JavaScript and other changes to make realtime_channel management work

plugins/Realtime/RealtimePlugin.php

@@ -93,16 +93,24 @@ class RealtimePlugin extends Plugin
      */
     function onRouterInitialized($m)
     {
-        // Discovery actions
+        $m->connect('main/channel/:channelkey/keepalive',
-        $m->connect('main/channel/:channel_key/keepalive',
+                    array('action' => 'keepalivechannel'),
-                    array('action' => 'keepalivechannel'));
+                    array('channelkey' => '[a-z0-9]{32}'));
-        $m->connect('main/channel/:channel_key/close',
+        $m->connect('main/channel/:channelkey/close',
-                    array('action' => 'closechannel'));
+                    array('action' => 'closechannel'),
+                    array('channelkey' => '[a-z0-9]{32}'));
+        return true;
     }
 
     function onEndShowScripts($action)
     {
-        $timeline = $this->_getTimeline($action);
+        $channel = $this->_getChannel($action);
+
+        if (empty($channel)) {
+            return true;
+        }
+
+        $timeline = $this->_pathToChannel(array($channel->channel_key));
 
         // If there's not a timeline on this page,
         // just return true
@@ -137,7 +145,9 @@ class RealtimePlugin extends Plugin
         }
         else {
             $pluginPath = common_path('plugins/Realtime/');
-            $realtimeUI = ' RealtimeUpdate.initActions("'.$url.'", "'.$timeline.'", "'. $pluginPath .'");';
+            $keepalive = common_local_url('keepalivechannel', array('channelkey' => $channel->channel_key));
+            $close = common_local_url('closechannel', array('channelkey' => $channel->channel_key));
+            $realtimeUI = ' RealtimeUpdate.initActions("'.$url.'", "'.$timeline.'", "'. $pluginPath .'", "'.$keepalive.'", "'.$close.'"); ';
         }
 
         $script = ' $(document).ready(function() { '.
@@ -431,7 +441,18 @@ class RealtimePlugin extends Plugin
         return '';
     }
 
+
     function _getTimeline($action)
+    {
+        $channel = $this->_getChannel($action);
+        if (empty($channel)) {
+            return null;
+        }
+
+        return $this->_pathToChannel(array($channel->channel_key));
+    }
+
+    function _getChannel($action)
     {
         $timeline = null;
 		$arg1     = null;
@@ -481,11 +502,7 @@ class RealtimePlugin extends Plugin
 												$arg1,
 												$arg2);
 
-		if (!empty($channel)) {
+        return $channel;
-			$timeline = $this->_pathToChannel(array($channel->channel_key));
-		}
-				
-        return $timeline;
     }
     
     function onStartReadWriteTables(&$alwaysRW, &$rwdb)

plugins/Realtime/Realtime_channel.php

@@ -58,6 +58,7 @@ class Realtime_channel extends Managed_DataObject
     public $arg1;          // argument
     public $arg2;          // argument, usually null
     public $channel_key;   // 128-bit shared secret key
+    public $audience;      // listener count
     public $created;	   // created date
     public $modified;      // modified date
 
@@ -117,6 +118,10 @@ class Realtime_channel extends Managed_DataObject
 			    			   'length' => 32,
 			    			   'not null' => true,
 			    			   'description' => 'shared secret key for this channel'),
+			    'audience' => array('type' => 'integer',
+                                    'not null' => true,
+                                    'default' => 0,
+                                    'description' => 'reference count'),
                 'created' => array('type' => 'datetime',
 				   				   'not null' => true,
 				   				   'description' => 'date this record was created'),
@@ -144,6 +149,7 @@ class Realtime_channel extends Managed_DataObject
     	$channel->action  = $action;
     	$channel->arg1    = $arg1;
     	$channel->arg2    = $arg2;
+    	$channel->audience  = 1;
     	
     	$channel->channel_key = common_good_rand(16); // 128-bit key, 32 hex chars
     	
@@ -230,18 +236,40 @@ class Realtime_channel extends Managed_DataObject
     	}
     	
     	if ($channel->find(true)) {
-            $channel->touch();
+            $channel->increment();
     		return $channel;
     	} else {
     		return null;
     	}
     }
 
+    function increment()
+    {
+        // XXX: race
+        $orig = clone($this);
+        $this->audience++;
+        $this->modified = common_sql_now();
+        $this->update($orig);
+    }
+
     function touch()
     {
-   		// Touch it!
+        // XXX: race
         $orig = clone($this);
         $this->modified = common_sql_now();
         $this->update($orig);
     }
+
+    function decrement()
+    {
+        // XXX: race
+        if ($this->audience == 1) {
+            $this->delete();
+        } else {
+            $orig = clone($this);
+            $this->audience--;
+            $this->modified = common_sql_now();
+            $this->update($orig);
+        }
+    }
 }

plugins/Realtime/closechannel.php

@@ -66,7 +66,7 @@ class ClosechannelAction extends Action
             throw new ClientException(_m('You have to POST it.'));
         }
 
-        $this->channelKey = $this->trimmed('channel_key');
+        $this->channelKey = $this->trimmed('channelkey');
 
         if (empty($this->channelKey)) {
             throw new ClientException(_m('No channel key argument.'));
@@ -91,7 +91,7 @@ class ClosechannelAction extends Action
 
     function handle($argarray=null)
     {
-        $this->channel->delete();
+        $this->channel->decrement();
 
         header('HTTP/1.1 204 No Content');
 

plugins/Realtime/keepalivechannel.php

@@ -66,7 +66,7 @@ class KeepalivechannelAction extends Action
             throw new ClientException(_m('You have to POST it.'));
         }
 
-        $this->channelKey = $this->trimmed('channel_key');
+        $this->channelKey = $this->trimmed('channelkey');
 
         if (empty($this->channelKey)) {
             throw new ClientException(_m('No channel key argument.'));

plugins/Realtime/realtimeupdate.js

@@ -1,6 +1,6 @@
 /*
  * StatusNet - a distributed open-source microblogging tool
- * Copyright (C) 2008, StatusNet, Inc.
+ * Copyright (C) 2009-2011, StatusNet, Inc.
  *
  * Add a notice encoded as JSON into the current timeline
  *
@@ -21,7 +21,7 @@
  * @package   StatusNet
  * @author    Evan Prodromou <evan@status.net>
  * @author    Sarven Capadisli <csarven@status.net>
- * @copyright 2009 StatusNet, Inc.
+ * @copyright 2009-2011 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/
  */
@@ -45,6 +45,8 @@
 RealtimeUpdate = {
      _userid: 0,
      _showurl: '',
+     _keepaliveurl: '',
+     _closeurl: '',
      _updatecounter: 0,
      _maxnotices: 50,
      _windowhasfocus: true,
@@ -390,11 +392,28 @@ RealtimeUpdate = {
       *
       * @access private
       */
-     initActions: function(url, timeline, path)
+    initActions: function(url, timeline, path, keepaliveurl, closeurl)
      {
         $('#notices_primary').prepend('<ul id="realtime_actions"><li id="realtime_playpause"></li><li id="realtime_timeline"></li></ul>');
 
         RealtimeUpdate._pluginPath = path;
+        RealtimeUpdate._keepaliveurl = keepaliveurl;
+        RealtimeUpdate._closeurl = closeurl;
+
+
+	 // On unload, let the server know we're no longer listening
+         $(window).unload(function() {
+            $.ajax({
+                type: 'POST',
+                url: RealtimeUpdate._closeurl});
+	 });
+
+	setInterval(function() {
+            $.ajax({
+                type: 'POST',
+                url: RealtimeUpdate._keepaliveurl});
+	    
+	}, 15 * 60 * 1000 ); // every 15 min; timeout in 30 min
 
         RealtimeUpdate.initPlayPause();
         RealtimeUpdate.initAddPopup(url, timeline, RealtimeUpdate._pluginPath);