plugins/pubsubhubbub/pubsubhubbub.php

   1 <?php
   2
   3 /**
   4  * PubSubHubbub plugin.
   5  *
   6  * PubSub is a protocol which fasten up RSS fetching:
   7  *   - Every time a new link is posted, Shaarli notify the hub.
   8  *   - The hub notify all feed subscribers that a new link has been posted.
   9  *   - Subscribers retrieve the new link.
  10  */
  11
  12 use pubsubhubbub\publisher\Publisher;
  13 use Shaarli\Config\ConfigManager;
  14
  15 /**
  16  * Plugin init function - set the hub to the default appspot one.
  17  *
  18  * @param ConfigManager $conf instance.
  19  */
  20 function pubsubhubbub_init($conf)
  21 {
  22     $hub = $conf->get('plugins.PUBSUBHUB_URL');
  23     if (empty($hub)) {
  24         // Default hub.
  25         $conf->set('plugins.PUBSUBHUB_URL', 'https://pubsubhubbub.appspot.com/');
  26     }
  27 }
  28
  29
  30 /**
  31  * Render feed hook.
  32  * Adds the hub URL in ATOM and RSS feed.
  33  *
  34  * @param array         $data Template data.
  35  * @param ConfigManager $conf instance.
  36  *
  37  * @return array updated template data.
  38  */
  39 function hook_pubsubhubbub_render_feed($data, $conf)
  40 {
  41     $feedType = $data['_PAGE_'] == Router::$PAGE_FEED_RSS ? FeedBuilder::$FEED_RSS : FeedBuilder::$FEED_ATOM;
  42     $template = file_get_contents(PluginManager::$PLUGINS_PATH . '/pubsubhubbub/hub.'. $feedType .'.xml');
  43     $data['feed_plugins_header'][] = sprintf($template, $conf->get('plugins.PUBSUBHUB_URL'));
  44
  45     return $data;
  46 }
  47
  48 /**
  49  * Save link hook.
  50  * Publish to the hub when a link is saved.
  51  *
  52  * @param array         $data Template data.
  53  * @param ConfigManager $conf instance.
  54  *
  55  * @return array unaltered data.
  56  */
  57 function hook_pubsubhubbub_save_link($data, $conf)
  58 {
  59     $feeds = array(
  60         index_url($_SERVER) .'?do=atom',
  61         index_url($_SERVER) .'?do=rss',
  62     );
  63
  64     $httpPost = function_exists('curl_version') ? false : 'nocurl_http_post';
  65     try {
  66         $p = new Publisher($conf->get('plugins.PUBSUBHUB_URL'));
  67         $p->publish_update($feeds, $httpPost);
  68     } catch (Exception $e) {
  69         error_log(sprintf(t('Could not publish to PubSubHubbub: %s'), $e->getMessage()));
  70     }
  71
  72     return $data;
  73 }
  74
  75 /**
  76  * Http function used to post to the hub endpoint without cURL extension.
  77  *
  78  * @param  string $url        Hub endpoint.
  79  * @param  string $postString String to POST.
  80  *
  81  * @return bool
  82  *
  83  * @throws Exception An error occurred.
  84  */
  85 function nocurl_http_post($url, $postString) {
  86     $params = array('http' => array(
  87         'method' => 'POST',
  88         'content' => $postString,
  89         'user_agent' => 'PubSubHubbub-Publisher-PHP/1.0',
  90     ));
  91
  92     $context = stream_context_create($params);
  93     $fp = @fopen($url, 'rb', false, $context);
  94     if (!$fp) {
  95         throw new Exception(sprintf(t('Could not post to %s'), $url));
  96     }
  97     $response = @stream_get_contents($fp);
  98     if ($response === false) {
  99         throw new Exception(sprintf(t('Bad response from the hub %s'), $url));
 100     }
 101     return $response;
 102 }
 103
 104 /**
 105  * This function is never called, but contains translation calls for GNU gettext extraction.
 106  */
 107 function pubsubhubbub_dummy_translation()
 108 {
 109     // meta
 110     t('Enable PubSubHubbub feed publishing.');
 111 }