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

2 files changed, 96 insertions, 0 deletions

diff --git a/plugins/Enjit/README b/plugins/Enjit/README
new file mode 100644
index 000000000..03f989490
--- /dev/null
+++ b/plugins/Enjit/README
@@ -0,0 +1,5 @@
+This doesn't seem to have been functional for a while; can't find other references
+to the enjit configuration or transport enqueuing. Keeping it in case someone
+wants to bring it up to date.
+
+-- brion vibber <brion@status.net> 2009-12-03
diff --git a/plugins/Enjit/enjitqueuehandler.php b/plugins/Enjit/enjitqueuehandler.php
new file mode 100644
index 000000000..f0e706b92
--- /dev/null
+++ b/plugins/Enjit/enjitqueuehandler.php
@@ -0,0 +1,91 @@
+<?php
+/*
+ * StatusNet - the distributed open-source microblogging tool
+ * Copyright (C) 2008, 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);
+}
+
+/**
+ * Queue handler for watching new notices and posting to enjit.
+ * @fixme is this actually being used/functional atm?
+ */
+class EnjitQueueHandler extends QueueHandler
+{
+    function transport()
+    {
+        return 'enjit';
+    }
+
+    function start()
+    {
+        $this->log(LOG_INFO, "Starting EnjitQueueHandler");
+        $this->log(LOG_INFO, "Broadcasting to ".common_config('enjit', 'apiurl'));
+        return true;
+    }
+
+    function handle_notice($notice)
+    {
+
+        $profile = Profile::staticGet($notice->profile_id);
+
+        $this->log(LOG_INFO, "Posting Notice ".$notice->id." from ".$profile->nickname);
+
+        if ( ! $notice->is_local ) {
+            $this->log(LOG_INFO, "Skipping remote notice");
+            return "skipped";
+        }
+
+        #
+        # Build an Atom message from the notice
+        #
+        $noticeurl = common_local_url('shownotice', array('notice' => $notice->id));
+        $msg = $profile->nickname . ': ' . $notice->content;
+
+        $atom  = "<entry xmlns='http://www.w3.org/2005/Atom'>\n";
+        $atom .= "<apisource>".common_config('enjit','source')."</apisource>\n";
+        $atom .= "<source>\n";
+        $atom .= "<title>" . $profile->nickname . " - " . common_config('site', 'name') . "</title>\n";
+        $atom .= "<link href='" . $profile->profileurl . "'/>\n";
+        $atom .= "<link rel='self' type='application/rss+xml' href='" . common_local_url('userrss', array('nickname' => $profile->nickname)) . "'/>\n";
+        $atom .= "<author><name>" . $profile->nickname . "</name></author>\n";
+        $atom .= "<icon>" . $profile->avatarUrl(AVATAR_PROFILE_SIZE) . "</icon>\n";
+        $atom .= "</source>\n";
+        $atom .= "<title>" . htmlspecialchars($msg) . "</title>\n";
+        $atom .= "<summary>" . htmlspecialchars($msg) . "</summary>\n";
+        $atom .= "<link rel='alternate' href='" . $noticeurl . "' />\n";
+        $atom .= "<id>". $notice->uri . "</id>\n";
+        $atom .= "<published>".common_date_w3dtf($notice->created)."</published>\n";
+        $atom .= "<updated>".common_date_w3dtf($notice->modified)."</updated>\n";
+        $atom .= "</entry>\n";
+
+        $url  = common_config('enjit', 'apiurl') . "/submit/". common_config('enjit','apikey');
+        $data = array(
+            'msg' => $atom,
+        );
+
+        #
+        # POST the message to $config['enjit']['apiurl']
+        #
+        $request = HTTPClient::start();
+        $response = $request->post($url, null, $data);
+
+        return $response->isOk();
+    }
+
+}