gnu-social/lib/statusnet.php
Brion Vibber ec145b73fc Major refactoring of queue handlers to support running multiple sites in one daemon.
Key changes:
* Initialization code moved from common.php to StatusNet class;
  can now switch configurations during runtime.
* As a consequence, configuration files must now be idempotent...
  Be careful with constant, function or class definitions.
* Control structure for daemons/QueueManager/QueueHandler has been refactored;
  the run loop is now managed by IoMaster run via scripts/queuedaemon.php
  IoManager subclasses are woken to handle socket input or polling, and may
  cover multiple sites.
* Plugins can implement notice queue handlers more easily by registering a
  QueueHandler class; no more need to add a daemon.

The new QueueDaemon runs from scripts/queuedaemon.php:

* This replaces most of the old *handler.php scripts; they've been refactored
  to the bare handler classes.
* Spawns multiple child processes to spread load; defaults to CPU count on
  Linux and Mac OS X systems, or override with --threads=N
* When multithreaded, child processes are automatically respawned on failure.
* Threads gracefully shut down and restart when passing a soft memory limit
  (defaults to 90% of memory_limit), limiting damage from memory leaks.
* Support for UDP-based monitoring: http://www.gitorious.org/snqmon

Rough control flow diagram:
QueueDaemon -> IoMaster -> IoManager
                           QueueManager [listen or poll] -> QueueHandler
                           XmppManager [ping & keepalive]
                           XmppConfirmManager [poll updates]

Todo:

* Respawning features not currently available running single-threaded.
* When running single-site, configuration changes aren't picked up.
* New sites or config changes affecting queue subscriptions are not yet
  handled without a daemon restart.
* SNMP monitoring output to integrate with general tools (nagios, ganglia)
* Convert XMPP confirmation message sends to use stomp queue instead of polling
* Convert xmppdaemon.php to IoManager?
* Convert Twitter status, friends import polling daemons to IoManager
* Clean up some error reporting and failure modes
* May need to adjust queue priorities for best perf in backlog/flood cases

Detailed code history available in my daemon-work branch:
http://www.gitorious.org/~brion/statusnet/brion-fixes/commits/daemon-work
2010-01-12 20:45:09 -08:00

296 lines
9.4 KiB
PHP

<?php
/*
* StatusNet - the distributed open-source microblogging tool
* Copyright (C) 2009, 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('STATUSNET') && !defined('LACONICA')) { exit(1); }
global $config, $_server, $_path;
/**
* Global configuration setup and management.
*/
class StatusNet
{
protected static $have_config;
/**
* Configure and instantiate a plugin into the current configuration.
* Class definitions will be loaded from standard paths if necessary.
* Note that initialization events won't be fired until later.
*
* @param string $name class name & plugin file/subdir name
* @param array $attrs key/value pairs of public attributes to set on plugin instance
*
* @throws ServerException if plugin can't be found
*/
public static function addPlugin($name, $attrs = null)
{
$name = ucfirst($name);
$pluginclass = "{$name}Plugin";
if (!class_exists($pluginclass)) {
$files = array("local/plugins/{$pluginclass}.php",
"local/plugins/{$name}/{$pluginclass}.php",
"local/{$pluginclass}.php",
"local/{$name}/{$pluginclass}.php",
"plugins/{$pluginclass}.php",
"plugins/{$name}/{$pluginclass}.php");
foreach ($files as $file) {
$fullpath = INSTALLDIR.'/'.$file;
if (@file_exists($fullpath)) {
include_once($fullpath);
break;
}
}
if (!class_exists($pluginclass)) {
throw new ServerException(500, "Plugin $name not found.");
}
}
$inst = new $pluginclass();
if (!empty($attrs)) {
foreach ($attrs as $aname => $avalue) {
$inst->$aname = $avalue;
}
}
return true;
}
/**
* Initialize, or re-initialize, StatusNet global configuration
* and plugins.
*
* If switching site configurations during script execution, be
* careful when working with leftover objects -- global settings
* affect many things and they may not behave as you expected.
*
* @param $server optional web server hostname for picking config
* @param $path optional URL path for picking config
* @param $conffile optional configuration file path
*
* @throws NoConfigException if config file can't be found
*/
public static function init($server=null, $path=null, $conffile=null)
{
StatusNet::initDefaults($server, $path);
StatusNet::loadConfigFile($conffile);
// Load settings from database; note we need autoload for this
Config::loadSettings();
self::initPlugins();
}
/**
* Fire initialization events for all instantiated plugins.
*/
protected static function initPlugins()
{
// Load default plugins
foreach (common_config('plugins', 'default') as $name => $params) {
if (is_null($params)) {
addPlugin($name);
} else if (is_array($params)) {
if (count($params) == 0) {
addPlugin($name);
} else {
$keys = array_keys($params);
if (is_string($keys[0])) {
addPlugin($name, $params);
} else {
foreach ($params as $paramset) {
addPlugin($name, $paramset);
}
}
}
}
}
// XXX: if plugins should check the schema at runtime, do that here.
if (common_config('db', 'schemacheck') == 'runtime') {
Event::handle('CheckSchema');
}
// Give plugins a chance to initialize in a fully-prepared environment
Event::handle('InitializePlugin');
}
/**
* Quick-check if configuration has been established.
* Useful for functions which may get used partway through
* initialization to back off from fancier things.
*
* @return bool
*/
public function haveConfig()
{
return self::$have_config;
}
/**
* Build default configuration array
* @return array
*/
protected static function defaultConfig()
{
global $_server, $_path;
require(INSTALLDIR.'/lib/default.php');
return $default;
}
/**
* Establish default configuration based on given or default server and path
* Sets global $_server, $_path, and $config
*/
protected static function initDefaults($server, $path)
{
global $_server, $_path, $config;
Event::clearHandlers();
// try to figure out where we are. $server and $path
// can be set by including module, else we guess based
// on HTTP info.
if (isset($server)) {
$_server = $server;
} else {
$_server = array_key_exists('SERVER_NAME', $_SERVER) ?
strtolower($_SERVER['SERVER_NAME']) :
null;
}
if (isset($path)) {
$_path = $path;
} else {
$_path = (array_key_exists('SERVER_NAME', $_SERVER) && array_key_exists('SCRIPT_NAME', $_SERVER)) ?
self::_sn_to_path($_SERVER['SCRIPT_NAME']) :
null;
}
// Set config values initially to default values
$default = self::defaultConfig();
$config = $default;
// default configuration, overwritten in config.php
// Keep DB_DataObject's db config synced to ours...
$config['db'] = &PEAR::getStaticProperty('DB_DataObject','options');
$config['db'] = $default['db'];
// Backward compatibility
$config['site']['design'] =& $config['design'];
if (function_exists('date_default_timezone_set')) {
/* Work internally in UTC */
date_default_timezone_set('UTC');
}
}
protected function _sn_to_path($sn)
{
$past_root = substr($sn, 1);
$last_slash = strrpos($past_root, '/');
if ($last_slash > 0) {
$p = substr($past_root, 0, $last_slash);
} else {
$p = '';
}
return $p;
}
/**
* Load the default or specified configuration file.
* Modifies global $config and may establish plugins.
*
* @throws NoConfigException
*/
protected function loadConfigFile($conffile=null)
{
global $_server, $_path, $config;
// From most general to most specific:
// server-wide, then vhost-wide, then for a path,
// finally for a dir (usually only need one of the last two).
if (isset($conffile)) {
$config_files = array($conffile);
} else {
$config_files = array('/etc/statusnet/statusnet.php',
'/etc/statusnet/laconica.php',
'/etc/laconica/laconica.php',
'/etc/statusnet/'.$_server.'.php',
'/etc/laconica/'.$_server.'.php');
if (strlen($_path) > 0) {
$config_files[] = '/etc/statusnet/'.$_server.'_'.$_path.'.php';
$config_files[] = '/etc/laconica/'.$_server.'_'.$_path.'.php';
}
$config_files[] = INSTALLDIR.'/config.php';
}
self::$have_config = false;
foreach ($config_files as $_config_file) {
if (@file_exists($_config_file)) {
include($_config_file);
self::$have_config = true;
}
}
if (!self::$have_config) {
throw new NoConfigException("No configuration file found.",
$config_files);
}
// Fixup for statusnet.ini
$_db_name = substr($config['db']['database'], strrpos($config['db']['database'], '/') + 1);
if ($_db_name != 'statusnet' && !array_key_exists('ini_'.$_db_name, $config['db'])) {
$config['db']['ini_'.$_db_name] = INSTALLDIR.'/classes/statusnet.ini';
}
// Backwards compatibility
if (array_key_exists('memcached', $config)) {
if ($config['memcached']['enabled']) {
addPlugin('Memcache', array('servers' => $config['memcached']['server']));
}
if (!empty($config['memcached']['base'])) {
$config['cache']['base'] = $config['memcached']['base'];
}
}
}
}
class NoConfigException extends Exception
{
public $config_files;
function __construct($msg, $config_files) {
parent::__construct($msg);
$this->config_files = $config_files;
}
}