*/
require_once 'Stomp.php';
+require_once 'Stomp/Exception.php';
-class LiberalStomp extends Stomp
+class StompQueueManager extends QueueManager
{
- function getSocket()
- {
- return $this->_socket;
- }
-}
+ protected $servers;
+ protected $username;
+ protected $password;
+ protected $base;
+ protected $control;
-class StompQueueManager
-{
- var $server = null;
- var $username = null;
- var $password = null;
- var $base = null;
- var $con = null;
+ protected $useTransactions = true;
+
+ protected $sites = array();
+ protected $subscriptions = array();
+
+ protected $cons = array(); // all open connections
+ protected $disconnect = array();
+ protected $transaction = array();
+ protected $transactionCount = array();
+ protected $defaultIdx = 0;
function __construct()
{
- $this->server = common_config('queue', 'stomp_server');
+ parent::__construct();
+ $server = common_config('queue', 'stomp_server');
+ if (is_array($server)) {
+ $this->servers = $server;
+ } else {
+ $this->servers = array($server);
+ }
$this->username = common_config('queue', 'stomp_username');
$this->password = common_config('queue', 'stomp_password');
$this->base = common_config('queue', 'queue_basename');
+ $this->control = common_config('queue', 'control_channel');
+ $this->breakout = common_config('queue', 'breakout');
}
- function _connect()
+ /**
+ * Tell the i/o master we only need a single instance to cover
+ * all sites running in this process.
+ */
+ public static function multiSite()
{
- if (empty($this->con)) {
- $this->_log(LOG_INFO, "Connecting to '$this->server' as '$this->username'...");
- $this->con = new LiberalStomp($this->server);
+ return IoManager::INSTANCE_PER_PROCESS;
+ }
- if ($this->con->connect($this->username, $this->password)) {
- $this->_log(LOG_INFO, "Connected.");
- } else {
- $this->_log(LOG_ERR, 'Failed to connect to queue server');
- throw new ServerException('Failed to connect to queue server');
- }
+ /**
+ * Optional; ping any running queue handler daemons with a notification
+ * such as announcing a new site to handle or requesting clean shutdown.
+ * This avoids having to restart all the daemons manually to update configs
+ * and such.
+ *
+ * Currently only relevant for multi-site queue managers such as Stomp.
+ *
+ * @param string $event event key
+ * @param string $param optional parameter to append to key
+ * @return boolean success
+ */
+ public function sendControlSignal($event, $param='')
+ {
+ $message = $event;
+ if ($param != '') {
+ $message .= ':' . $param;
+ }
+ $this->_connect();
+ $con = $this->cons[$this->defaultIdx];
+ $result = $con->send($this->control,
+ $message,
+ array ('created' => common_sql_now()));
+ if ($result) {
+ $this->_log(LOG_INFO, "Sent control ping to queue daemons: $message");
+ return true;
+ } else {
+ $this->_log(LOG_ERR, "Failed sending control ping to queue daemons: $message");
+ return false;
}
}
- function enqueue($object, $queue)
+ /**
+ * Saves an object into the queue item table.
+ *
+ * @param mixed $object
+ * @param string $queue
+ *
+ * @return boolean true on success
+ * @throws StompException on connection or send error
+ */
+ public function enqueue($object, $queue)
{
- $notice = $object;
-
$this->_connect();
+ return $this->_doEnqueue($object, $queue, $this->defaultIdx);
+ }
+
+ /**
+ * Saves a notice object reference into the queue item table
+ * on the given connection.
+ *
+ * @return boolean true on success
+ * @throws StompException on connection or send error
+ */
+ protected function _doEnqueue($object, $queue, $idx)
+ {
+ $rep = $this->logrep($object);
+ $envelope = array('site' => common_config('site', 'nickname'),
+ 'handler' => $queue,
+ 'payload' => $this->encode($object));
+ $msg = serialize($envelope);
- // XXX: serialize and send entire notice
+ $props = array('created' => common_sql_now());
+ if ($this->isPersistent($queue)) {
+ $props['persistent'] = 'true';
+ }
- $result = $this->con->send($this->_queueName($queue),
- $notice->id, // BODY of the message
- array ('created' => $notice->created));
+ $con = $this->cons[$idx];
+ $host = $con->getServer();
+ $target = $this->queueName($queue);
+ $result = $con->send($target, $msg, $props);
if (!$result) {
- common_log(LOG_ERR, 'Error sending to '.$queue.' queue');
+ $this->_log(LOG_ERR, "Error sending $rep to $queue queue on $host $target");
return false;
}
- common_log(LOG_DEBUG, 'complete remote queueing notice ID = '
- . $notice->id . ' for ' . $queue);
+ $this->_log(LOG_DEBUG, "complete remote queueing $rep for $queue on $host $target");
+ $this->stats('enqueued', $queue);
+ return true;
}
- function service($queue, $handler)
+ /**
+ * Determine whether messages to this queue should be marked as persistent.
+ * Actual persistent storage depends on the queue server's configuration.
+ * @param string $queue
+ * @return bool
+ */
+ protected function isPersistent($queue)
{
- $result = null;
-
- $this->_connect();
+ $mode = common_config('queue', 'stomp_persistent');
+ if (is_array($mode)) {
+ return in_array($queue, $mode);
+ } else {
+ return (bool)$mode;
+ }
+ }
- $this->con->setReadTimeout($handler->timeout());
+ /**
+ * Send any sockets we're listening on to the IO manager
+ * to wait for input.
+ *
+ * @return array of resources
+ */
+ public function getSockets()
+ {
+ $sockets = array();
+ foreach ($this->cons as $con) {
+ if ($con) {
+ $sockets[] = $con->getSocket();
+ }
+ }
+ return $sockets;
+ }
- $this->con->subscribe($this->_queueName($queue));
+ /**
+ * Get the Stomp connection object associated with the given socket.
+ * @param resource $socket
+ * @return int index into connections list
+ * @throws Exception
+ */
+ protected function connectionFromSocket($socket)
+ {
+ foreach ($this->cons as $i => $con) {
+ if ($con && $con->getSocket() === $socket) {
+ return $i;
+ }
+ }
+ throw new Exception(__CLASS__ . " asked to read from unrecognized socket");
+ }
- while (true) {
+ /**
+ * We've got input to handle on our socket!
+ * Read any waiting Stomp frame(s) and process them.
+ *
+ * @param resource $socket
+ * @return boolean ok on success
+ */
+ public function handleInput($socket)
+ {
+ $idx = $this->connectionFromSocket($socket);
+ $con = $this->cons[$idx];
+ $host = $con->getServer();
+ $this->defaultIdx = $idx;
- // Wait for something on one of our sockets
+ $ok = true;
+ try {
+ $frames = $con->readFrames();
+ } catch (StompException $e) {
+ $this->_log(LOG_ERR, "Lost connection to $host: " . $e->getMessage());
+ fclose($socket); // ???
+ $this->cons[$idx] = null;
+ $this->transaction[$idx] = null;
+ $this->disconnect[$idx] = time();
+ return false;
+ }
+ foreach ($frames as $frame) {
+ $dest = $frame->headers['destination'];
+ if ($dest == $this->control) {
+ if (!$this->handleControlSignal($frame)) {
+ // We got a control event that requests a shutdown;
+ // close out and stop handling anything else!
+ break;
+ }
+ } else {
+ $ok = $this->handleItem($frame) && $ok;
+ }
+ $this->ack($idx, $frame);
+ $this->commit($idx);
+ $this->begin($idx);
+ }
+ return $ok;
+ }
- $stompsock = $this->con->getSocket();
+ /**
+ * Attempt to reconnect in background if we lost a connection.
+ */
+ function idle()
+ {
+ $now = time();
+ foreach ($this->cons as $idx => $con) {
+ if (empty($con)) {
+ $age = $now - $this->disconnect[$idx];
+ if ($age >= 60) {
+ $this->_reconnect($idx);
+ }
+ }
+ }
+ return true;
+ }
- $handsocks = $handler->getSockets();
+ /**
+ * Initialize our connection and subscribe to all the queues
+ * we're going to need to handle... If multiple queue servers
+ * are configured for failover, we'll listen to all of them.
+ *
+ * Side effects: in multi-site mode, may reset site configuration.
+ *
+ * @param IoMaster $master process/event controller
+ * @return bool return false on failure
+ */
+ public function start($master)
+ {
+ parent::start($master);
+ $this->_connectAll();
- $socks = array_merge(array($stompsock), $handsocks);
+ foreach ($this->cons as $i => $con) {
+ if ($con) {
+ $this->doSubscribe($con);
+ $this->begin($i);
+ }
+ }
+ return true;
+ }
- $read = $socks;
- $write = array();
- $except = array();
+ /**
+ * Close out any active connections.
+ *
+ * @return bool return false on failure
+ */
+ public function finish()
+ {
+ // If there are any outstanding delivered messages we haven't processed,
+ // free them for another thread to take.
+ foreach ($this->cons as $i => $con) {
+ if ($con) {
+ $this->rollback($i);
+ $con->disconnect();
+ $this->cons[$i] = null;
+ }
+ }
+ return true;
+ }
- $ready = stream_select($read, $write, $except, $handler->timeout(), 0);
+ /**
+ * Lazy open a single connection to Stomp queue server.
+ * If multiple servers are configured, we let the Stomp client library
+ * worry about finding a working connection among them.
+ */
+ protected function _connect()
+ {
+ if (empty($this->cons)) {
+ $list = $this->servers;
+ if (count($list) > 1) {
+ shuffle($list); // Randomize to spread load
+ $url = 'failover://(' . implode(',', $list) . ')';
+ } else {
+ $url = $list[0];
+ }
+ $con = $this->_doConnect($url);
+ $this->cons = array($con);
+ $this->transactionCount = array(0);
+ $this->transaction = array(null);
+ $this->disconnect = array(null);
+ }
+ }
- if ($ready === false) {
- $this->_log(LOG_ERR, "Error selecting on sockets");
- } else if ($ready > 0) {
- if (in_array($stompsock, $read)) {
- $this->_handleNotice($queue, $handler);
+ /**
+ * Lazy open connections to all Stomp servers, if in manual failover
+ * mode. This means the queue servers don't speak to each other, so
+ * we have to listen to all of them to make sure we get all events.
+ */
+ protected function _connectAll()
+ {
+ if (!common_config('queue', 'stomp_manual_failover')) {
+ return $this->_connect();
+ }
+ if (empty($this->cons)) {
+ $this->cons = array();
+ $this->transactionCount = array();
+ $this->transaction = array();
+ foreach ($this->servers as $idx => $server) {
+ try {
+ $this->cons[] = $this->_doConnect($server);
+ $this->disconnect[] = null;
+ } catch (Exception $e) {
+ // s'okay, we'll live
+ $this->cons[] = null;
+ $this->disconnect[] = time();
}
- $handler->idle(QUEUE_HANDLER_HIT_IDLE);
+ $this->transactionCount[] = 0;
+ $this->transaction[] = null;
+ }
+ if (empty($this->cons)) {
+ throw new ServerException("No queue servers reachable...");
+ return false;
}
}
+ }
+
+ /**
+ * Attempt to manually reconnect to the Stomp server for the given
+ * slot. If successful, set up our subscriptions on it.
+ */
+ protected function _reconnect($idx)
+ {
+ try {
+ $con = $this->_doConnect($this->servers[$idx]);
+ } catch (Exception $e) {
+ $this->_log(LOG_ERR, $e->getMessage());
+ $con = null;
+ }
+ if ($con) {
+ $this->cons[$idx] = $con;
+ $this->disconnect[$idx] = null;
- $this->con->unsubscribe($this->_queueName($queue));
+ $this->doSubscribe($con);
+ $this->begin($idx);
+ } else {
+ // Try again later...
+ $this->disconnect[$idx] = time();
+ }
}
- function _handleNotice($queue, $handler)
+ protected function _doConnect($server)
{
- $frame = $this->con->readFrame();
+ $this->_log(LOG_INFO, "Connecting to '$server' as '$this->username'...");
+ $con = new LiberalStomp($server);
- if (!empty($frame)) {
- $notice = Notice::staticGet('id', $frame->body);
+ if ($con->connect($this->username, $this->password)) {
+ $this->_log(LOG_INFO, "Connected.");
+ } else {
+ $this->_log(LOG_ERR, 'Failed to connect to queue server');
+ throw new ServerException('Failed to connect to queue server');
+ }
- if (empty($notice)) {
- $this->_log(LOG_WARNING, 'Got ID '. $frame->body .' for non-existent notice in queue '. $queue);
- $this->con->ack($frame);
- } else {
- if ($handler->handle_notice($notice)) {
- $this->_log(LOG_INFO, 'Successfully handled notice '. $notice->id .' posted at ' . $frame->headers['created'] . ' in queue '. $queue);
- $this->con->ack($frame);
- } else {
- $this->_log(LOG_WARNING, 'Failed handling notice '. $notice->id .' posted at ' . $frame->headers['created'] . ' in queue '. $queue);
- // FIXME we probably shouldn't have to do
- // this kind of queue management ourselves
- $this->con->ack($frame);
- $this->enqueue($notice, $queue);
- }
- unset($notice);
+ return $con;
+ }
+
+ /**
+ * Set up all our raw queue subscriptions on the given connection
+ * @param LiberalStomp $con
+ */
+ protected function doSubscribe(LiberalStomp $con)
+ {
+ $host = $con->getServer();
+ foreach ($this->subscriptions() as $sub) {
+ $this->_log(LOG_INFO, "Subscribing to $sub on $host");
+ $con->subscribe($sub);
+ }
+ }
+
+ /**
+ * Grab a full list of stomp-side queue subscriptions.
+ * Will include:
+ * - control broadcast channel
+ * - shared group queues for active groups
+ * - per-handler and per-site breakouts from $config['queue']['breakout']
+ * that are rooted in the active groups.
+ *
+ * @return array of strings
+ */
+ protected function subscriptions()
+ {
+ $subs = array();
+ $subs[] = $this->control;
+
+ foreach ($this->activeGroups as $group) {
+ $subs[] = $this->base . $group;
+ }
+
+ foreach ($this->breakout as $spec) {
+ $parts = explode('/', $spec);
+ if (count($parts) < 2 || count($parts) > 3) {
+ common_log(LOG_ERR, "Bad queue breakout specifier $spec");
+ }
+ if (in_array($parts[0], $this->activeGroups)) {
+ $subs[] = $this->base . $spec;
+ }
+ }
+ return array_unique($subs);
+ }
+
+ /**
+ * Handle and acknowledge an event that's come in through a queue.
+ *
+ * If the queue handler reports failure, the message is requeued for later.
+ * Missing notices or handler classes will drop the message.
+ *
+ * Side effects: in multi-site mode, may reset site configuration to
+ * match the site that queued the event.
+ *
+ * @param StompFrame $frame
+ * @return bool success
+ */
+ protected function handleItem($frame)
+ {
+ $host = $this->cons[$this->defaultIdx]->getServer();
+ $message = unserialize($frame->body);
+ $site = $message['site'];
+ $queue = $message['handler'];
+
+ if ($this->isDeadletter($frame, $message)) {
+ $this->stats('deadletter', $queue);
+ return false;
+ }
+
+ // @fixme detect failing site switches
+ $this->switchSite($site);
+
+ $item = $this->decode($message['payload']);
+ if (empty($item)) {
+ $this->_log(LOG_ERR, "Skipping empty or deleted item in queue $queue from $host");
+ $this->stats('baditem', $queue);
+ return false;
+ }
+ $info = $this->logrep($item) . " posted at " .
+ $frame->headers['created'] . " in queue $queue from $host";
+ $this->_log(LOG_DEBUG, "Dequeued $info");
+
+ $handler = $this->getHandler($queue);
+ if (!$handler) {
+ $this->_log(LOG_ERR, "Missing handler class; skipping $info");
+ $this->stats('badhandler', $queue);
+ return false;
+ }
+
+ try {
+ $ok = $handler->handle($item);
+ } catch (Exception $e) {
+ $this->_log(LOG_ERR, "Exception on queue $queue: " . $e->getMessage());
+ $ok = false;
+ }
+
+ if ($ok) {
+ $this->_log(LOG_INFO, "Successfully handled $info");
+ $this->stats('handled', $queue);
+ } else {
+ $this->_log(LOG_WARNING, "Failed handling $info");
+ // Requeing moves the item to the end of the line for its next try.
+ // @fixme add a manual retry count
+ $this->enqueue($item, $queue);
+ $this->stats('requeued', $queue);
+ }
+
+ return $ok;
+ }
+
+ /**
+ * Check if a redelivered message has been run through enough
+ * that we're going to give up on it.
+ *
+ * @param StompFrame $frame
+ * @param array $message unserialized message body
+ * @return boolean true if we should discard
+ */
+ protected function isDeadLetter($frame, $message)
+ {
+ if (isset($frame->headers['redelivered']) && $frame->headers['redelivered'] == 'true') {
+ // Message was redelivered, possibly indicating a previous failure.
+ $msgId = $frame->headers['message-id'];
+ $site = $message['site'];
+ $queue = $message['handler'];
+ $msgInfo = "message $msgId for $site in queue $queue";
+
+ $deliveries = $this->incDeliveryCount($msgId);
+ if ($deliveries > common_config('queue', 'max_retries')) {
+ $info = "DEAD-LETTER FILE: Gave up after retry $deliveries on $msgInfo";
+
+ $outdir = common_config('queue', 'dead_letter_dir');
+ if ($outdir) {
+ $filename = $outdir . "/$site-$queue-" . rawurlencode($msgId);
+ $info .= ": dumping to $filename";
+ file_put_contents($filename, $message['payload']);
+ }
+
+ common_log(LOG_ERR, $info);
+ return true;
+ } else {
+ common_log(LOG_INFO, "retry $deliveries on $msgInfo");
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Update count of times we've re-encountered this message recently,
+ * triggered when we get a message marked as 'redelivered'.
+ *
+ * Requires a CLI-friendly cache configuration.
+ *
+ * @param string $msgId message-id header from message
+ * @return int number of retries recorded
+ */
+ function incDeliveryCount($msgId)
+ {
+ $count = 0;
+ $cache = common_memcache();
+ if ($cache) {
+ $key = 'statusnet:stomp:message-retries:' . $msgId;
+ $count = $cache->increment($key);
+ if (!$count) {
+ $count = 1;
+ $cache->set($key, $count, null, 3600);
+ $got = $cache->get($key);
+ }
+ }
+ return $count;
+ }
+
+ /**
+ * Process a control signal broadcast.
+ *
+ * @param int $idx connection index
+ * @param array $frame Stomp frame
+ * @return bool true to continue; false to stop further processing.
+ */
+ protected function handleControlSignal($idx, $frame)
+ {
+ $message = trim($frame->body);
+ if (strpos($message, ':') !== false) {
+ list($event, $param) = explode(':', $message, 2);
+ } else {
+ $event = $message;
+ $param = '';
+ }
+
+ $shutdown = false;
+
+ if ($event == 'shutdown') {
+ $this->master->requestShutdown();
+ $shutdown = true;
+ } else if ($event == 'restart') {
+ $this->master->requestRestart();
+ $shutdown = true;
+ } else if ($event == 'update') {
+ $this->updateSiteConfig($param);
+ } else {
+ $this->_log(LOG_ERR, "Ignoring unrecognized control message: $message");
+ }
+ return $shutdown;
+ }
+
+ /**
+ * Switch site, if necessary, and reset current handler assignments
+ * @param string $site
+ */
+ function switchSite($site)
+ {
+ if ($site != StatusNet::currentSite()) {
+ $this->stats('switch');
+ StatusNet::switchSite($site);
+ $this->initialize();
+ }
+ }
+
+ /**
+ * (Re)load runtime configuration for a given site by nickname,
+ * triggered by a broadcast to the 'statusnet-control' topic.
+ *
+ * Configuration changes in database should update, but config
+ * files might not.
+ *
+ * @param array $frame Stomp frame
+ * @return bool true to continue; false to stop further processing.
+ */
+ protected function updateSiteConfig($nickname)
+ {
+ $sn = Status_network::staticGet($nickname);
+ if ($sn) {
+ $this->switchSite($nickname);
+ if (!in_array($nickname, $this->sites)) {
+ $this->addSite();
+ }
+ $this->stats('siteupdate');
+ } else {
+ $this->_log(LOG_ERR, "Ignoring ping for unrecognized new site $nickname");
+ }
+ }
+
+ /**
+ * Combines the queue_basename from configuration with the
+ * group name for this queue to give eg:
+ *
+ * /queue/statusnet/main
+ * /queue/statusnet/main/distrib
+ * /queue/statusnet/xmpp/xmppout/site01
+ *
+ * @param string $queue
+ * @return string
+ */
+ protected function queueName($queue)
+ {
+ $group = $this->queueGroup($queue);
+ $site = StatusNet::currentSite();
+
+ $specs = array("$group/$queue/$site",
+ "$group/$queue");
+ foreach ($specs as $spec) {
+ if (in_array($spec, $this->breakout)) {
+ return $this->base . $spec;
}
+ }
+ return $this->base . $group;
+ }
+
+ /**
+ * Get the breakout mode for the given queue on the current site.
+ *
+ * @param string $queue
+ * @return string one of 'shared', 'handler', 'site'
+ */
+ protected function breakoutMode($queue)
+ {
+ $breakout = common_config('queue', 'breakout');
+ if (isset($breakout[$queue])) {
+ return $breakout[$queue];
+ } else if (isset($breakout['*'])) {
+ return $breakout['*'];
+ } else {
+ return 'shared';
+ }
+ }
+
+ protected function begin($idx)
+ {
+ if ($this->useTransactions) {
+ if (!empty($this->transaction[$idx])) {
+ throw new Exception("Tried to start transaction in the middle of a transaction");
+ }
+ $this->transactionCount[$idx]++;
+ $this->transaction[$idx] = $this->master->id . '-' . $this->transactionCount[$idx] . '-' . time();
+ $this->cons[$idx]->begin($this->transaction[$idx]);
+ }
+ }
- unset($frame);
+ protected function ack($idx, $frame)
+ {
+ if ($this->useTransactions) {
+ if (empty($this->transaction[$idx])) {
+ throw new Exception("Tried to ack but not in a transaction");
+ }
+ $this->cons[$idx]->ack($frame, $this->transaction[$idx]);
+ } else {
+ $this->cons[$idx]->ack($frame);
}
}
- function _queueName($queue)
+ protected function commit($idx)
{
- return common_config('queue', 'queue_basename') . $queue;
+ if ($this->useTransactions) {
+ if (empty($this->transaction[$idx])) {
+ throw new Exception("Tried to commit but not in a transaction");
+ }
+ $this->cons[$idx]->commit($this->transaction[$idx]);
+ $this->transaction[$idx] = null;
+ }
}
- function _log($level, $msg)
+ protected function rollback($idx)
{
- common_log($level, 'StompQueueManager: '.$msg);
+ if ($this->useTransactions) {
+ if (empty($this->transaction[$idx])) {
+ throw new Exception("Tried to rollback but not in a transaction");
+ }
+ $this->cons[$idx]->commit($this->transaction[$idx]);
+ $this->transaction[$idx] = null;
+ }
}
}
+