pubsubhubbub.php

<?php
/*
Plugin Name: PubSubHubbub
Plugin URI: http://code.google.com/p/pubsubhubbub/
Description: A better way to tell the world when your blog is updated.
Version: 1.6.5
Author: Josh Fraser, Matthias Pfefferle
Author Email: joshfraz@gmail.com
Author URI: http://wordpress.org/extend/plugins/pubsubhubbub/
*/

include("publisher.php");

// the ability for other plugins to hook into the PuSH code based on a
// fix by Stephen Paul Weber (http://singpolyma.net)
function pshb_publish_to_hub($feed_urls)  {
  // remove dups (ie. they all point to feedburner)
  $feed_urls = array_unique($feed_urls);
  // get the list of hubs
  $hub_urls = pshb_get_pubsub_endpoints();
  // loop through each hub
  foreach ($hub_urls as $hub_url) {
    $p = new PshbPublisher($hub_url);
    // publish the update to each hub
    if (!$p->publish_update($feed_urls)) {
      // TODO: add better error handling here
    }
  }
}

// function that is called whenever a new post is published
function pshb_publish_post($post_id) {
  // customize default feeds
  $feed_urls   = pshb_get_feed_urls();

  pshb_publish_to_hub($feed_urls);

  return $post_id;
}
add_action('publish_post', 'pshb_publish_post');

// function that is called whenever a new comment is published
function pshb_publish_comment($comment_id) {
  // customize default feeds
  $feed_urls   = pshb_get_comment_feed_urls();

  pshb_publish_to_hub($feed_urls);

  return $comment_id;
}
add_action('comment_post', 'pshb_publish_comment');

// to our atom feed
function pshb_add_atom_link_tag() {
  $hub_urls = pshb_get_pubsub_endpoints();
  foreach ($hub_urls as $hub_url) {
    echo '<link rel="hub" href="'.$hub_url.'" />';
  }
}
add_action('atom_head', 'pshb_add_atom_link_tag');
add_action('comments_atom_head', 'pshb_add_atom_link_tag');
//add_action('wp_head', 'pshb_add_atom_link_tag');

function pshb_add_rss_link_tag() {
  $hub_urls = pshb_get_pubsub_endpoints();
  foreach ($hub_urls as $hub_url) {
    echo '<atom:link rel="hub" href="'.$hub_url.'"/>';
  }
}
add_action('rss_head', 'pshb_add_rss_link_tag');
add_action('rdf_header', 'pshb_add_rss_link_tag');
add_action('rss2_head', 'pshb_add_rss_link_tag');
add_action('commentsrss2_head', 'pshb_add_rss_link_tag');

function pshb_add_rdf_ns_link() {
  echo 'xmlns:atom="http://www.w3.org/2005/Atom"'."\n";
}
add_action('rdf_ns', 'pshb_add_rdf_ns_link');

// hack to add the atom definition to the RSS feed
// start capturing the feed output.  this is run at priority 9 (before output)
function pshb_start_rss_link_tag() {
  ob_start();
}
add_action('do_feed_rss', 'pshb_start_rss_link_tag', 9); // run before output

// this is run at priority 11 (after output)
// add in the xmlns atom definition link
function pshb_end_rss_link_tag() {
  $feed = ob_get_clean();
  $pattern = '/<rss version="(.+)">/i';
  $replacement = '<rss version="$1" xmlns:atom="http://www.w3.org/2005/Atom">';
  // change <rss version="X.XX"> to <rss version="X.XX" xmlns:atom="http://www.w3.org/2005/Atom">
  echo preg_replace($pattern, $replacement, $feed);
}
add_action('do_feed_rss', 'pshb_end_rss_link_tag', 11); // run after output

// add a link to our settings page in the WP menu
function pshb_add_plugin_menu() {
  add_options_page('PubSubHubbub Settings', 'PubSubHubbub', 'administrator', 'pubsubhubbub', 'pshb_add_settings_page');
}
add_action('admin_menu', 'pshb_add_plugin_menu');

// get the endpoints from the wordpress options table
// valid parameters are "publish" or "subscribe"
function pshb_get_pubsub_endpoints() {
  $endpoints = get_option('pubsub_endpoints');
  $hub_urls = explode("\n",$endpoints);

  // if no values have been set, revert to the defaults (pubsubhubbub on app engine & superfeedr)
  if (!$endpoints) {
    $hub_urls[] = "http://pubsubhubbub.appspot.com";
    $hub_urls[] = "http://pubsubhubbub.superfeedr.com";
  }

  // clean out any blank values
  foreach ($hub_urls as $key => $value) {
    if (is_null($value) || $value=="") {
      unset($hub_urls[$key]);
    } else {
      $hub_urls[$key] = trim($hub_urls[$key]);
    }
  }

  return $hub_urls;
}

// helper function to get feed urls
function pshb_get_feed_urls() {
  // we want to notify the hub for every feed
  $feed_urls = array();
  $feed_urls[] = get_bloginfo('atom_url');
  $feed_urls[] = get_bloginfo('rss_url');
  $feed_urls[] = get_bloginfo('rdf_url');
  $feed_urls[] = get_bloginfo('rss2_url');

  return apply_filters('pshb_feed_urls', $feed_urls);
}

// helper function to get comment-feed urls
function pshb_get_comment_feed_urls() {
  // we want to notify the hub for every feed
  $feed_urls = array();
  $feed_urls[] = get_bloginfo('comments_atom_url');
  $feed_urls[] = get_bloginfo('comments_rss2_url');

  return apply_filters('pshb_comment_feed_urls', $feed_urls);
}

// write the content for our settings page that allows you to define your endpoints
function pshb_add_settings_page() { ?>
  <div class="wrap">
  <h2>Define custom hubs</h2>

  <form method="post" action="options.php">
  <?php //wp_nonce_field('update-options'); ?>
  <!-- starting -->
  <?php settings_fields('my_settings_group'); ?>
  <?php do_settings_sections('my_settings_section'); ?>
  <!-- ending -->

  <?php
  // load the existing pubsub endpoint list from the wordpress options table
  $pubsub_endpoints = trim(implode("\n",pshb_get_pubsub_endpoints()),"\n");
  ?>

  <table class="form-table">

  <tr valign="top">
  <th scope="row">Hubs (one per line)</th>
  <td><textarea name="pubsub_endpoints" style='width:600px;height:100px'><?php echo $pubsub_endpoints; ?></textarea></td>
  </tr>

  </table>

  <input type="hidden" name="action" value="update" />
  <input type="hidden" name="page_options" value="pubsub_endpoints" />

  <p class="submit">
  <input type="submit" class="button-primary" value="<?php _e('Save Changes') ?>" />
  </p>

  </form>

  <br /><br />
  <div style='background-color:#FFFEEB;border:1px solid #CCCCCC;padding:12px'>
    <strong>Thanks for using PubSubHubbub!</strong><br />
    Visit these links to learn more about PubSubHubbub and the author of this plugin:<br />
    <ul>
      <li><a href='http://www.onlineaspect.com'>Subscribe to Online Aspect</a></li>
      <li><a href='http://www.twitter.com/joshfraser'>Follow Josh Fraser on twitter</a></li>
      <li><a href='http://code.google.com/p/pubsubhubbub/'>Learn more about the PubSubHubbub protocol</a></li>
    </ul>
  </div>
</div>

<?php }

// add a settings link next to deactive / edit
function pshb_add_settings_link( $links, $file ) {
  if( $file == 'pubsubhubbub/pubsubhubbub.php' && function_exists( "admin_url" ) ) {
    $settings_link = '<a href="' . admin_url( 'options-general.php?page=pubsubhubbub' ) . '">' . __('Settings') . '</a>';
    array_unshift( $links, $settings_link ); // before other links
  }
  return $links;
}
add_filter('plugin_action_links', 'pshb_add_settings_link', 10, 2);

// adds some query vars
function pshb_query_var($vars) {
  $vars[] = 'hub_mode';
  $vars[] = 'hub_challenge';
  $vars[] = 'hub_topic';
  $vars[] = 'hub_url';
  $vars[] = 'pubsubhubbub';
  return $vars;
}
add_filter('query_vars', 'pshb_query_var');

// adds link headers as defined in the curren v0.4 draft
// https://github.com/pubsubhubbub/PubSubHubbub/issues/2
function pshb_template_redirect() {
  global $wp;

  $feed_urls = pshb_get_feed_urls();
  $comment_feed_urls = pshb_get_comment_feed_urls();
  
  $urls = array_unique(array_merge($feed_urls, $comment_feed_urls));
  $current_url = ( is_ssl() ? 'https://' : 'http://' ) . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
  
  if (in_array($current_url, $urls)) {
    $hub_urls = pshb_get_pubsub_endpoints();
    foreach ($hub_urls as $hub_url) {
      header('Link: <'.$hub_url.'>; rel="hub"', false);
    }
    header('Link: <'.$current_url.'>; rel="self"', false);
  }
}
add_action('template_redirect', 'pshb_template_redirect');

// keep WPMU happy
function pshb_register_my_settings() {
  register_setting('my_settings_group','pubsub_endpoints');
}
add_action('admin_init', 'pshb_register_my_settings');

/**
 * beeing backwards compatible
 * @deprecated
 */
function publish_to_hub($deprecated = null, $feed_urls)  {
  pshb_publish_to_hub($feed_urls);
}