* implemented STOMP support for external message queueing systems

* (ticket-724)
* included PHP STOMP libraries (http://code.google.com/p/stompcli/)

9 files changed, 980 insertions, 20 deletions

diff --git a/config.php.sample b/config.php.sample
index a2c5801f4..cc2e4c3c1 100644
--- a/config.php.sample
+++ b/config.php.sample
@@ -112,6 +112,14 @@ $config['sphinx']['port'] = 3312;
 #background. See the README for details.
 #$config['queue']['enabled'] = true;
 
+#Queue subsystem
+#subsystems: internal (default) or stomp
+#using stomp requires an external message queue server
+#$config['queue']['subsystem'] = 'stomp';
+#$config['queue']['stomp_server'] = 'tcp://localhost:61613';
+#use different queue_basename for each laconica instance managed by the server
+#$config['queue']['queue_basename'] = 'laconica';
+
 #The following customise the behaviour of the various daemons:
 #$config['daemon']['piddir'] = '/var/run';
 #$config['daemon']['user'] = false;
diff --git a/extlib/Stomp.php b/extlib/Stomp.php
new file mode 100644
index 000000000..9e1c97b3b
--- /dev/null
+++ b/extlib/Stomp.php
@@ -0,0 +1,594 @@
+<?php
+/**
+ *
+ * Copyright 2005-2006 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* vim: set expandtab tabstop=3 shiftwidth=3: */
+
+require_once 'Stomp/Frame.php';
+
+/**
+ * A Stomp Connection
+ *
+ *
+ * @package Stomp
+ * @author Hiram Chirino <hiram@hiramchirino.com>
+ * @author Dejan Bosanac <dejan@nighttale.net> 
+ * @author Michael Caplan <mcaplan@labnet.net>
+ * @version $Revision: 43 $
+ */
+class Stomp
+{
+    /**
+     * Perform request synchronously
+     *
+     * @var boolean
+     */
+    public $sync = false;
+
+    /**
+     * Default prefetch size
+     *
+     * @var int
+     */
+	public $prefetchSize = 1;
+    
+	/**
+     * Client id used for durable subscriptions
+     *
+     * @var string
+     */
+	public $clientId = null;
+    
+    protected $_brokerUri = null;
+    protected $_socket = null;
+    protected $_hosts = array();
+    protected $_params = array();
+    protected $_subscriptions = array();
+    protected $_defaultPort = 61613;
+    protected $_currentHost = - 1;
+    protected $_attempts = 10;
+    protected $_username = '';
+    protected $_password = '';
+    protected $_sessionId;
+    protected $_read_timeout_seconds = 60;
+    protected $_read_timeout_milliseconds = 0;
+    
+    /**
+     * Constructor
+     *
+     * @param string $brokerUri Broker URL
+     * @throws Stomp_Exception
+     */
+    public function __construct ($brokerUri)
+    {
+        $this->_brokerUri = $brokerUri;
+        $this->_init();
+    }
+    /**
+     * Initialize connection
+     *
+     * @throws Stomp_Exception
+     */
+    protected function _init ()
+    {
+        $pattern = "|^(([a-zA-Z]+)://)+\(*([a-zA-Z0-9\.:/i,-]+)\)*\??([a-zA-Z0-9=]*)$|i";
+        if (preg_match($pattern, $this->_brokerUri, $regs)) {
+            $scheme = $regs[2];
+            $hosts = $regs[3];
+            $params = $regs[4];
+            if ($scheme != "failover") {
+                $this->_processUrl($this->_brokerUri);
+            } else {
+                $urls = explode(",", $hosts);
+                foreach ($urls as $url) {
+                    $this->_processUrl($url);
+                }
+            }
+            if ($params != null) {
+                parse_str($params, $this->_params);
+            }
+        } else {
+            require_once 'Stomp/Exception.php';
+            throw new Stomp_Exception("Bad Broker URL {$this->_brokerUri}");
+        }
+    }
+    /**
+     * Process broker URL
+     *
+     * @param string $url Broker URL
+     * @throws Stomp_Exception
+     * @return boolean
+     */
+    protected function _processUrl ($url)
+    {
+        $parsed = parse_url($url);
+        if ($parsed) {
+            array_push($this->_hosts, array($parsed['host'] , $parsed['port'] , $parsed['scheme']));
+        } else {
+            require_once 'Stomp/Exception.php';
+            throw new Stomp_Exception("Bad Broker URL $url");
+        }
+    }
+    /**
+     * Make socket connection to the server
+     *
+     * @throws Stomp_Exception
+     */
+    protected function _makeConnection ()
+    {
+        if (count($this->_hosts) == 0) {
+            require_once 'Stomp/Exception.php';
+            throw new Stomp_Exception("No broker defined");
+        }
+        
+        // force disconnect, if previous established connection exists
+        $this->disconnect();
+        
+        $i = $this->_currentHost;
+        $att = 0;
+        $connected = false;
+        while (! $connected && $att ++ < $this->_attempts) {
+            if (isset($this->_params['randomize']) && $this->_params['randomize'] == 'true') {
+                $i = rand(0, count($this->_hosts) - 1);
+            } else {
+                $i = ($i + 1) % count($this->_hosts);
+            }
+            $broker = $this->_hosts[$i];
+            $host = $broker[0];
+            $port = $broker[1];
+            $scheme = $broker[2];
+            if ($port == null) {
+                $port = $this->_defaultPort;
+            }
+            if ($this->_socket != null) {
+                fclose($this->_socket);
+                $this->_socket = null;
+            }
+            $this->_socket = @fsockopen($scheme . '://' . $host, $port);
+            if (!is_resource($this->_socket) && $att >= $this->_attempts && !array_key_exists($i + 1, $this->_hosts)) {
+                require_once 'Stomp/Exception.php';
+                throw new Stomp_Exception("Could not connect to $host:$port ($att/{$this->_attempts})");
+            } else if (is_resource($this->_socket)) {
+                $connected = true;
+                $this->_currentHost = $i;
+                break;
+            }
+        }
+        if (! $connected) {
+            require_once 'Stomp/Exception.php';
+            throw new Stomp_Exception("Could not connect to a broker");
+        }
+    }
+    /**
+     * Connect to server
+     *
+     * @param string $username
+     * @param string $password
+     * @return boolean
+     * @throws Stomp_Exception
+     */
+    public function connect ($username = '', $password = '')
+    {
+        $this->_makeConnection();
+        if ($username != '') {
+            $this->_username = $username;
+        }
+        if ($password != '') {
+            $this->_password = $password;
+        }
+		$headers = array('login' => $this->_username , 'passcode' => $this->_password);
+		if ($this->clientId != null) {
+			$headers["client-id"] = $this->clientId;
+		}
+		$frame = new Stomp_Frame("CONNECT", $headers);
+        $this->_writeFrame($frame);
+        $frame = $this->readFrame();
+        if ($frame instanceof Stomp_Frame && $frame->command == 'CONNECTED') {
+            $this->_sessionId = $frame->headers["session"];
+            return true;
+        } else {
+            require_once 'Stomp/Exception.php';
+            if ($frame instanceof Stomp_Frame) {
+                throw new Stomp_Exception("Unexpected command: {$frame->command}", 0, $frame->body);
+            } else {
+                throw new Stomp_Exception("Connection not acknowledged");
+            }
+        }
+    }
+    
+    /**
+     * Check if client session has ben established
+     *
+     * @return boolean
+     */
+    public function isConnected ()
+    {
+        return !empty($this->_sessionId) && is_resource($this->_socket);
+    }
+    /**
+     * Current stomp session ID
+     *
+     * @return string
+     */
+    public function getSessionId()
+    {
+        return $this->_sessionId;
+    }
+    /**
+     * Send a message to a destination in the messaging system 
+     *
+     * @param string $destination Destination queue
+     * @param string|Stomp_Frame $msg Message
+     * @param array $properties
+     * @param boolean $sync Perform request synchronously
+     * @return boolean
+     */
+    public function send ($destination, $msg, $properties = null, $sync = null)
+    {
+        if ($msg instanceof Stomp_Frame) {
+            $msg->headers['destination'] = $destination;
+            $msg->headers = array_merge($msg->headers, $properties);
+            $frame = $msg;
+        } else {
+            $headers = $properties;
+            $headers['destination'] = $destination;
+            $frame = new Stomp_Frame('SEND', $headers, $msg);
+        }
+        $this->_prepareReceipt($frame, $sync);
+        $this->_writeFrame($frame);
+        return $this->_waitForReceipt($frame, $sync);
+    }
+    /**
+     * Prepair frame receipt
+     *
+     * @param Stomp_Frame $frame
+     * @param boolean $sync
+     */
+    protected function _prepareReceipt (Stomp_Frame $frame, $sync)
+    {
+        $receive = $this->sync;
+        if ($sync !== null) {
+            $receive = $sync;
+        }
+        if ($receive == true) {
+            $frame->headers['receipt'] = md5(microtime());
+        }
+    }
+    /**
+     * Wait for receipt
+     *
+     * @param Stomp_Frame $frame
+     * @param boolean $sync
+     * @return boolean
+     * @throws Stomp_Exception
+     */
+    protected function _waitForReceipt (Stomp_Frame $frame, $sync)
+    {
+
+        $receive = $this->sync;
+        if ($sync !== null) {
+            $receive = $sync;
+        }
+        if ($receive == true) {
+            $id = (isset($frame->headers['receipt'])) ? $frame->headers['receipt'] : null;
+            if ($id == null) {
+                return true;
+            }
+            $frame = $this->readFrame();
+            if ($frame instanceof Stomp_Frame && $frame->command == 'RECEIPT') {
+                if ($frame->headers['receipt-id'] == $id) {
+                    return true;
+                } else {
+                    require_once 'Stomp/Exception.php';
+                    throw new Stomp_Exception("Unexpected receipt id {$frame->headers['receipt-id']}", 0, $frame->body);
+                }
+            } else {
+                require_once 'Stomp/Exception.php';
+                if ($frame instanceof Stomp_Frame) {
+                    throw new Stomp_Exception("Unexpected command {$frame->command}", 0, $frame->body);
+                } else {
+                    throw new Stomp_Exception("Receipt not received");
+                }
+            }
+        }
+        return true;
+    }
+    /**
+     * Register to listen to a given destination
+     *
+     * @param string $destination Destination queue
+     * @param array $properties
+     * @param boolean $sync Perform request synchronously
+     * @return boolean
+     * @throws Stomp_Exception
+     */
+    public function subscribe ($destination, $properties = null, $sync = null)
+    {
+        $headers = array('ack' => 'client');
+		$headers['activemq.prefetchSize'] = $this->prefetchSize;
+		if ($this->clientId != null) {
+			$headers["activemq.subcriptionName"] = $this->clientId;
+		}
+        if (isset($properties)) {
+            foreach ($properties as $name => $value) {
+                $headers[$name] = $value;
+            }
+        }
+        $headers['destination'] = $destination;
+        $frame = new Stomp_Frame('SUBSCRIBE', $headers);
+        $this->_prepareReceipt($frame, $sync);
+        $this->_writeFrame($frame);
+        if ($this->_waitForReceipt($frame, $sync) == true) {
+            $this->_subscriptions[$destination] = $properties;
+            return true;
+        } else {
+            return false;
+        }
+    }
+    /**
+     * Remove an existing subscription
+     *
+     * @param string $destination
+     * @param array $properties
+     * @param boolean $sync Perform request synchronously
+     * @return boolean
+     * @throws Stomp_Exception
+     */
+    public function unsubscribe ($destination, $properties = null, $sync = null)
+    {
+        $headers = array();
+        if (isset($properties)) {
+            foreach ($properties as $name => $value) {
+                $headers[$name] = $value;
+            }
+        }
+        $headers['destination'] = $destination;
+        $frame = new Stomp_Frame('UNSUBSCRIBE', $headers);
+        $this->_prepareReceipt($frame, $sync);
+        $this->_writeFrame($frame);
+        if ($this->_waitForReceipt($frame, $sync) == true) {
+            unset($this->_subscriptions[$destination]);
+            return true;
+        } else {
+            return false;
+        }
+    }
+    /**
+     * Start a transaction
+     *
+     * @param string $transactionId
+     * @param boolean $sync Perform request synchronously
+     * @return boolean
+     * @throws Stomp_Exception
+     */
+    public function begin ($transactionId = null, $sync = null)
+    {
+        $headers = array();
+        if (isset($transactionId)) {
+            $headers['transaction'] = $transactionId;
+        }
+        $frame = new Stomp_Frame('BEGIN', $headers);
+        $this->_prepareReceipt($frame, $sync);
+        $this->_writeFrame($frame);
+        return $this->_waitForReceipt($frame, $sync);
+    }
+    /**
+     * Commit a transaction in progress
+     *
+     * @param string $transactionId
+     * @param boolean $sync Perform request synchronously
+     * @return boolean
+     * @throws Stomp_Exception
+     */
+    public function commit ($transactionId = null, $sync = null)
+    {
+        $headers = array();
+        if (isset($transactionId)) {
+            $headers['transaction'] = $transactionId;
+        }
+        $frame = new Stomp_Frame('COMMIT', $headers);
+        $this->_prepareReceipt($frame, $sync);
+        $this->_writeFrame($frame);
+        return $this->_waitForReceipt($frame, $sync);
+    }
+    /**
+     * Roll back a transaction in progress
+     *
+     * @param string $transactionId
+     * @param boolean $sync Perform request synchronously
+     */
+    public function abort ($transactionId = null, $sync = null)
+    {
+        $headers = array();
+        if (isset($transactionId)) {
+            $headers['transaction'] = $transactionId;
+        }
+        $frame = new Stomp_Frame('ABORT', $headers);
+        $this->_prepareReceipt($frame, $sync);
+        $this->_writeFrame($frame);
+        return $this->_waitForReceipt($frame, $sync);
+    }
+    /**
+     * Acknowledge consumption of a message from a subscription
+	 * Note: This operation is always asynchronous
+     *
+     * @param string|Stomp_Frame $messageMessage ID
+     * @param string $transactionId
+     * @return boolean
+     * @throws Stomp_Exception
+     */
+    public function ack ($message, $transactionId = null)
+    {
+        if ($message instanceof Stomp_Frame) {
+            $frame = new Stomp_Frame('ACK', $message->headers);
+            $this->_writeFrame($frame);
+            return true;
+        } else {
+            $headers = array();
+            if (isset($transactionId)) {
+                $headers['transaction'] = $transactionId;
+            }
+            $headers['message-id'] = $message;
+            $frame = new Stomp_Frame('ACK', $headers);
+            $this->_writeFrame($frame);
+            return true;
+        }
+    }
+    /**
+     * Graceful disconnect from the server
+     *
+     */
+    public function disconnect ()
+    {
+		$header = array();
+
+		if ($this->clientId != null) {
+			$headers["client-id"] = $this->clientId;
+		}
+
+        if (is_resource($this->_socket)) {
+            $this->_writeFrame(new Stomp_Frame('DISCONNECT', $headers));
+            fclose($this->_socket);
+        }
+        $this->_socket = null;
+        $this->_sessionId = null;
+        $this->_currentHost = -1;
+        $this->_subscriptions = array();
+        $this->_username = '';
+        $this->_password = '';
+    }
+    /**
+     * Write frame to server
+     *
+     * @param Stomp_Frame $stompFrame
+     */
+    protected function _writeFrame (Stomp_Frame $stompFrame)
+    {
+        if (!is_resource($this->_socket)) {
+            require_once 'Stomp/Exception.php';
+            throw new Stomp_Exception('Socket connection hasn\'t been established');
+        }
+
+        $data = $stompFrame->__toString();
+        $r = fwrite($this->_socket, $data, strlen($data));
+        if ($r === false || $r == 0) {
+            $this->_reconnect();
+            $this->_writeFrame($stompFrame);
+        }
+    }
+    
+    /**
+     * Set timeout to wait for content to read
+     *
+     * @param int $seconds_to_wait  Seconds to wait for a frame
+     * @param int $milliseconds Milliseconds to wait for a frame
+     */
+    public function setReadTimeout($seconds, $milliseconds = 0) 
+    {
+        $this->_read_timeout_seconds = $seconds;
+        $this->_read_timeout_milliseconds = $milliseconds;
+    }
+    
+    /**
+     * Read responce frame from server
+     *
+     * @return Stomp_Frame|Stomp_Message_Map|boolean False when no frame to read
+     */
+    public function readFrame ()
+    {
+        if (!$this->hasFrameToRead()) {
+            return false;
+        }
+        
+        $rb = 1024;
+        $data = '';
+        do {
+            $read = fgets($this->_socket, $rb);
+            if ($read === false) {
+                $this->_reconnect();
+                return $this->readFrame();
+            }
+            $data .= $read;
+            $len = strlen($data);
+        } while (($len < 2 || ! ($data[$len - 2] == "\x00" && $data[$len - 1] == "\n")));
+        
+        list ($header, $body) = explode("\n\n", $data, 2);
+        $header = explode("\n", $header);
+        $headers = array();
+        $command = null;
+        foreach ($header as $v) {
+            if (isset($command)) {
+                list ($name, $value) = explode(':', $v, 2);
+                $headers[$name] = $value;
+            } else {
+                $command = $v;
+            }
+        }
+        $frame = new Stomp_Frame($command, $headers, trim($body));
+        if (isset($frame->headers['amq-msg-type']) && $frame->headers['amq-msg-type'] == 'MapMessage') {
+            require_once 'Stomp/Message/Map.php';
+            return new Stomp_Message_Map($frame);
+        } else {
+            return $frame;
+        }
+    }
+    
+    /**
+     * Check if there is a frame to read
+     *
+     * @return boolean
+     */
+    public function hasFrameToRead()
+    {
+        $read = array($this->_socket);
+        $write = null;
+        $except = null;
+        
+        $has_frame_to_read = stream_select($read, $write, $except, $this->_read_timeout_seconds, $this->_read_timeout_milliseconds);
+
+        if ($has_frame_to_read === false) {
+            throw new Stomp_Exception('Check failed to determin if the socket is readable');
+        } else if ($has_frame_to_read > 0) {
+            return true;
+        } else {
+            return false; 
+        }
+    }
+    
+    /**
+     * Reconnects and renews subscriptions (if there were any)
+     * Call this method when you detect connection problems     
+     */
+    protected function _reconnect ()
+    {
+        $subscriptions = $this->_subscriptions;
+        
+        $this->connect($this->_username, $this->_password);
+        foreach ($subscriptions as $dest => $properties) {
+            $this->subscribe($dest, $properties);
+        }
+    }
+    /**
+     * Graceful object desruction
+     *
+     */
+    public function __destruct()
+    {
+        $this->disconnect();
+    }
+}
+?>
diff --git a/extlib/Stomp/Exception.php b/extlib/Stomp/Exception.php
new file mode 100644
index 000000000..e6870bc15
--- /dev/null
+++ b/extlib/Stomp/Exception.php
@@ -0,0 +1,57 @@
+<?php
+/**
+ *
+ * Copyright 2005-2006 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* vim: set expandtab tabstop=3 shiftwidth=3: */
+
+/**
+ * A Stomp Connection
+ *
+ *
+ * @package Stomp
+ * @author Michael Caplan <mcaplan@labnet.net>
+ * @version $Revision: 23 $
+ */

+class Stomp_Exception extends Exception

+{
+    protected $_details;
+    
+    /**
+     * Constructor
+     *
+     * @param string $message Error message
+     * @param int $code Error code
+     * @param string $details Stomp server error details
+     */
+    public function __construct($message = null, $code = 0, $details = '')
+    {
+        $this->_details = $details;
+        
+        parent::__construct($message, $code);
+    }
+    
+    /**
+     * Stomp server error details
+     *
+     * @return string
+     */
+    public function getDetails()
+    {
+        return $this->_details;
+    }
+}

+?>
\ No newline at end of file
diff --git a/extlib/Stomp/Frame.php b/extlib/Stomp/Frame.php
new file mode 100644
index 000000000..dc59c1cb7
--- /dev/null
+++ b/extlib/Stomp/Frame.php
@@ -0,0 +1,80 @@
+<?php
+/**
+ *
+ * Copyright 2005-2006 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* vim: set expandtab tabstop=3 shiftwidth=3: */
+

+/**

+ * Stomp Frames are messages that are sent and received on a StompConnection.

+ *

+ * @package Stomp

+ * @author Hiram Chirino <hiram@hiramchirino.com>

+ * @author Dejan Bosanac <dejan@nighttale.net>

+ * @author Michael Caplan <mcaplan@labnet.net>

+ * @version $Revision: 36 $

+ */

+class Stomp_Frame

+{

+    public $command;

+    public $headers = array();

+    public $body;

+    

+    /**

+     * Constructor

+     *

+     * @param string $command

+     * @param array $headers

+     * @param string $body

+     */

+    public function __construct ($command = null, $headers = null, $body = null)

+    {

+        $this->_init($command, $headers, $body);

+    }

+    

+    protected function _init ($command = null, $headers = null, $body = null)

+    {

+        $this->command = $command;

+        if ($headers != null) {

+            $this->headers = $headers;

+        }

+        $this->body = $body;

+        

+        if ($this->command == 'ERROR') {

+            require_once 'Stomp/Exception.php';

+            throw new Stomp_Exception($this->headers['message'], 0, $this->body);

+        }

+    }
+    
+    /**
+     * Convert frame to transportable string
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        $data = $this->command . "\n";
+        
+        foreach ($this->headers as $name => $value) {
+            $data .= $name . ": " . $value . "\n";
+        }
+        
+        $data .= "\n";
+        $data .= $this->body;
+        return $data .= "\x00\n";
+    }

+}

+?>
\ No newline at end of file
diff --git a/extlib/Stomp/Message.php b/extlib/Stomp/Message.php
new file mode 100644
index 000000000..6bcad3efd
--- /dev/null
+++ b/extlib/Stomp/Message.php
@@ -0,0 +1,37 @@
+<?php
+/**
+ *
+ * Copyright 2005-2006 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* vim: set expandtab tabstop=3 shiftwidth=3: */
+
+require_once 'Stomp/Frame.php';
+
+/**
+ * Basic text stomp message
+ *
+ * @package Stomp
+ * @author Dejan Bosanac <dejan@nighttale.net>
+ * @version $Revision: 23 $
+ */
+class Stomp_Message extends Stomp_Frame
+{
+    public function __construct ($body, $headers = null)
+    {
+        $this->_init("SEND", $headers, $body);
+    }
+}
+?>
\ No newline at end of file
diff --git a/extlib/Stomp/Message/Bytes.php b/extlib/Stomp/Message/Bytes.php
new file mode 100644
index 000000000..c75f23e43
--- /dev/null
+++ b/extlib/Stomp/Message/Bytes.php
@@ -0,0 +1,47 @@
+<?php
+/**
+ *
+ * Copyright 2005-2006 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* vim: set expandtab tabstop=3 shiftwidth=3: */
+
+require_once 'Stomp/Message.php';
+
+/**
+ * Message that contains a stream of uninterpreted bytes
+ *
+ * @package Stomp
+ * @author Dejan Bosanac <dejan@nighttale.net>
+ * @version $Revision: 23 $
+ */
+class Stomp_Message_Bytes extends Stomp_Message
+{
+    /**
+     * Constructor
+     *
+     * @param string $body
+     * @param array $headers
+     */
+    function __construct ($body, $headers = null)
+    {
+        $this->_init("SEND", $headers, $body);
+        if ($this->headers == null) {
+            $this->headers = array();
+        }
+        $this->headers['content-length'] = count($body);
+    }
+}
+?>
\ No newline at end of file
diff --git a/extlib/Stomp/Message/Map.php b/extlib/Stomp/Message/Map.php
new file mode 100644
index 000000000..288456a84
--- /dev/null
+++ b/extlib/Stomp/Message/Map.php
@@ -0,0 +1,55 @@
+<?php
+/**
+ *
+ * Copyright 2005-2006 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* vim: set expandtab tabstop=3 shiftwidth=3: */
+
+require_once 'Stomp/Message.php';
+
+/**
+ * Message that contains a set of name-value pairs
+ *
+ * @package Stomp
+ * @author Dejan Bosanac <dejan@nighttale.net>
+ * @version $Revision: 23 $
+ */
+class Stomp_Message_Map extends Stomp_Message
+{
+    public $map;
+    
+    /**
+     * Constructor
+     *
+     * @param Stomp_Frame|string $msg
+     * @param array $headers
+     */
+    function __construct ($msg, $headers = null)
+    {
+        if ($msg instanceof Stomp_Frame) {
+            $this->_init($msg->command, $msg->headers, $msg->body);
+            $this->map = json_decode($msg->body);
+        } else {
+            $this->_init("SEND", $headers, $msg);
+            if ($this->headers == null) {
+                $this->headers = array();
+            }
+            $this->headers['amq-msg-type'] = 'MapMessage';
+            $this->body = json_encode($msg);
+        }
+    }
+}
+?>
\ No newline at end of file
diff --git a/lib/queuehandler.php b/lib/queuehandler.php
index 9ce9e32b3..752bbc6d2 100644
--- a/lib/queuehandler.php
+++ b/lib/queuehandler.php
@@ -75,15 +75,9 @@ class QueueHandler extends Daemon
         return true;
     }
     
-    function run()
-    {
-        if (!$this->start()) {
-            return false;
-        }
-        $this->log(LOG_INFO, 'checking for queued notices');
-        $transport = $this->transport();
+    function db_dispatch() {
         do {
-            $qi = Queue_item::top($transport);
+            $qi = Queue_item::top($this->transport());
             if ($qi) {
                 $this->log(LOG_INFO, 'Got item enqueued '.common_exact_date($qi->created));
                 $notice = Notice::staticGet($qi->notice_id);
@@ -115,6 +109,68 @@ class QueueHandler extends Daemon
                 $this->idle(5);
             }    
         } while (true);
+    }
+
+    function stomp_dispatch() {
+	require("Stomp.php");
+	$con = new Stomp(common_config('queue','stomp_server'));
+	if (!$con->connect()) {
+		$this->log(LOG_ERR, 'Failed to connect to queue server');
+		return false;
+	}
+	$queue_basename = common_config('queue','queue_basename');
+	// subscribe to the relevant queue (format: basename-transport)
+	$con->subscribe('/queue/'.$queue_basename.'-'.$this->transport());
+
+        do {
+            $frame = $con->readFrame();
+            if ($frame) {
+                $this->log(LOG_INFO, 'Got item enqueued '.common_exact_date($frame->headers['created']));
+
+		// XXX: Now the queue handler receives only the ID of the
+		// notice, and it has to get it from the DB
+		// A massive improvement would be avoid DB query by transmitting
+		// all the notice details via queue server...
+                $notice = Notice::staticGet($frame->body);
+
+                if ($notice) {
+                    $this->log(LOG_INFO, 'broadcasting notice ID = ' . $notice->id);
+                    $result = $this->handle_notice($notice);
+                    if ($result) {
+			// if the msg has been handled positively, ack it
+			// and the queue server will remove it from the queue
+			$con->ack($frame);
+                    	$this->log(LOG_INFO, 'finished broadcasting notice ID = ' . $notice->id);
+		    }
+		    else {
+			// no ack
+                        $this->log(LOG_WARNING, 'Failed broadcast for notice ID = ' . $notice->id);
+                    }
+                    $notice->free();
+                    unset($notice);
+                    $notice = null;
+                } else {
+                    $this->log(LOG_WARNING, 'queue item for notice that does not exist');
+                }
+	    }
+        } while (true);
+	
+	$con->disconnect();
+    }
+	
+
+    function run()
+    {
+        if (!$this->start()) {
+            return false;
+        }
+        $this->log(LOG_INFO, 'checking for queued notices');
+	if (common_config('queue','subsystem') == 'stomp') {
+		$this->stomp_dispatch();
+	}
+	else {
+		$this->db_dispatch();
+	}
         if (!$this->finish()) {
             return false;
         }
@@ -143,4 +199,4 @@ class QueueHandler extends Daemon
         common_log($level, $this->class_name() . ' ('. $this->get_id() .'): '.$msg);
     }
 }
-    
\ No newline at end of file
+    
diff --git a/lib/util.php b/lib/util.php
index c5a092f63..8ef19f579 100644
--- a/lib/util.php
+++ b/lib/util.php
@@ -1138,18 +1138,44 @@ function common_twitter_broadcast($notice, $flink)
 
 function common_enqueue_notice($notice)
 {
-    foreach (array('jabber', 'omb', 'sms', 'public') as $transport) {
-        $qi = new Queue_item();
-        $qi->notice_id = $notice->id;
-        $qi->transport = $transport;
-        $qi->created = $notice->created;
-        $result = $qi->insert();
-        if (!$result) {
-            $last_error = &PEAR::getStaticProperty('DB_DataObject','lastError');
-            common_log(LOG_ERR, 'DB error inserting queue item: ' . $last_error->message);
-            return false;
+    if (common_config('queue','subsystem') == 'stomp') {
+	// use an external message queue system via STOMP
+	require_once("Stomp.php");
+	$con = new Stomp(common_config('queue','stomp_server'));
+	if (!$con->connect()) {
+		common_log(LOG_ERR, 'Failed to connect to queue server');
+		return false;
+	}
+	$queue_basename = common_config('queue','queue_basename');
+    	foreach (array('jabber', 'omb', 'sms', 'public') as $transport) {
+		if (!$con->send(
+			'/queue/'.$queue_basename.'-'.$transport, // QUEUE
+			$notice->id, 		// BODY of the message
+			array (			// HEADERS of the msg
+			'created' => $notice->created
+			))) {
+			common_log(LOG_ERR, 'Error sending to '.$transport.' queue');
+			return false;
+		}
+        common_log(LOG_DEBUG, 'complete remote queueing notice ID = ' . $notice->id . ' for ' . $transport);
+	}
+	$result = true;
+    }
+    else {
+	// in any other case, 'internal'
+    	foreach (array('jabber', 'omb', 'sms', 'public') as $transport) {
+	        $qi = new Queue_item();
+        	$qi->notice_id = $notice->id;
+	        $qi->transport = $transport;
+        	$qi->created = $notice->created;
+	        $result = $qi->insert();
+        	if (!$result) {
+	            $last_error = &PEAR::getStaticProperty('DB_DataObject','lastError');
+        	    common_log(LOG_ERR, 'DB error inserting queue item: ' . $last_error->message);
+            	    return false;
+        	}
+        	common_log(LOG_DEBUG, 'complete queueing notice ID = ' . $notice->id . ' for ' . $transport);
         }
-        common_log(LOG_DEBUG, 'complete queueing notice ID = ' . $notice->id . ' for ' . $transport);
     }
     return $result;
 }