First draft of PubSubHubbub

https://github.com/FreshRSS/FreshRSS/issues/312
Requires setting base_url in config.php.
Currently using the filesystem (no change to the database)

10 files changed, 252 insertions, 24 deletions

diff --git a/app/Controllers/feedController.php b/app/Controllers/feedController.php
index 0443b4159..9117da639 100755
--- a/app/Controllers/feedController.php
+++ b/app/Controllers/feedController.php
@@ -168,6 +168,7 @@ class FreshRSS_feed_Controller extends Minz_ActionController {
 			// Ok, feed has been added in database. Now we have to refresh entries.
 			$feed->_id($id);
 			$feed->faviconPrepare();
+			$feed->pubSubHubbubPrepare();
 
 			$is_read = FreshRSS_Context::$user_conf->mark_when['reception'] ? 1 : 0;
 
@@ -261,12 +262,13 @@ class FreshRSS_feed_Controller extends Minz_ActionController {
 	 * This action actualizes entries from one or several feeds.
 	 *
 	 * Parameters are:
-	 *   - id (default: false)
+	 *   - id (default: false): Feed ID
+	 *   - url (default: false): Feed URL
 	 *   - force (default: false)
-	 * If id is not specified, all the feeds are actualized. But if force is
+	 * If id and url are not specified, all the feeds are actualized. But if force is
 	 * false, process stops at 10 feeds to avoid time execution problem.
 	 */
-	public function actualizeAction() {
+	public function actualizeAction($simplePie = null) {
 		@set_time_limit(300);
 
 		$feedDAO = FreshRSS_Factory::createFeedDao();
@@ -274,14 +276,15 @@ class FreshRSS_feed_Controller extends Minz_ActionController {
 
 		Minz_Session::_param('actualize_feeds', false);
 		$id = Minz_Request::param('id');
+		$url = Minz_Request::param('url');
 		$force = Minz_Request::param('force');
 
 		// Create a list of feeds to actualize.
 		// If id is set and valid, corresponding feed is added to the list but
 		// alone in order to automatize further process.
 		$feeds = array();
-		if ($id) {
-			$feed = $feedDAO->searchById($id);
+		if ($id || $url) {
+			$feed = $id ? $feedDAO->searchById($id) : $feedDAO->searchByUrl($url);
 			if ($feed) {
 				$feeds[] = $feed;
 			}
@@ -302,8 +305,11 @@ class FreshRSS_feed_Controller extends Minz_ActionController {
 			}
 
 			try {
-				// Load entries
-				$feed->load(false);
+				if ($simplePie) {
+					$feed->loadEntries($simplePie);	//Used by PubSubHubbub
+				} else {
+					$feed->load(false);
+				}
 			} catch (FreshRSS_Feed_Exception $e) {
 				Minz_Log::notice($e->getMessage());
 				$feedDAO->updateLastUpdate($feed->id(), true);
@@ -404,7 +410,16 @@ class FreshRSS_feed_Controller extends Minz_ActionController {
 				$feedDAO->updateFeed($feed->id(), array('url' => $feed->url()));
 			}
 
-			$feed->faviconPrepare();
+			if ($simplePie === null) {
+				$feed->faviconPrepare();
+				if ($feed->url() === 'http://push-pub.appspot.com/feed') {
+					$secret = $feed->pubSubHubbubPrepare();
+					if ($secret != '') {
+						Minz_Log::debug('PubSubHubbub subscribe ' . $feed->url());
+						$feed->pubSubHubbubSubscribe(true, $secret);
+					}
+				}
+			}
 			$feed->unlock();
 			$updated_feeds++;
 			unset($feed);
@@ -427,20 +442,20 @@ class FreshRSS_feed_Controller extends Minz_ActionController {
 			Minz_Session::_param('notification', $notif);
 			// No layout in ajax request.
 			$this->view->_useLayout(false);
-			return;
-		}
-
-		// Redirect to the main page with correct notification.
-		if ($updated_feeds === 1) {
-			$feed = reset($feeds);
-			Minz_Request::good(_t('feedback.sub.feed.actualized', $feed->name()), array(
-				'params' => array('get' => 'f_' . $feed->id())
-			));
-		} elseif ($updated_feeds > 1) {
-			Minz_Request::good(_t('feedback.sub.feed.n_actualized', $updated_feeds), array());
 		} else {
-			Minz_Request::good(_t('feedback.sub.feed.no_refresh'), array());
+			// Redirect to the main page with correct notification.
+			if ($updated_feeds === 1) {
+				$feed = reset($feeds);
+				Minz_Request::good(_t('feedback.sub.feed.actualized', $feed->name()), array(
+					'params' => array('get' => 'f_' . $feed->id())
+				));
+			} elseif ($updated_feeds > 1) {
+				Minz_Request::good(_t('feedback.sub.feed.n_actualized', $updated_feeds), array());
+			} else {
+				Minz_Request::good(_t('feedback.sub.feed.no_refresh'), array());
+			}
 		}
+		return $updated_feeds;
 	}
 
 	/**
diff --git a/app/Models/Feed.php b/app/Models/Feed.php
index 85fb173ec..dcf083ea8 100644
--- a/app/Models/Feed.php
+++ b/app/Models/Feed.php
@@ -19,6 +19,8 @@ class FreshRSS_Feed extends Minz_Model {
 	private $ttl = -2;
 	private $hash = null;
 	private $lockPath = '';
+	private $hubUrl = '';
+	private $selfUrl = '';
 
 	public function __construct($url, $validate=true) {
 		if ($validate) {
@@ -226,6 +228,11 @@ class FreshRSS_Feed extends Minz_Model {
 					throw new FreshRSS_Feed_Exception(($errorMessage == '' ? 'Feed error' : $errorMessage) . ' [' . $url . ']');
 				}
 
+				$links = $feed->get_links('self');
+				$this->selfUrl = isset($links[0]) ? $links[0] : null;
+				$links = $feed->get_links('hub');
+				$this->hubUrl = isset($links[0]) ? $links[0] : null;
+
 				if ($loadDetails) {
 					// si on a utilisé l'auto-discover, notre url va avoir changé
 					$subscribe_url = $feed->subscribe_url(false);
@@ -259,7 +266,7 @@ class FreshRSS_Feed extends Minz_Model {
 		}
 	}
 
-	private function loadEntries($feed) {
+	public function loadEntries($feed) {
 		$entries = array();
 
 		foreach ($feed->get_items() as $item) {
@@ -333,4 +340,64 @@ class FreshRSS_Feed extends Minz_Model {
 	function unlock() {
 		@unlink($this->lockPath);
 	}
+
+	//<PubSubHubbub>
+
+	function pubSubHubbubPrepare() {
+		$secret = '';
+		if (FreshRSS_Context::$system_conf->base_url && $this->hubUrl && $this->selfUrl) {
+			$path = PSHB_PATH . '/feeds/' . base64url_encode($this->selfUrl);
+			if (!file_exists($path . '/hub.txt')) {
+				@mkdir($path, 0777, true);
+				file_put_contents($path . '/hub.txt', $this->hubUrl);
+				$secret = sha1(FreshRSS_Context::$system_conf->salt . uniqid(mt_rand(), true));
+				file_put_contents($path . '/secret.txt', $secret);
+				@mkdir(PSHB_PATH . '/secrets/');
+				file_put_contents(PSHB_PATH . '/secrets/' . $secret . '.txt', base64url_encode($this->selfUrl));
+				Minz_Log::notice('PubSubHubbub prepared for ' . $this->url);
+				file_put_contents(USERS_PATH . '/_/log_pshb.txt', date('c') . "\t" .
+					'PubSubHubbub prepared for ' . $this->url . "\n", FILE_APPEND);
+			}
+			$path .= '/' . base64url_encode($this->url);
+			$currentUser = Minz_Session::param('currentUser');
+			if (ctype_alnum($currentUser) && !file_exists($path . '/' . $currentUser . '.txt')) {
+				@mkdir($path, 0777, true);
+				touch($path . '/' . $currentUser . '.txt');
+			}
+		}
+		return $secret;
+	}
+
+	//Parameter true to subscribe, false to unsubscribe.
+	function pubSubHubbubSubscribe($state, $secret = '') {
+		if (FreshRSS_Context::$system_conf->base_url && $this->hubUrl && $this->selfUrl) {
+			$callbackUrl = checkUrl(FreshRSS_Context::$system_conf->base_url . 'api/pshb.php?s=' . $secret);
+			if ($callbackUrl == '') {
+				return false;
+			}
+
+			$ch = curl_init();
+			curl_setopt_array($ch, array(
+				CURLOPT_URL => $this->hubUrl,
+				CURLOPT_FOLLOWLOCATION => true,
+				CURLOPT_RETURNTRANSFER => true,
+				CURLOPT_USERAGENT => _t('gen.freshrss') . '/' . FRESHRSS_VERSION . ' (' . PHP_OS . '; ' . FRESHRSS_WEBSITE . ')',
+				CURLOPT_POSTFIELDS => 'hub.verify=sync'
+					. '&hub.mode=' . ($state ? 'subscribe' : 'unsubscribe')
+					. '&hub.topic=' . urlencode($this->selfUrl)
+					. '&hub.callback=' . urlencode($callbackUrl)
+				)
+			);
+			$response = curl_exec($ch);
+			$info = curl_getinfo($ch);
+
+			file_put_contents(USERS_PATH . '/_/log_pshb.txt', date('c') . "\t" .
+				'PubSubHubbub ' . ($state ? 'subscribe' : 'unsubscribe') . ' to ' . $this->selfUrl .
+				' with callback ' . $callbackUrl . ': ' . $info['http_code'] . ' ' . $response . "\n", FILE_APPEND);
+			return substr($info['http_code'], 0, 1) == '2';
+		}
+		return false;
+	}
+
+	//</PubSubHubbub>
 }
diff --git a/constants.php b/constants.php
index b20bf0710..5bb410e29 100644
--- a/constants.php
+++ b/constants.php
@@ -18,6 +18,7 @@ define('FRESHRSS_PATH', dirname(__FILE__));
 		define('UPDATE_FILENAME', DATA_PATH . '/update.php');
 		define('USERS_PATH', DATA_PATH . '/users');
 		define('CACHE_PATH', DATA_PATH . '/cache');
+		define('PSHB_PATH', DATA_PATH . '/PubSubHubbub');
 
 	define('LIB_PATH', FRESHRSS_PATH . '/lib');
 	define('APP_PATH', FRESHRSS_PATH . '/app');
diff --git a/data/PubSubHubbub/feeds/.gitignore b/data/PubSubHubbub/feeds/.gitignore
new file mode 100644
index 000000000..150f68c80
--- /dev/null
+++ b/data/PubSubHubbub/feeds/.gitignore
@@ -0,0 +1 @@
+*/*
diff --git a/data/PubSubHubbub/feeds/README.md b/data/PubSubHubbub/feeds/README.md
new file mode 100644
index 000000000..15fa8e521
--- /dev/null
+++ b/data/PubSubHubbub/feeds/README.md
@@ -0,0 +1,12 @@
+List of canonical URLS of the various feeds users have subscribed to.
+Several feeds can share the same canonical URL (rel="self").
+Several users can have subscribed to the same feed.
+
+* ./base64url(canonicalUrl)/
+	* ./secret.txt
+	* ./base64url(feedUrl1)/
+		* ./user1.txt
+		* ./user2.txt
+	* ./base64url(feedUrl2)/
+		* ./user3.txt
+		* ./user4.txt
diff --git a/data/PubSubHubbub/secrets/.gitignore b/data/PubSubHubbub/secrets/.gitignore
new file mode 100644
index 000000000..2211df63d
--- /dev/null
+++ b/data/PubSubHubbub/secrets/.gitignore
@@ -0,0 +1 @@
+*.txt
diff --git a/data/PubSubHubbub/secrets/README.md b/data/PubSubHubbub/secrets/README.md
new file mode 100644
index 000000000..ad8158839
--- /dev/null
+++ b/data/PubSubHubbub/secrets/README.md
@@ -0,0 +1,4 @@
+List of secrets given to PubSubHubbub hubs
+
+* ./sha1(random + salt).txt
+	* base64url(canonicalUrl)
diff --git a/data/config.default.php b/data/config.default.php
index 8be203d36..80d331df7 100644
--- a/data/config.default.php
+++ b/data/config.default.php
@@ -11,9 +11,11 @@ return array(
 	# Used to make crypto more unique. Generated during install.
 	'salt' => '',
 
-	# Leave empty for most cases.
-	# Ability to override the address of the FreshRSS instance,
-	# used when building absolute URLs.
+	# Specify address of the FreshRSS instance,
+	# used when building absolute URLs, e.g. for PubSubHubbub.
+	# Examples:
+	# https://example.net/FreshRSS/p/
+	# https://freshrss.example.net/
 	'base_url' => '',
 
 	# Natural language of the user interface, e.g. `en`, `fr`.
diff --git a/lib/lib_rss.php b/lib/lib_rss.php
index 6342011c8..191a58f35 100644
--- a/lib/lib_rss.php
+++ b/lib/lib_rss.php
@@ -446,3 +446,12 @@ function array_push_unique(&$array, $value) {
 function array_remove(&$array, $value) {
 	$array = array_diff($array, array($value));
 }
+
+//RFC 4648
+function base64url_encode($data) {
+	return strtr(rtrim(base64_encode($data), '='), '+/', '-_');
+}
+//RFC 4648
+function base64url_decode($data) {
+	return base64_decode(strtr($data, '-_', '+/'));
+}
diff --git a/p/api/pshb.php b/p/api/pshb.php
new file mode 100644
index 000000000..bcb8341b1
--- /dev/null
+++ b/p/api/pshb.php
@@ -0,0 +1,116 @@
+<?php
+require('../../constants.php');
+require(LIB_PATH . '/lib_rss.php');	//Includes class autoloader
+
+define('MAX_PAYLOAD', 3145728);
+
+header('Content-Type: text/plain; charset=UTF-8');
+
+function logMe($text) {
+	file_put_contents(USERS_PATH . '/_/log_pshb.txt', date('c') . "\t" . $text . "\n", FILE_APPEND);
+}
+
+$ORIGINAL_INPUT = file_get_contents('php://input', false, null, -1, MAX_PAYLOAD);
+
+logMe(print_r(array('_GET' => $_GET, '_POST' => $_POST, 'INPUT' => $ORIGINAL_INPUT), true));
+
+$secret = isset($_GET['s']) ? substr($_GET['s'], 0, 128) : '';
+if (!ctype_xdigit($secret)) {
+	header('HTTP/1.1 422 Unprocessable Entity');
+	die('Invalid feed secret format!');
+}
+chdir(PSHB_PATH);
+$canonical64 = @file_get_contents('secrets/' . $secret . '.txt');
+if ($canonical64 === false) {
+	header('HTTP/1.1 404 Not Found');
+	logMe('Feed secret not found!: ' . $secret);
+	die('Feed secret not found!');
+}
+$canonical64 = trim($canonical64);
+if (!preg_match('/^[A-Za-z0-9_-]+$/D', $canonical64)) {
+	header('HTTP/1.1 500 Internal Server Error');
+	logMe('Invalid secret reference!: ' . $canonical64);
+	die('Invalid secret reference!');
+}
+$secret2 = @file_get_contents('feeds/' . $canonical64 . '/secret.txt');
+if ($secret2 === false) {
+	header('HTTP/1.1 404 Not Found');
+	//@unlink('secrets/' . $secret . '.txt');
+	logMe('Feed reverse secret not found!: ' . $canonical64);
+	die('Feed reverse secret not found!');
+}
+if ($secret !== $secret2) {
+	header('HTTP/1.1 500 Internal Server Error');
+	logMe('Invalid secret cross-check!: ' . $secret);
+	die('Invalid secret cross-check!');
+}
+chdir('feeds/' . $canonical64);
+$users = glob('*/*.txt', GLOB_NOSORT);
+if (empty($users)) {
+	header('HTTP/1.1 410 Gone');
+	logMe('Nobody is subscribed to this feed anymore!: ' . $canonical64);
+	die('Nobody is subscribed to this feed anymore!');
+}
+
+if (!empty($_REQUEST['hub_mode']) && $_REQUEST['hub_mode'] === 'subscribe') {
+	//TODO: hub_lease_seconds
+	exit(isset($_REQUEST['hub_challenge']) ? $_REQUEST['hub_challenge'] : '');
+}
+
+Minz_Configuration::register('system', DATA_PATH . '/config.php', DATA_PATH . '/config.default.php');
+$system_conf = Minz_Configuration::get('system');
+$system_conf->auth_type = 'none';	// avoid necessity to be logged in (not saved!)
+Minz_Translate::init('en');
+Minz_Request::_param('ajax', true);
+$feedController = new FreshRSS_feed_Controller();
+
+$simplePie = customSimplePie();
+$simplePie->set_raw_data($ORIGINAL_INPUT);
+$simplePie->init();
+unset($ORIGINAL_INPUT);
+
+$links = $simplePie->get_links('self');
+$self = isset($links[0]) ? $links[0] : null;
+
+if ($self !== base64url_decode($canonical64)) {
+	header('HTTP/1.1 422 Unprocessable Entity');
+	logMe('Self URL does not match registered canonical URL!: ' . $self);
+	die('Self URL does not match registered canonical URL!');
+}
+Minz_Request::_param('url', $self);
+
+$nb = 0;
+foreach ($users as $userLine) {
+	$userLine = strtr($userLine, '\\', '/');
+	$userInfos = explode('/', $userLine);
+	$feedUrl = isset($userInfos[0]) ? base64url_decode($userInfos[0]) : '';
+	$username = isset($userInfos[1]) ? basename($userInfos[1], '.txt') : '';
+	if (!file_exists(USERS_PATH . '/' . $username . '/config.php')) {
+		break;
+	}
+
+	try {
+		Minz_Session::_param('currentUser', $username);
+		Minz_Configuration::register('user',
+		                             join_path(USERS_PATH, $username, 'config.php'),
+		                             join_path(USERS_PATH, '_', 'config.default.php'));
+		FreshRSS_Context::init();
+		if ($feedController->actualizeAction($simplePie) > 0) {
+			$nb++;
+		}
+	} catch (Exception $e) {
+		logMe($e->getMessage());
+	}
+}
+
+$simplePie->__destruct();
+unset($simplePie);
+
+if ($nb === 0) {
+	header('HTTP/1.1 410 Gone');
+	logMe('Nobody is subscribed to this feed anymore after all!: ' . $self);
+	die('Nobody is subscribed to this feed anymore after all!');
+}
+
+logMe($self . ' done: ' . $nb);
+exit('Done: ' . $nb . "\n");