGO':
      $image += array($tag => '');
      $image[$tag] .= $data;
      break;
    case 'LINK':
      if ($data) {
        $items[$item] += array($tag => '');
        $items[$item][$tag] .= $data;
      }
      break;
    case 'CONTENT':
      $items[$item] += array('CONTENT' => '');
      $items[$item]['CONTENT'] .= $data;
      break;
    case 'SUMMARY':
      $items[$item] += array('SUMMARY' => '');
      $items[$item]['SUMMARY'] .= $data;
      break;
    case 'TAGLINE':
    case 'SUBTITLE':
      $channel += array('DESCRIPTION' => '');
      $channel['DESCRIPTION'] .= $data;
      break;
    case 'INFO':
    case 'ID':
    case 'TEXTINPUT':
      // The sub-element is not supported. However, we must recognize
      // it or its contents will end up in the item array.
      break;
    default:
      $channel += array($tag => '');
      $channel[$tag] .= $data;
  }
}

/**
 * Checks a news feed for new items.
 *
 * @param $feed
 *   An associative array describing the feed to be refreshed.
 */
function aggregator_refresh($feed) {
  global $channel, $image;

  // Generate conditional GET headers.
  $headers = array();
  if ($feed['etag']) {
    $headers['If-None-Match'] = $feed['etag'];
  }
  if ($feed['modified']) {
    $headers['If-Modified-Since'] = gmdate('D, d M Y H:i:s', $feed['modified']) .' GMT';
  }

  // Request feed.
  $result = drupal_http_request($feed['url'], $headers);

  // Process HTTP response code.
  switch ($result->code) {
    case 304:
      db_query('UPDATE {aggregator_feed} SET checked = %d WHERE fid = %d', time(), $feed['fid']);
      drupal_set_message(t('There is no new syndicated content from %site.', array('%site' => $feed['title'])));
      break;
    case 301:
      $feed['url'] = $result->redirect_url;
      watchdog('aggregator', 'Updated URL for feed %title to %url.', array('%title' => $feed['title'], '%url' => $feed['url']));
      // Deliberate no break.
    case 200:
    case 302:
    case 307:
      // Filter the input data:
      if (aggregator_parse_feed($result->data, $feed)) {
        $modified = empty($result->headers['Last-Modified']) ? 0 : strtotime($result->headers['Last-Modified']);

        // Prepare the channel data.
        foreach ($channel as $key => $value) {
          $channel[$key] = trim($value);
        }

        // Prepare the image data (if any).
        foreach ($image as $key => $value) {
          $image[$key] = trim($value);
        }

        if (!empty($image['LINK']) && !empty($image['URL']) && !empty($image['TITLE'])) {
          // Note, we should really use theme_image() here but that only works with local images it won't work with images fetched with a URL unless PHP version > 5
          $image = '<a href="'. check_url($image['LINK']) .'" class="feed-image"><img src="'. check_url($image['URL']) .'" alt="'. check_plain($image['TITLE']) .'" /></a>';
        }
        else {
          $image = NULL;
        }

        $etag = empty($result->headers['ETag']) ? '' : $result->headers['ETag'];
        // Update the feed data.
        db_query("UPDATE {aggregator_feed} SET url = '%s', checked = %d, link = '%s', description = '%s', image = '%s', etag = '%s', modified = %d WHERE fid = %d", $feed['url'], time(), $channel['LINK'], $channel['DESCRIPTION'], $image, $etag, $modified, $feed['fid']);

        // Clear the cache.
        cache_clear_all();

        watchdog('aggregator', 'There is new syndicated content from %site.', array('%site' => $feed['title']));
        drupal_set_message(t('There is new syndicated content from %site.', array('%site' => $feed['title'])));
      }
      break;
    default:
      watchdog('aggregator', 'The feed from %site seems to be broken, due to "%error".', array('%site' => $feed['title'], '%error' => $result->code .' '. $result->error), WATCHDOG_WARNING);
      drupal_set_message(t('The feed from %site seems to be broken, because of error "%error".', array('%site' => $feed['title'], '%error' => $result->code .' '. $result->error)));
  }
}

/**
 * Parse the W3C date/time format, a subset of ISO 8601. PHP date parsing
 * functions do not handle this format.
 * See http://www.w3.org/TR/NOTE-datetime for more information.
 * Originally from MagpieRSS (http://magpierss.sourceforge.net/).
 *
 * @param $date_str
 *   A string with a potentially W3C DTF date.
 * @return
 *   A timestamp if parsed successfully or FALSE if not.
 */
function aggregator_parse_w3cdtf($date_str) {
  if (preg_match('/(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2})(:(\d{2}))?(?:([-+])(\d{2}):?(\d{2})|(Z))?/', $date_str, $match)) {
    list($year, $month, $day, $hours, $minutes, $seconds) = array($match[1], $match[2], $match[3], $match[4], $match[5], $match[6]);
    // calc epoch for current date assuming GMT
    $epoch = gmmktime($hours, $minutes, $seconds, $month, $day, $year);
    if ($match[10] != 'Z') { // Z is zulu time, aka GMT
      list($tz_mod, $tz_hour, $tz_min) = array($match[8], $match[9], $match[10]);
      // zero out the variables
      if (!$tz_hour) {
        $tz_hour = 0;
      }
      if (!$tz_min) {
        $tz_min = 0;
      }
      $offset_secs = (($tz_hour * 60) + $tz_min) * 60;
      // is timezone ahead of GMT?  then subtract offset
      if ($tz_mod == '+') {
        $offset_secs *= -1;
      }
      $epoch += $offset_secs;
    }
    return $epoch;
  }
  else {
    return FALSE;
  }
}

/**
 * Parse a feed and store its items.
 *
 * @param $data
 *   The feed data.
 * @param $feed
 *   An associative array describing the feed to be parsed.
 * @return
 *   0 on error, 1 otherwise.
 */
function aggregator_parse_feed(&$data, $feed) {
  global $items, $image, $channel;

  // Unset the global variables before we use them:
  unset($GLOBALS['element'], $GLOBALS['item'], $GLOBALS['tag']);
  $items = array();
  $image = array();
  $channel = array();

  // parse the data:
  $xml_parser = drupal_xml_parser_create($data);
  xml_set_element_handler($xml_parser, 'aggregator_element_start', 'aggregator_element_end');
  xml_set_character_data_handler($xml_parser, 'aggregator_element_data');

  if (!xml_parse($xml_parser, $data, 1)) {
    watchdog('aggregator', 'The feed from %site seems to be broken, due to an error "%error" on line %line.', array('%site' => $feed['title'], '%error' => xml_error_string(xml_get_error_code($xml_parser)), '%line' => xml_get_current_line_number($xml_parser)), WATCHDOG_WARNING);
    drupal_set_message(t('The feed from %site seems to be broken, because of error "%error" on line %line.', array('%site' => $feed['title'], '%error' => xml_error_string(xml_get_error_code($xml_parser)), '%line' => xml_get_current_line_number($xml_parser))), 'error');
    return 0;
  }
  xml_parser_free($xml_parser);

  // We reverse the array such that we store the first item last, and the last
  // item first. In the database, the newest item should be at the top.
  $items = array_reverse($items);

  // Initialize variables.
  $title = $link = $author = $description = $guid = NULL;
  foreach ($items as $item) {
    unset($title, $link, $author, $description, $guid);

    // Prepare the item:
    foreach ($item as $key => $value) {
      $item[$key] = trim($value);
    }

    // Resolve the item's title. If no title is found, we use up to 40
    // characters of the description ending at a word boundary but not
    // splitting potential entities.
    if (!empty($item['TITLE'])) {
      $title = $item['TITLE'];
    }
    elseif (!empty($item['DESCRIPTION'])) {
      $title = preg_replace('/^(.*)[^\w;&].*?$/', "\\1", truncate_utf8($item['DESCRIPTION'], 40));
    }
    else {
      $title = '';
    }

    // Resolve the items link.
    if (!empty($item['LINK'])) {
      $link = $item['LINK'];
    }
    else {
      $link = $feed['link'];
    }
    $guid = isset($item['GUID']) ? $item['GUID'] : '';

    // Atom feeds have a CONTENT and/or SUMMARY tag instead of a DESCRIPTION tag.
    if (!empty($item['CONTENT:ENCODED'])) {
      $item['DESCRIPTION'] = $item['CONTENT:ENCODED'];
    }
    else if (!empty($item['SUMMARY'])) {
      $item['DESCRIPTION'] = $item['SUMMARY'];
    }
    else if (!empty($item['CONTENT'])) {
      $item['DESCRIPTION'] = $item['CONTENT'];
    }

    // Try to resolve and parse the item's publication date. If no date is
    // found, we use the current date instead.
    $date = 'now';
    foreach (array('PUBDATE', 'DC:DATE', 'DCTERMS:ISSUED', 'DCTERMS:CREATED', 'DCTERMS:MODIFIED', 'ISSUED', 'CREATED', 'MODIFIED', 'PUBLISHED', 'UPDATED') as $key) {
      if (!empty($item[$key])) {
        $date = $item[$key];
        break;
      }
    }

    $timestamp = strtotime($date); // As of PHP 5.1.0, strtotime returns FALSE on failure instead of -1.
    if ($timestamp <= 0) {
      $timestamp = aggregator_parse_w3cdtf($date); // Returns FALSE on failure
      if (!$timestamp) {
        $timestamp = time(); // better than nothing
      }
    }

    // Save this item. Try to avoid duplicate entries as much as possible. If
    // we find a duplicate entry, we resolve it and pass along its ID is such
    // that we can update it if needed.
    if (!empty($guid)) {
      $entry = db_fetch_object(db_query("SELECT iid FROM {aggregator_item} WHERE fid = %d AND guid = '%s'", $feed['fid'], $guid));
    }
    else if ($link && $link != $feed['link'] && $link != $feed['url']) {
      $entry = db_fetch_object(db_query("SELECT iid FROM {aggregator_item} WHERE fid = %d AND link = '%s'", $feed['fid'], $link));
    }
    else {
      $entry = db_fetch_object(db_query("SELECT iid FROM {aggregator_item} WHERE fid = %d AND title = '%s'", $feed['fid'], $title));
    }
    $item += array('AUTHOR' => '', 'DESCRIPTION' => '');
    aggregator_save_item(array('iid' => (isset($entry->iid) ? $entry->iid:  ''), 'fid' => $feed['fid'], 'timestamp' => $timestamp, 'title' => $title, 'link' => $link, 'author' => $item['AUTHOR'], 'description' => $item['DESCRIPTION'], 'guid' => $guid));
  }

  // Remove all items that are older than flush item timer.
  $age = time() - variable_get('aggregator_clear', 9676800);
  $result = db_query('SELECT iid FROM {aggregator_item} WHERE fid = %d AND timestamp < %d', $feed['fid'], $age);

  $items = array();
  $num_rows = FALSE;
  while ($item = db_fetch_object($result)) {
    $items[] = $item->iid;
    $num_rows = TRUE;
  }
  if ($num_rows) {
    db_query('DELETE FROM {aggregator_category_item} WHERE iid IN ('. implode(', ', $items) .')');
    db_query('DELETE FROM {aggregator_item} WHERE fid = %d AND timestamp < %d', $feed['fid'], $age);
  }

  return 1;
}

/**
 * Add/edit/delete an aggregator item.
 *
 * @param $edit
 *   An associative array describing the item to be added/edited/deleted.
 */
function aggregator_save_item($edit) {
  if ($edit['iid'] && $edit['title']) {
    db_query("UPDATE {aggregator_item} SET title = '%s', link = '%s', author = '%s', description = '%s', guid = '%s', timestamp = %d WHERE iid = %d", $edit['title'], $edit['link'], $edit['author'], $edit['description'], $edit['guid'], $edit['timestamp'], $edit['iid']);
  }
  else if ($edit['iid']) {
    db_query('DELETE FROM {aggregator_item} WHERE iid = %d', $edit['iid']);
    db_query('DELETE FROM {aggregator_category_item} WHERE iid = %d', $edit['iid']);
  }
  else if ($edit['title'] && $edit['link']) {
    db_query("INSERT INTO {aggregator_item} (fid, title, link, author, description, timestamp, guid) VALUES (%d, '%s', '%s', '%s', '%s', %d, '%s')", $edit['fid'], $edit['title'], $edit['link'], $edit['author'], $edit['description'], $edit['timestamp'], $edit['guid']);
    $edit['iid'] = db_last_insert_id('aggregator_item', 'iid');
    // file the items in the categories indicated by the feed
    $categories = db_query('SELECT cid FROM {aggregator_category_feed} WHERE fid = %d', $edit['fid']);
    while ($category = db_fetch_object($categories)) {
      db_query('INSERT INTO {aggregator_category_item} (cid, iid) VALUES (%d, %d)', $category->cid, $edit['iid']);
    }
  }
}

/**
 * Load an aggregator feed.
 *
 * @param $fid
 *   The feed id.
 * @return
 *   An associative array describing the feed.
 */
function aggregator_feed_load($fid) {
  static $feeds;
  if (!isset($feeds[$fid])) {
    $feeds[$fid] = db_fetch_array(db_query('SELECT * FROM {aggregator_feed} WHERE fid = %d', $fid));
  }
  return $feeds[$fid];
}

/**
 * Load an aggregator category.
 *
 * @param $cid
 *   The category id.
 * @return
 *   An associative array describing the category.
 */
function aggregator_category_load($cid) {
  static $categories;
  if (!isset($categories[$cid])) {
    $categories[$cid] = db_fetch_array(db_query('SELECT * FROM {aggregator_category} WHERE cid = %d', $cid));
  }
  return $categories[$cid];
}

/**
 * Format an individual feed item for display in the block.
 *
 * @param $item
 *   The item to be displayed.
 * @param $feed
 *   Not used.
 * @return
 *   The item HTML.
 * @ingroup themeable
 */
function theme_aggregator_block_item($item, $feed = 0) {
  global $user;

  $output = '';
  if ($user->uid && module_exists('blog') && user_access('create blog entries')) {
    if ($image = theme('image', 'misc/blog.png', t('blog it'), t('blog it'))) {
      $output .= '<div class="icon">'. l($image, 'node/add/blog', array('attributes' => array('title' => t('Comment on this news item in your personal blog.'), 'class' => 'blog-it'), 'query' => "iid=$item->iid", 'html' => TRUE)) .'</div>';
    }
  }

  // Display the external link to the item.
  $output .= '<a href="'. check_url($item->link) .'">'. check_plain($item->title) ."</a>\n";

  return $output;
}

/**
 * Safely render HTML content, as allowed.
 *
 * @param $value
 *   The content to be filtered.
 * @return
 *   The filtered content.
 */
function aggregator_filter_xss($value) {
  return filter_xss($value, preg_split('/\s+|<|>/', variable_get('aggregator_allowed_html_tags', '<a> <b> <br> <dd> <dl> <dt> <em> <i> <li> <ol> <p> <strong> <u> <ul>'), -1, PREG_SPLIT_NO_EMPTY));
}

/**
 * Helper function for drupal_map_assoc.
 *
 * @param $count
 *   Items count.
 * @return
 *   Plural-formatted "@count items"
 */
function _aggregator_items($count) {
  return format_plural($count, '1 item', '@count items');
}

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