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 use Shaarli\Feed\FeedBuilder;
  15
  16 /**
  17  * Plugin init function - set the hub to the default appspot one.
  18  *
  19  * @param ConfigManager $conf instance.
  20  */
  21 function pubsubhubbub_init($conf)
  22 {
  23     $hub = $conf->get('plugins.PUBSUBHUB_URL');
  24     if (empty($hub)) {
  25         // Default hub.
  26         $conf->set('plugins.PUBSUBHUB_URL', 'https://pubsubhubbub.appspot.com/');
  27     }
  28 }
  29
  30
  31 /**
  32  * Render feed hook.
  33  * Adds the hub URL in ATOM and RSS feed.
  34  *
  35  * @param array         $data Template data.
  36  * @param ConfigManager $conf instance.
  37  *
  38  * @return array updated template data.
  39  */
  40 function hook_pubsubhubbub_render_feed($data, $conf)
  41 {
  42     $feedType = $data['_PAGE_'] == Router::$PAGE_FEED_RSS ? FeedBuilder::$FEED_RSS : FeedBuilder::$FEED_ATOM;
  43     $template = file_get_contents(PluginManager::$PLUGINS_PATH . '/pubsubhubbub/hub.'. $feedType .'.xml');
  44     $data['feed_plugins_header'][] = sprintf($template, $conf->get('plugins.PUBSUBHUB_URL'));
  45
  46     return $data;
  47 }
  48
  49 /**
  50  * Save link hook.
  51  * Publish to the hub when a link is saved.
  52  *
  53  * @param array         $data Template data.
  54  * @param ConfigManager $conf instance.
  55  *
  56  * @return array unaltered data.
  57  */
  58 function hook_pubsubhubbub_save_link($data, $conf)
  59 {
  60     $feeds = array(
  61         index_url($_SERVER) .'?do=atom',
  62         index_url($_SERVER) .'?do=rss',
  63     );
  64
  65     $httpPost = function_exists('curl_version') ? false : 'nocurl_http_post';
  66     try {
  67         $p = new Publisher($conf->get('plugins.PUBSUBHUB_URL'));
  68         $p->publish_update($feeds, $httpPost);
  69     } catch (Exception $e) {
  70         error_log(sprintf(t('Could not publish to PubSubHubbub: %s'), $e->getMessage()));
  71     }
  72
  73     return $data;
  74 }
  75
  76 /**
  77  * Http function used to post to the hub endpoint without cURL extension.
  78  *
  79  * @param  string $url        Hub endpoint.
  80  * @param  string $postString String to POST.
  81  *
  82  * @return bool
  83  *
  84  * @throws Exception An error occurred.
  85  */
  86 function nocurl_http_post($url, $postString)
  87 {
  88     $params = array('http' => array(
  89         'method' => 'POST',
  90         'content' => $postString,
  91         'user_agent' => 'PubSubHubbub-Publisher-PHP/1.0',
  92     ));
  93
  94     $context = stream_context_create($params);
  95     $fp = @fopen($url, 'rb', false, $context);
  96     if (!$fp) {
  97         throw new Exception(sprintf(t('Could not post to %s'), $url));
  98     }
  99     $response = @stream_get_contents($fp);
 100     if ($response === false) {
 101         throw new Exception(sprintf(t('Bad response from the hub %s'), $url));
 102     }
 103     return $response;
 104 }
 105
 106 /**
 107  * This function is never called, but contains translation calls for GNU gettext extraction.
 108  */
 109 function pubsubhubbub_dummy_translation()
 110 {
 111     // meta
 112     t('Enable PubSubHubbub feed publishing.');
 113 }