pubsubhubbub.php

<?php
/**
 * Plugin Name: PubSubHubbub
 * Plugin URI: https://github.com/pubsubhubbub/
 * Description: A better way to tell the world when your blog is updated.
 * Version: 1.7.2
 * Author: Josh Fraser, Matthias Pfefferle
 * Author Email: joshfraz@gmail.com
 * Author URI: https://wordpress.org/plugins/pubsubhubbub/
 * Domain Path: /languages
 */

include( 'publisher.php' );

/**
 * the ability for other plugins to hook into the PuSH code
 *
 * @param array $feed_urls a list of feed urls you want to publish
 */
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
 *
 * @param int $post_id the post-id
 * @return int the post-id
 */
function pshb_publish_post( $post_id ) {
	// get default feeds
	$feed_urls = pshb_get_feed_urls();

	// publish them
	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
 *
 * @param int $comment_id the comment-id
 * @return int the comment-id
 */
function pshb_publish_comment( $comment_id ) {
	// get default comment-feeds
	$feed_urls	 = pshb_get_comment_feed_urls();

	// publish them
	pshb_publish_to_hub( $feed_urls );

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

/**
 * add hub-<link> to the 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 hub-<link> to the rss/rdf feed
 */
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' );

/**
 * add atom namespace to rdf-feed
 */
function pshb_add_rdf_ns_link() {
	echo ' xmlns:atom="http://www.w3.org/2005/Atom" ' . PHP_EOL;
}
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"
 *
 *	@uses apply_filters() Calls 'pshb_hub_urls' filter
 */
function pshb_get_pubsub_endpoints() {
	$endpoints = get_option( 'pubsub_endpoints' );
	$hub_urls = explode( PHP_EOL, $endpoints );

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

/**
 * helper function to get feed urls
 *
 * @uses apply_filters() Calls 'pshb_feed_urls' filter
 */
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
 *
 * @uses apply_filters() Calls 'pshb_comment_feed_urls' filter
 */
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><?php _e( 'Define custom hubs', 'pubsubhubbub' ); ?></h2>

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

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

	<table class="form-table">
		<tr valign="top">
			<th scope="row"><?php _e( 'Hubs (one per line)', 'pubsubhubbub' ); ?></th>
			<td><textarea name="pubsub_endpoints" rows="10" cols="50" class="large-text"><?php echo $pubsub_endpoints; ?></textarea></td>
		</tr>
	</table>

	<?php submit_button(); ?>

	</form>

	<p><strong><?php _e( 'Thanks for using PubSubHubbub!', 'pubsubhubbub' ); ?></strong></p>

	<p><?php _e( 'Visit these links to learn more about PubSubHubbub and the author of this plugin:', 'pubsubhubbub' ); ?></p>
	<ul>
		<li><?php printf( __( 'Subscribe to %s or %s (german)' ), '<a href="http://www.onlineaspect.com">Online Aspect</a>', '<a href="http://notizblog.org/">notizBlog</a>' ) ?></li>
		<li><?php printf( __( 'Follow %s or %s on twitter' ), '<a href="http://twitter.com/joshfraser">Josh Fraser</a>', '<a href="http://twitter.com/pfefferle">Matthias Pfefferle</a>' ) ?></li>
		<li><a href="http://code.google.com/p/pubsubhubbub/"><?php _e( 'Learn more about the PubSubHubbub protocol', 'pubsubhubbub' ); ?></a></li>
	</ul>
</div>

<?php }

/**
 * add a settings link next to deactive / edit
 */
function pshb_add_settings_link( $links, $file ) {
	if ( 'pubsubhubbub/pubsubhubbub.php' == $file && 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
 *
 * @param array $vars a list of query-vars
 * @return array the list with the added PuSH params
 */
function pshb_query_var($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 current v0.4 draft
 *
 * @link https://github.com/pubsubhubbub/PubSubHubbub/issues/2
 */
function pshb_template_redirect() {
	// get all feeds
	$feed_urls = pshb_get_feed_urls();
	$comment_feed_urls = pshb_get_comment_feed_urls();

	// get current url
	$urls = array_unique( array_merge( $feed_urls, $comment_feed_urls ) );
	$current_url = ( is_ssl() ? 'https://' : 'http://' ) . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];

	// check if current url is one of the feed urls
	if ( in_array( $current_url, $urls ) ) {
		$hub_urls = pshb_get_pubsub_endpoints();
		// add all "hub" headers
		foreach ( $hub_urls as $hub_url ) {
			header( 'Link: <'.$hub_url.'>; rel="hub"', false );
		}
		// add the "self" header
		header( 'Link: <'.$current_url.'>; rel="self"', false );
	}
}
add_action( 'template_redirect', 'pshb_template_redirect' );

/**
 * keep WPMU happy
 */
function pshb_register_settings() {
	register_setting( 'pubsubhubbub_options','pubsub_endpoints' );
}
add_action( 'admin_init', 'pshb_register_settings' );

// Load the plugin textdomain.
function pshb_load_textdomain() {
	load_plugin_textdomain( 'pubsubhubbub', false, basename( dirname( plugin_dir_path( __FILE__ ) ) ) . '/languages' );
}
add_action( 'init', 'pshb_load_textdomain' );

/**
 * beeing backwards compatible
 * based on a fix by Stephen Paul Weber (http://singpolyma.net)
 *
 * @deprecated
 */
function publish_to_hub( $deprecated = null, $feed_urls ) {
	pshb_publish_to_hub( $feed_urls );
}