<?php
/*
* StatusNet - the distributed open-source microblogging tool
* Copyright (C) 2010, StatusNet, Inc.
*
* 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/>.
*/
if (!defined('GNUSOCIAL')) { exit(1); }
/**
* WebSub (previously PuSH) feed subscription record
* @package Hub
* @author Brion Vibber <brion@status.net>
*/
class HubSub extends Managed_DataObject
{
public $__table = 'hubsub';
public $hashkey; // sha1(topic . '|' . $callback); (topic, callback) key is too long for myisam in utf8
public $topic; // varchar(191) not 255 because utf8mb4 takes more space
public $callback; // varchar(191) not 255 because utf8mb4 takes more space
public $secret;
public $sub_start;
public $sub_end;
public $created;
public $modified;
static function hashkey($topic, $callback)
{
return sha1($topic . '|' . $callback);
}
public static function getByHashkey($topic, $callback)
{
return self::getKV('hashkey', self::hashkey($topic, $callback));
}
public static function schemaDef()
{
return array(
'fields' => array(
'hashkey' => array('type' => 'char', 'not null' => true, 'length' => 40, 'description' => 'HubSub hashkey'),
'topic' => array('type' => 'varchar', 'not null' => true, 'length' => 191, 'description' => 'HubSub topic'),
'callback' => array('type' => 'varchar', 'not null' => true, 'length' => 191, 'description' => 'HubSub callback'),
'secret' => array('type' => 'text', 'description' => 'HubSub stored secret'),
'sub_start' => array('type' => 'datetime', 'description' => 'subscription start'),
'sub_end' => array('type' => 'datetime', 'description' => 'subscription end'),
'errors' => array('type' => 'integer', 'not null' => true, 'default' => 0, 'description' => 'Queue handling error count, is reset on success.'),
'error_start' => array('type' => 'datetime', 'default' => null, 'description' => 'time of first error since latest success, should be null if no errors have been counted'),
'last_error' => array('type' => 'datetime', 'default' => null, 'description' => 'time of last failure, if ever'),
'last_error_msg' => array('type' => 'text', 'default' => null, 'description' => 'Last error _message_'),
'created' => array('type' => 'datetime', 'not null' => true, 'description' => 'date this record was created'),
'modified' => array('type' => 'timestamp', 'not null' => true, 'description' => 'date this record was modified'),
),
'primary key' => array('hashkey'),
'indexes' => array(
'hubsub_callback_idx' => array('callback'),
'hubsub_topic_idx' => array('topic'),
),
);
}
function getErrors()
{
return intval($this->errors);
}
// $msg is only set if $error_count is 0
function setErrors($error_count, $msg=null)
{
assert(is_int($error_count));
if (!is_int($error_count) || $error_count < 0) {
common_log(LOG_ERR, 'HubSub->setErrors was given a bad value: '._ve($error_count));
throw new ServerException('HubSub error count must be an integer higher or equal to 0.');
}
$orig = clone($this);
$now = common_sql_now();
if ($error_count === 1) {
// Record when the errors started
$this->error_start = $now;
}
if ($error_count > 0) {
// Record this error's occurrence in time
$this->last_error = $now;
$this->last_error_msg = $msg;
} else {
$this->error_start = null;
$this->last_error = null;
$this->last_error_msg = null;
}
$this->errors = $error_count;
$this->update($orig);
}
function resetErrors()
{
return $this->setErrors(0);
}
function incrementErrors($msg=null)
{
return $this->setErrors($this->getErrors()+1, $msg);
}
/**
* Validates a requested lease length, sets length plus
* subscription start & end dates.
*
* Does not save to database -- use before insert() or update().
*
* @param int $length in seconds
*/
function setLease($length)
{
common_debug('WebSub hub got requested lease_seconds=='._ve($length));
assert(is_int($length));
$min = 86400; // 3600*24 (one day)
$max = 86400 * 30;
if ($length == 0) {
// We want to garbage collect dead subscriptions!
$length = $max;
} elseif( $length < $min) {
$length = $min;
} else if ($length > $max) {
$length = $max;
}
common_debug('WebSub hub after sanitation: lease_seconds=='._ve($length));
$this->sub_start = common_sql_now();
$this->sub_end = common_sql_date(time() + $length);
}
function getLeaseTime()
{
if (empty($this->sub_start) || empty($this->sub_end)) {
return null;
}
$length = strtotime($this->sub_end) - strtotime($this->sub_start);
assert($length > 0);
return $length;
}
function getLeaseRemaining()
{
if (empty($this->sub_end)) {
return null;
}
return strtotime($this->sub_end) - time();
}
/**
* Schedule a future verification ping to the subscriber.
* If queues are disabled, will be immediate.
*
* @param string $mode 'subscribe' or 'unsubscribe'
* @param string $token hub.verify_token value, if provided by client
*/
function scheduleVerify($mode, $token=null, $retries=null)
{
if ($retries === null) {
$retries = intval(common_config('ostatus', 'hub_retries'));
}
$data = array('sub' => clone($this),
'mode' => $mode,
'token' => $token, // let's put it in there if remote uses PuSH <0.4
'retries' => $retries);
$qm = QueueManager::get();
$qm->enqueue($data, 'hubconf');
}
public function getTopic()
{
return $this->topic;
}
/**
* Send a verification ping to subscriber, and if confirmed apply the changes.
* This may create, update, or delete the database record.
*
* @param string $mode 'subscribe' or 'unsubscribe'
* @param string $token hub.verify_token value, if provided by client
* @throws ClientException on failure
*/
function verify($mode, $token=null)
{
assert($mode == 'subscribe' || $mode == 'unsubscribe');
$challenge = common_random_hexstr(32);
$params = array('hub.mode' => $mode,
'hub.topic' => $this->getTopic(),
'hub.challenge' => $challenge);
if ($mode == 'subscribe') {
$params['hub.lease_seconds'] = $this->getLeaseTime();
}
if ($token !== null) { // TODO: deprecated in PuSH 0.4
$params['hub.verify_token'] = $token; // let's put it in there if remote uses PuSH <0.4
}
// Any existing query string parameters must be preserved
$url = $this->callback;
if (strpos($url, '?') !== false) {
$url .= '&';
} else {
$url .= '?';
}
$url .= http_build_query($params, '', '&');
$request = new HTTPClient();
$response = $request->get($url);
$status = $response->getStatus();
if ($status >= 200 && $status < 300) {
common_log(LOG_INFO, "Verified {$mode} of {$this->callback}:{$this->getTopic()}");
} else {
// TRANS: Client exception. %s is a HTTP status code.
throw new ClientException(sprintf(_m('Hub subscriber verification returned HTTP %s.'),$status));
}
$old = HubSub::getByHashkey($this->getTopic(), $this->callback);
if ($mode == 'subscribe') {
if ($old instanceof HubSub) {
$this->update($old);
} else {
$ok = $this->insert();
}
} else if ($mode == 'unsubscribe') {
if ($old instanceof HubSub) {
$old->delete();
} else {
// That's ok, we're already unsubscribed.
}
}
}
// set the hashkey automagically on insert
protected function onInsert()
{
$this->setHashkey();
$this->created = common_sql_now();
$this->modified = common_sql_now();
}
// update the hashkey automagically if needed
protected function onUpdateKeys(Managed_DataObject $orig)
{
if ($this->topic !== $orig->topic || $this->callback !== $orig->callback) {
$this->setHashkey();
}
}
protected function setHashkey()
{
$this->hashkey = self::hashkey($this->topic, $this->callback);
}
/**
* Schedule delivery of a 'fat ping' to the subscriber's callback
* endpoint. If queues are disabled, this will run immediately.
*
* @param string $atom well-formed Atom feed
* @param int $retries optional count of retries if POST fails; defaults to hub_retries from config or 0 if unset
*/
function distribute($atom, $retries=null)
{
if ($retries === null) {
$retries = intval(common_config('ostatus', 'hub_retries'));
}
$data = array('topic' => $this->getTopic(),
'callback' => $this->callback,
'atom' => $atom,
'retries' => $retries);
common_log(LOG_INFO, sprintf('Queuing WebSub: %s to %s', _ve($data['topic']), _ve($data['callback'])));
$qm = QueueManager::get();
$qm->enqueue($data, 'hubout');
}
/**
* Queue up a large batch of pushes to multiple subscribers
* for this same topic update.
*
* If queues are disabled, this will run immediately.
*
* @param string $atom well-formed Atom feed
* @param array $pushCallbacks list of callback URLs
*/
function bulkDistribute($atom, array $pushCallbacks)
{
if (empty($pushCallbacks)) {
common_log(LOG_ERR, 'Callback list empty for bulkDistribute.');
return false;
}
$data = array('atom' => $atom,
'topic' => $this->getTopic(),
'pushCallbacks' => $pushCallbacks);
common_log(LOG_INFO, "Queuing WebSub batch: {$this->getTopic()} to ".count($pushCallbacks)." sites");
$qm = QueueManager::get();
$qm->enqueue($data, 'hubprep');
return true;
}
/**
* @return boolean true/false for HTTP response
* @throws Exception for lower-than-HTTP errors (such as NS lookup failure, connection refused...)
*/
public static function pushAtom($topic, $callback, $atom, $secret=null, $hashalg='sha1')
{
$headers = array('Content-Type: application/atom+xml');
if ($secret) {
$hmac = hash_hmac($hashalg, $atom, $secret);
$headers[] = "X-Hub-Signature: {$hashalg}={$hmac}";
} else {
$hmac = '(none)';
}
common_log(LOG_INFO, sprintf('About to WebSub-push feed to %s for %s, HMAC %s', _ve($callback), _ve($topic), _ve($hmac)));
$request = new HTTPClient();
$request->setConfig(array('follow_redirects' => false));
$request->setBody($atom);
// This will throw exception on non-HTTP failures
try {
$response = $request->post($callback, $headers);
} catch (Exception $e) {
common_debug(sprintf('WebSub callback to %s for %s failed with exception %s: %s', _ve($callback), _ve($topic), _ve(get_class($e)), _ve($e->getMessage())));
throw $e;
}
return $response->isOk();
}
/**
* Send a 'fat ping' to the subscriber's callback endpoint
* containing the given Atom feed chunk.
*
* Determination of which feed items to send should be done at
* a higher level; don't just shove in a complete feed!
*
* FIXME: Add 'failed' incremental count.
*
* @param string $atom well-formed Atom feed
* @return boolean Whether the PuSH was accepted or not.
* @throws Exception (HTTP or general)
*/
function push($atom)
{
try {
$success = self::pushAtom($this->getTopic(), $this->callback, $atom, $this->secret);
if ($success) {
return true;
} elseif ('https' === parse_url($this->callback, PHP_URL_SCHEME)) {
// Already HTTPS, no need to check remote http/https migration issues
return false;
}
// if pushAtom returned false and we didn't try an HTTPS endpoint,
// let's try HTTPS too (assuming only http:// and https:// are used ;))
} catch (Exception $e) {
if ('https' === parse_url($this->callback, PHP_URL_SCHEME)) {
// Already HTTPS, no need to check remote http/https migration issues
throw $e;
}
}
// We failed the WebSub push, but it might be that the remote site has changed their configuration to HTTPS
common_debug('WebSub HTTPSFIX: push failed, so we need to see if it can be the remote http->https migration issue.');
// XXX: DO NOT trust a Location header here, _especially_ from 'http' protocols,
// but not 'https' either at least if we don't do proper CA verification. Trust that
// the most common change here is simply switching 'http' to 'https' and we will
// solve 99% of all of these issues for now. There should be a proper mechanism
// if we want to change the callback URLs, preferrably just manual resubscriptions
// from the remote side, combined with implemented WebSub subscription timeouts.
// Test if the feed callback for this node has already been migrated to HTTPS in our database
// (otherwise we'd get collisions when inserting it further down)
$httpscallback = preg_replace('/^http/', 'https', $this->callback, 1);
$alreadyreplaced = self::getByHashKey($this->getTopic(), $httpscallback);
if ($alreadyreplaced instanceof HubSub) {
// Let's remove the old HTTP callback object.
$this->delete();
// XXX: I think this means we might lose a message or two when
// remote side migrates to HTTPS because we only try _once_
// for _one_ WebSub push. The rest of the posts already
// stored in our queue (if any) will not find a HubSub
// object. This could maybe be fixed by handling migration
// in HubOutQueueHandler while handling the item there.
common_debug('WebSub HTTPSFIX: Pushing Atom to HTTPS callback instead of HTTP, because of switch to HTTPS since enrolled in queue.');
return self::pushAtom($this->getTopic(), $httpscallback, $atom, $this->secret);
}
common_debug('WebSub HTTPSFIX: callback to '._ve($this->callback).' for '._ve($this->getTopic()).' trying HTTPS callback: '._ve($httpscallback));
$success = self::pushAtom($this->getTopic(), $httpscallback, $atom, $this->secret);
if ($success) {
// Yay, we made a successful push to https://, let's remember this in the future!
$orig = clone($this);
$this->callback = $httpscallback;
// NOTE: hashkey will be set in $this->onUpdateKeys($orig) through updateWithKeys
$this->updateWithKeys($orig);
return true;
}
// If there have been any exceptions thrown before, they're handled
// higher up. This function's return value is just whether the WebSub
// push was accepted or not.
return $success;
}
}