gnu-social/lib/stompqueuemanager.php
Brion Vibber ce6be4f836 Queues: redid the breakout control model so we can start up and subscribe to queues without running through the complete site list, which is ok at 1k sites but too slow at 10k.
All breakout queues that we're going to need to listen to now need to be explicitly listed in $config['queue']['breakout'].

Until XMPP is moved to component model, this setting will let the individual processes work with their own queues:
$config['queue']['breakout'][] = 'xmpp/xmppout/' . $config['site']['nickname'];
2010-02-17 16:49:00 -08:00

739 lines
23 KiB
PHP

<?php
/**
* StatusNet, the distributed open-source microblogging tool
*
* Abstract class for queue managers
*
* PHP version 5
*
* LICENCE: This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* @category QueueManager
* @package StatusNet
* @author Evan Prodromou <evan@status.net>
* @author Sarven Capadisli <csarven@status.net>
* @copyright 2009 StatusNet, Inc.
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://status.net/
*/
require_once 'Stomp.php';
require_once 'Stomp/Exception.php';
class StompQueueManager extends QueueManager
{
protected $servers;
protected $username;
protected $password;
protected $base;
protected $control;
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()
{
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');
}
/**
* Tell the i/o master we only need a single instance to cover
* all sites running in this process.
*/
public static function multiSite()
{
return IoManager::INSTANCE_PER_PROCESS;
}
/**
* 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;
}
}
/**
* 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)
{
$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);
$props = array('created' => common_sql_now());
if ($this->isPersistent($queue)) {
$props['persistent'] = 'true';
}
$con = $this->cons[$idx];
$host = $con->getServer();
$target = $this->queueName($queue);
$result = $con->send($target, $msg, $props);
if (!$result) {
$this->_log(LOG_ERR, "Error sending $rep to $queue queue on $host $target");
return false;
}
$this->_log(LOG_DEBUG, "complete remote queueing $rep for $queue on $host $target");
$this->stats('enqueued', $queue);
return true;
}
/**
* 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)
{
$mode = common_config('queue', 'stomp_persistent');
if (is_array($mode)) {
return in_array($queue, $mode);
} else {
return (bool)$mode;
}
}
/**
* 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;
}
/**
* 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");
}
/**
* 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;
$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;
}
/**
* 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;
}
/**
* 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);
$this->_connectAll();
foreach ($this->cons as $i => $con) {
if ($con) {
$this->doSubscribe($con);
$this->begin($i);
}
}
return true;
}
/**
* 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;
}
/**
* 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);
}
}
/**
* 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();
}
$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;
$this->doSubscribe($con);
$this->begin($idx);
} else {
// Try again later...
$this->disconnect[$idx] = time();
}
}
protected function _doConnect($server)
{
$this->_log(LOG_INFO, "Connecting to '$server' as '$this->username'...");
$con = new LiberalStomp($server);
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');
}
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]);
}
}
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($frame);
}
}
protected function commit($idx)
{
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;
}
}
protected function rollback($idx)
{
if ($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;
}
}
}