Huge update.

src/UglyQueue.php

@@ -5,159 +5,89 @@ use DCarbone\Helpers\FileHelper;
 /**
  * Class UglyQueue
  * @package DCarbone
+ *
+ * @property string name
+ * @property string path
+ * @property bool locked
  */
-class UglyQueue
+class UglyQueue implements \Serializable, \SplSubject
 {
+    const NOTIFY_QUEUE_INITIALIZED              = 0;
+    const NOTIFY_QUEUE_LOCKED                   = 1;
+    const NOTIFY_QUEUE_FAILED_TO_LOCK           = 2;
+    const NOTIFY_QUEUE_LOCKED_BY_OTHER_PROCESS  = 3;
+    const NOTIFY_QUEUE_UNLOCKED                 = 4;
+    const NOTIFY_QUEUE_PROCESSING               = 5;
+    const NOTIFY_QUEUE_REACHED_END              = 6;
+
+    /** @var int */
+    public $notifyStatus;
+
+    const QUEUE_READONLY = 0;
+    const QUEUE_READWRITE = 1;
+
     /** @var array */
-    protected $config;
+    private $observers = array();
+
+    /** @var int */
+    protected $mode = null;
 
     /** @var string */
-    protected $queueBaseDir;
+    protected $_name;
 
     /** @var string */
-    protected $queueGroup = null;
+    protected $_path;
-
-    /** @var string */
-    protected $queueGroupDirPath = null;
 
     /** @var bool */
-    protected $haveLock = false;
+    protected $_locked = false;
-
-    /** @var bool */
-    protected $init = false;
 
     /** @var resource */
     protected $_tmpHandle;
 
     /**
-     * @param array $config
+     * @param string $directoryPath
+     * @param array $observers
      * @throws \RuntimeException
      * @throws \InvalidArgumentException
+     * @return UglyQueue
      */
-    public function __construct(array $config)
+    public static function queueWithGroupDirectoryPathAndObservers($directoryPath, array $observers = array())
     {
-        if (!isset($config['queue-base-dir']))
+        if (!is_string($directoryPath))
-            throw new \InvalidArgumentException('UglyQueue::__construct - "$config" parameter "queue-base-dir" not seen.');
+            throw new \InvalidArgumentException('Argument 1 expected to be string, '.gettype($directoryPath).' seen');
 
-        if (!is_dir($config['queue-base-dir']) || !is_writable($config['queue-base-dir']))
+        if (($directoryPath = trim($directoryPath)) === '')
-            throw new \RuntimeException('UglyQueue::__construct - "$config[\'queue-base-dir\']" points to a directory that either doesn\'t exist or is not writable');
+            throw new \InvalidArgumentException('Empty string passed for argument 1');
 
-        $this->config = $config;
+        if (file_exists($directoryPath))
-
+        {
-        $this->queueBaseDir = $this->config['queue-base-dir'];
+            if (!is_dir($directoryPath))
+                throw new \RuntimeException('Argument 1 expected to be path to directory, path to non-directory seen');
+        }
+        else if (!@mkdir($directoryPath))
+        {
+            throw new \RuntimeException('Unable to create queue directory at path: "'.$directoryPath.'".');
         }
 
-    /**
+        $uglyQueue = new UglyQueue();
-     * Destructor
+        $uglyQueue->observers = $observers;
-     */
-    public function __destruct()
-    {
-        $this->unlock();
-        $this->_populateQueue();
-    }
 
-    /**
+        $split = preg_split('#[/\\]+/#', $directoryPath);
-     * @param int $ttl Time to live in seconds
-     * @throws \InvalidArgumentException
-     * @return bool
-     */
-    public function lock($ttl = 250)
-    {
-        if (!is_int($ttl))
-            throw new \InvalidArgumentException('UglyQueue::lock - Argument 1 expected to be positive integer, "'.gettype($ttl).'" seen');
 
-        if ($ttl < 0)
+        $uglyQueue->_name = end($split);
-            throw new \InvalidArgumentException('UglyQueue::lock - Argument 1 expected to be positive integer, "'.$ttl.'" seen');
+        $uglyQueue->_path = rtrim(realpath(implode(DIRECTORY_SEPARATOR, $split)), "/\\").DIRECTORY_SEPARATOR;
 
-        $already_locked = $this->isLocked();
+        if (is_writable($uglyQueue->_path))
-
+            $uglyQueue->mode = self::QUEUE_READWRITE;
-        // If there is no lock, currently
+        else if (is_readable($uglyQueue->_path))
-        if ($already_locked === false)
+            $uglyQueue->mode = self::QUEUE_READONLY;
-            return $this->haveLock = $this->createQueueLock($ttl);
-
-        // If we make it this far, there is already a lock in place.
-        return $this->haveLock = false;
-    }
-
-    /**
-     * @param int $ttl seconds to live
-     * @return bool
-     */
-    protected function createQueueLock($ttl)
-    {
-        $ok = (bool)@file_put_contents(
-            $this->queueGroupDirPath.'queue.lock',
-            json_encode(array('ttl' => $ttl, 'born' => time())));
-
-        if ($ok !== true)
-            return false;
-
-        $this->haveLock = true;
-        return true;
-    }
-
-    /**
-     * Close this ugly queue, writing out contents to file.
-     */
-    public function unlock()
-    {
-        if ($this->haveLock === true)
-        {
-            unlink($this->queueGroupDirPath.'queue.lock');
-            $this->haveLock = false;
-        }
-    }
-
-    /**
-     * @throws \RuntimeException
-     * @return bool
-     */
-    public function isLocked()
-    {
-        if ($this->init === false)
-            throw new \RuntimeException('UglyQueue::isLocked - Must first initialize queue');
-
-        // First check for lock file
-        if (is_file($this->queueGroupDirPath.'queue.lock'))
-        {
-            $lock = json_decode(file_get_contents($this->queueGroupDirPath.'queue.lock'), true);
-
-            // If we have an invalid lock structure, THIS IS BAD.
-            if (!isset($lock['ttl']) || !isset($lock['born']))
-                throw new \RuntimeException('UglyQueue::isLocked - Invalid "queue.lock" file structure seen at "'.$this->queueGroupDirPath.'queue.lock'.'"');
-
-            // Otherwise...
-            $lock_ttl = ((int)$lock['born'] + (int)$lock['ttl']);
-
-            // If we're within the TTL of the lock, assume another thread is already processing.
-            // We'll pick it up on the next go around.
-            if ($lock_ttl > time())
-                return true;
-
-            // Else, remove lock file and assume we're good to go!
-            unlink($this->queueGroupDirPath.'queue.lock');
-            return false;
-        }
-
-        // If no file, assume not locked.
-        return false;
-    }
-
-    /**
-     * @param string $queueGroup
-     */
-    public function initialize($queueGroup)
-    {
-        $this->queueGroup = $queueGroup;
-        $this->queueGroupDirPath = $this->queueBaseDir.$queueGroup.DIRECTORY_SEPARATOR;
-
-        // Create directory for this queue group
-        if (!is_dir($this->queueGroupDirPath))
-            mkdir($this->queueGroupDirPath);
 
         // Insert "don't look here" index.html file
-        if (!file_exists($this->queueGroupDirPath.'index.html'))
+        if (!file_exists($uglyQueue->_path.'index.html'))
         {
+            if ($uglyQueue->mode === self::QUEUE_READONLY)
+                throw new \RuntimeException('Cannot initialize queue with name "'.$uglyQueue->_name.'", the user lacks permission to create files.');
+
             $html = <<<HTML
 <html>
 <head>
@@ -168,13 +98,153 @@ class UglyQueue
 </body>
 </html>
 HTML;
-            file_put_contents($this->queueGroupDirPath.'index.html', $html);
+            file_put_contents($uglyQueue->_path.'index.html', $html);
         }
 
-        if (!file_exists($this->queueGroupDirPath.'queue.txt'))
+        if (!file_exists($uglyQueue->_path.'queue.txt'))
-            file_put_contents($this->queueGroupDirPath.'queue.txt', '');
+        {
+            if ($uglyQueue->mode === self::QUEUE_READONLY)
+                throw new \RuntimeException('Cannot initialize queue with name "'.$uglyQueue->_name.'", the user lacks permission to create files.');
 
-        $this->init = true;
+            file_put_contents($uglyQueue->_path.'queue.txt', '');
+        }
+
+        $uglyQueue->notifyStatus = self::NOTIFY_QUEUE_INITIALIZED;
+        $uglyQueue->notify();
+
+        return $uglyQueue;
+    }
+
+    /**
+     * @param string $param
+     * @return string
+     * @throws \OutOfBoundsException
+     */
+    public function __get($param)
+    {
+        switch($param)
+        {
+            case 'name' :
+                return $this->_name;
+
+            case 'path':
+                return $this->_path;
+
+            case 'locked':
+                return $this->_locked;
+
+            default:
+                throw new \OutOfBoundsException(get_class($this).' does not have a property named "'.$param.'".');
+        }
+    }
+
+    /**
+     * Destructor
+     */
+    public function __destruct()
+    {
+        $this->_populateQueue();
+        $this->unlock();
+        file_put_contents($this->_path.UglyQueueManager::UGLY_QUEUE_SERIALIZED_NAME, serialize($this));
+    }
+
+    /**
+     * @param int $ttl Time to live in seconds
+     * @throws \InvalidArgumentException
+     * @return bool
+     */
+    public function lock($ttl = 250)
+    {
+        if (!is_int($ttl))
+            throw new \InvalidArgumentException('Argument 1 expected to be integer, "'.gettype($ttl).'" seen');
+
+        if ($ttl < 0)
+            throw new \InvalidArgumentException('Argument 1 expected to be positive integer, "'.$ttl.'" seen');
+
+        $alreadyLocked = $this->isLocked();
+
+        // If there is currently no lock
+        if ($alreadyLocked === false)
+            return $this->createLockFile($ttl);
+
+        // If we make it this far, there is already a lock in place.
+        $this->_locked = false;
+        $this->notifyStatus = self::NOTIFY_QUEUE_LOCKED_BY_OTHER_PROCESS;
+        $this->notify();
+
+        return false;
+    }
+
+    /**
+     * @param int $ttl seconds to live
+     * @return bool
+     */
+    protected function createLockFile($ttl)
+    {
+        $ok = (bool)@file_put_contents(
+            $this->_path.'queue.lock',
+            json_encode(array('ttl' => $ttl, 'born' => time())));
+
+        if ($ok !== true)
+        {
+            $this->notifyStatus = self::NOTIFY_QUEUE_FAILED_TO_LOCK;
+            $this->notify();
+            return $this->_locked = false;
+        }
+
+        $this->_locked = true;
+
+        $this->notifyStatus = self::NOTIFY_QUEUE_LOCKED;
+        $this->notify();
+
+        return true;
+    }
+
+    /**
+     * Close this ugly queue, writing out contents to file.
+     */
+    public function unlock()
+    {
+        if ($this->_locked === true)
+        {
+            unlink($this->_path.'queue.lock');
+            $this->_locked = false;
+
+            $this->notifyStatus = self::NOTIFY_QUEUE_UNLOCKED;
+            $this->notify();
+        }
+    }
+
+    /**
+     * @throws \RuntimeException
+     * @return bool
+     */
+    public function isLocked()
+    {
+        // First check for lock file
+        if (is_file($this->_path.'queue.lock'))
+        {
+            $lock = json_decode(file_get_contents($this->_path.'queue.lock'), true);
+
+            // If we have an invalid lock structure, THIS IS BAD.
+            if (!isset($lock['ttl']) || !isset($lock['born']))
+                throw new \RuntimeException(get_class($this).'::isLocked - Invalid "queue.lock" file structure seen at "'.$this->_path.'queue.lock'.'"');
+
+            // Otherwise...
+            $lock_ttl = ((int)$lock['born'] + (int)$lock['ttl']);
+
+            // If we're within the TTL of the lock, assume another thread is already processing.
+            // We'll pick it up on the next go around.
+            if ($lock_ttl > time())
+                return true;
+
+            // Else, remove lock file and assume we're good to go!
+            unlink($this->_path.'queue.lock');
+            return false;
+        }
+
+        // If no file, assume not locked.
+        return false;
     }
 
     /**
@@ -185,30 +255,37 @@ HTML;
      */
     public function processQueue($count = 1)
     {
-        if ($this->init === false)
+        if ($this->mode === self::QUEUE_READONLY)
-            throw new \RuntimeException('UglyQueue::processQueue - Must first initialize queue!');
+            throw new \RuntimeException('Queue "'.$this->_name.'" cannot be processed.'.
+            '  It was started in Read-Only mode (the user running this process does not have permission to write to the queue directory).');
 
         // If we don't have a lock, assume issue and move on.
-        if ($this->haveLock === false)
+        if ($this->_locked === false)
-            throw new \RuntimeException('UglyQueue::processQueue - Cannot process queue locked by another process');
+            throw new \RuntimeException('Cannot process queue named "'.$this->_name.'".  It is locked by another process.');
 
         // If non-int valid is passed
         if (!is_int($count))
-            throw new \InvalidArgumentException('UglyQueue::processQueue - Argument 1 expected to be integer greater than 0, "'.gettype($count).'" seen');
+            throw new \InvalidArgumentException('Argument 1 expected to be integer greater than 0, "'.gettype($count).'" seen');
 
         // If negative integer passed
         if ($count <= 0)
-            throw new \InvalidArgumentException('UglyQueue::processQueue - Argument 1 expected to be integer greater than 0, "'.$count.'" seen');
+            throw new \InvalidArgumentException('Argument 1 expected to be integer greater than 0, "'.$count.'" seen');
+
+        if ($this->notifyStatus !== self::NOTIFY_QUEUE_PROCESSING)
+        {
+            $this->notifyStatus = self::NOTIFY_QUEUE_PROCESSING;
+            $this->notify();
+        }
 
         // Find number of lines in the queue file
-        $lineCount  = FileHelper::getLineCount($this->queueGroupDirPath.'queue.txt');
+        $lineCount  = FileHelper::getLineCount($this->_path.'queue.txt');
 
         // If queue line count is 0, assume empty
         if ($lineCount === 0)
             return false;
 
         // Try to open the file for reading / writing.
-        $queueFileHandle = fopen($this->queueGroupDirPath.'queue.txt', 'r+');
+        $queueFileHandle = fopen($this->_path.'queue.txt', 'r+');
         if ($queueFileHandle === false)
             $this->unlock();
 
@@ -231,11 +308,14 @@ HTML;
             rewind($queueFileHandle);
             ftruncate($queueFileHandle, 0);
             fclose($queueFileHandle);
+
+            $this->notifyStatus = self::NOTIFY_QUEUE_REACHED_END;
+            $this->notify();
         }
         // Otherwise, create new queue file minus the processed lines.
         else
         {
-            $tmp = fopen($this->queueGroupDirPath.'queue.tmp', 'w+');
+            $tmp = fopen($this->_path.'queue.tmp', 'w+');
             rewind($queueFileHandle);
             $i = 0;
             while (($line = fgets($queueFileHandle)) !== false && $i < $start_line)
@@ -248,8 +328,8 @@ HTML;
 
             fclose($queueFileHandle);
             fclose($tmp);
-            unlink($this->queueGroupDirPath.'queue.txt');
+            unlink($this->_path.'queue.txt');
-            rename($this->queueGroupDirPath.'queue.tmp', $this->queueGroupDirPath.'queue.txt');
+            rename($this->_path.'queue.tmp', $this->_path.'queue.txt');
         }
 
         return $data;
@@ -263,18 +343,18 @@ HTML;
      */
     public function addToQueue($key, $value)
     {
-        if ($this->init === false)
+        if ($this->mode === self::QUEUE_READONLY)
-            throw new \RuntimeException('UglyQueue::addToQueue - Must first initialize queue!');
+            throw new \RuntimeException('Cannot add items to queue "'.$this->_name.'" as it is in read-only mode');
 
         // If we don't have a lock, assume issue and move on.
-        if ($this->haveLock === false)
+        if ($this->_locked === false)
-            throw new \RuntimeException('UglyQueue::addToQueue - You do not have a lock on this queue');
+            throw new \RuntimeException('Cannot add items to queue "'.$this->_name.'". Queue is already locked by another process');
 
         if (!is_resource($this->_tmpHandle))
         {
-            $this->_tmpHandle = fopen($this->queueGroupDirPath.'queue.tmp', 'w+');
+            $this->_tmpHandle = fopen($this->_path.'queue.tmp', 'w+');
             if ($this->_tmpHandle === false)
-                throw new \RuntimeException('UglyQueue::addToQueue - Unable to create "queue.tmp" file');
+                throw new \RuntimeException('Unable to create "queue.tmp" file.');
         }
 
         if (is_array($value) || $value instanceof \stdClass)
@@ -295,9 +375,9 @@ HTML;
     {
         if (is_resource($this->_tmpHandle))
         {
-            if (file_exists($this->queueGroupDirPath.'queue.txt'))
+            if (file_exists($this->_path.'queue.txt'))
             {
-                $queueFileHandle = fopen($this->queueGroupDirPath.'queue.txt', 'r+');
+                $queueFileHandle = fopen($this->_path.'queue.txt', 'r+');
                 while (($line = fgets($queueFileHandle)) !== false)
                 {
                     if ($line !== "\n" && $line !== "")
@@ -305,11 +385,11 @@ HTML;
                 }
 
                 fclose($queueFileHandle);
-                unlink($this->queueGroupDirPath.'queue.txt');
+                unlink($this->_path.'queue.txt');
             }
 
             fclose($this->_tmpHandle);
-            rename($this->queueGroupDirPath.'queue.tmp', $this->queueGroupDirPath.'queue.txt');
+            rename($this->_path.'queue.tmp', $this->_path.'queue.txt');
         }
     }
 
@@ -319,10 +399,7 @@ HTML;
      */
     public function getQueueItemCount()
     {
-        if ($this->init === false)
+        return FileHelper::getLineCount($this->_path.'queue.txt');
-            throw new \RuntimeException('UglyQueue::getQueueItemCount - Must first initialize queue');
-
-        return FileHelper::getLineCount($this->queueGroupDirPath.'queue.txt');
     }
 
     /**
@@ -332,19 +409,16 @@ HTML;
      */
     public function keyExistsInQueue($key)
     {
-        if ($this->init === false)
-            throw new \RuntimeException('UglyQueue::keyExistsInQueue - Must first initialize queue');
-
         $key = (string)$key;
 
         // Try to open the file for reading / writing.
-        $queueFileHandle = fopen($this->queueGroupDirPath.'queue.txt', 'r');
+        $queueFileHandle = fopen($this->_path.'queue.txt', 'r');
 
         while(($line = fscanf($queueFileHandle, "%s\t")) !== false)
         {
-            list($queueKey) = $line;
+            list ($lineKey, $lineValue) = $line;
 
-            if ($key === $queueKey)
+            if ($key === $lineKey)
             {
                 fclose($queueFileHandle);
                 return true;
@@ -356,59 +430,74 @@ HTML;
     }
 
     /**
-     * @param string $groupName
+     * (PHP 5 >= 5.1.0)
-     * @return bool
+     * String representation of object
+     * @link http://php.net/manual/en/serializable.serialize.php
+     *
+     * @return string the string representation of the object or null
      */
-    public function queueExists($groupName)
+    public function serialize()
     {
-        return (bool)is_dir($this->queueBaseDir.$groupName);
+        return serialize(array($this->_name, $this->_path));
     }
 
     /**
-     * @return array
+     * (PHP 5 >= 5.1.0)
+     * Constructs the object
+     * @link http://php.net/manual/en/serializable.unserialize.php
+     *
+     * @param string $serialized The string representation of the object.
+     * @return void
      */
-    public function getInitializedQueueList()
+    public function unserialize($serialized)
     {
-        $queueList = array();
+        /** @var \DCarbone\UglyQueue $uglyQueue */
-        foreach(glob(realpath($this->queueBaseDir).DIRECTORY_SEPARATOR.'*', GLOB_ONLYDIR) as $queueDir)
+        $data = unserialize($serialized);
-        {
+        $this->_name = $data[0];
-            $exp = explode(DIRECTORY_SEPARATOR, $queueDir);
+        $this->_path = $data[1];
-            $dir = end($exp);
-            if (strpos($dir, '.') !== 0)
-                $queueList[] = $dir;
-        }
-        return $queueList;
     }
 
     /**
-     * @return boolean
+     * (PHP 5 >= 5.1.0)
+     * Attach an SplObserver
+     * @link http://php.net/manual/en/splsubject.attach.php
+     *
+     * @param \SplObserver $observer The SplObserver to attach.
+     * @return void
      */
-    public function getInit()
+    public function attach(\SplObserver $observer)
     {
-        return $this->init;
+        if (!in_array($observer, $this->observers))
+            $this->observers[] = $observer;
     }
 
     /**
-     * @return string
+     * (PHP 5 >= 5.1.0)
+     * Detach an observer
+     * @link http://php.net/manual/en/splsubject.detach.php
+     *
+     * @param \SplObserver $observer The SplObserver to detach.
+     * @return void
      */
-    public function getQueueBaseDir()
+    public function detach(\SplObserver $observer)
     {
-        return $this->queueBaseDir;
+        $idx = array_search($observer, $this->observers, true);
+        if ($idx !== false)
+            unset($this->observers[$idx]);
     }
 
     /**
-     * @return string
+     * (PHP 5 >= 5.1.0)
+     * Notify an observer
+     * @link http://php.net/manual/en/splsubject.notify.php
+     *
+     * @return void
      */
-    public function getQueueGroupDirPath()
+    public function notify()
     {
-        return $this->queueGroupDirPath;
+        for ($i = 0, $count = count($this->observers); $i < $count; $i++)
+        {
+            $this->observers[$i]->notify($this);
         }
-
-    /**
-     * @return string
-     */
-    public function getQueueGroup()
-    {
-        return $this->queueGroup;
     }
 }

src/UglyQueueManager.php

@@ -0,0 +1,234 @@
+<?php namespace DCarbone;
+
+/**
+ * Class UglyQueueManager
+ * @package DCarbone
+ */
+class UglyQueueManager implements \SplObserver, \SplSubject
+{
+    const NOTIFY_MANAGER_INITIALIZED = 0;
+    const NOTIFY_QUEUE_ADDED = 1;
+    const NOTIFY_QUEUE_REMOVED = 2;
+
+    /** @var int */
+    public $notifyStatus;
+
+    const UGLY_QUEUE_SERIALIZED_NAME = 'ugly-queue.obj';
+
+    /** @var array */
+    private $observers = array();
+
+    /** @var array */
+    protected $queues = array();
+
+    /** @var array */
+    protected $config = array();
+
+    /** @var string */
+    protected $queueBaseDir;
+
+    /**
+     * Constructor
+     *
+     * @param array $config
+     * @param array $observers
+     * @throws \RuntimeException
+     * @throws \InvalidArgumentException
+     */
+    protected function __construct(array $config, array $observers = array())
+    {
+        if (!isset($config['queue-base-dir']))
+            throw new \InvalidArgumentException('"$config" parameter "queue-base-dir" not seen.');
+
+        if (!is_dir($config['queue-base-dir']))
+            throw new \RuntimeException('"queue-base-dir" points to a directory that does not exist.');
+
+        $this->notifyStatus = self::NOTIFY_MANAGER_INITIALIZED;
+
+        $this->config = $config;
+        $this->queueBaseDir =  rtrim(realpath($this->config['queue-base-dir']), "/\\").DIRECTORY_SEPARATOR;
+        $this->observers = $observers;
+    }
+
+    /**
+     * @param array $config
+     * @param array $observers
+     * @return UglyQueueManager
+     */
+    public static function init(array $config, array $observers = array())
+    {
+        /** @var \DCarbone\UglyQueueManager $manager */
+        $manager = new static($config, array());
+
+        $manager->observers = $observers;
+
+        $manager->notify();
+
+        /** @var \DCarbone\UglyQueue $uglyQueue */
+
+        foreach(glob($manager->queueBaseDir.DIRECTORY_SEPARATOR.'*', GLOB_ONLYDIR) as $queueDir)
+        {
+            // Try to avoid looking at hidden directories or magic dirs such as '.' and '..'
+            $split = preg_split('#[/\\]+#', $queueDir);
+            if (strpos(end($split), '.') === 0)
+                continue;
+
+            if (file_exists($queueDir.DIRECTORY_SEPARATOR.self::UGLY_QUEUE_SERIALIZED_NAME))
+                $uglyQueue = unserialize(file_get_contents($queueDir.DIRECTORY_SEPARATOR.self::UGLY_QUEUE_SERIALIZED_NAME));
+            else
+                $uglyQueue = UglyQueue::queueWithGroupDirectoryPathAndObservers($queueDir, $manager->observers);
+
+            $manager->addQueue($uglyQueue);
+        }
+
+        return $manager;
+    }
+
+    /**
+     * @param UglyQueue $uglyQueue
+     * @return \DCarbone\UglyQueueManager
+     * @throws \InvalidArgumentException
+     */
+    public function addQueue(UglyQueue $uglyQueue)
+    {
+        if ($this->queueExistsByName($uglyQueue->name))
+            throw new \InvalidArgumentException('Queue named "'.$uglyQueue->name.'" already exists in this manager.');
+
+
+        $this->queues[$uglyQueue->name] = $uglyQueue;
+
+        $this->notifyStatus = self::NOTIFY_QUEUE_ADDED;
+        $this->notify();
+
+        return $this;
+    }
+
+    /**
+     * @param $path
+     * @return \DCarbone\UglyQueueManager
+     */
+    public function addQueueAtPath($path)
+    {
+        $uglyQueue = UglyQueue::queueWithGroupDirectoryPathAndObservers($path, $this->observers);
+
+        return $this->addQueue($uglyQueue);
+    }
+
+    /**
+     * @param UglyQueue $uglyQueue
+     * @return \DCarbone\UglyQueueManager
+     */
+    public function removeQueue(UglyQueue $uglyQueue)
+    {
+        if ($this->queueExistsByName($uglyQueue->name))
+            unset($this->queues[$uglyQueue->name]);
+
+        return $this;
+    }
+
+    /**
+     * @param string $name
+     * @return \DCarbone\UglyQueueManager
+     */
+    public function removeQueueByName($name)
+    {
+        if ($this->queueExistsByName($name))
+        {
+            unset($this->queues[$name]);
+            $this->notifyStatus = self::NOTIFY_QUEUE_REMOVED;
+            $this->notify();
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param string $name
+     * @return \DCarbone\UglyQueue
+     * @throws \InvalidArgumentException
+     */
+    public function &getQueueWithName($name)
+    {
+        if (isset($this->queues[$name]))
+            return $this->queues[$name];
+
+        throw new \InvalidArgumentException('Argument 1 expected to be valid queue name.');
+    }
+
+    /**
+     * @param string $name
+     * @return bool
+     */
+    public function queueExistsByName($name)
+    {
+        return isset($this->queues[$name]);
+    }
+
+    /**
+     * @return array
+     */
+    public function getQueueList()
+    {
+        return array_keys($this->queues);
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Receive update from subject
+     * @link http://php.net/manual/en/splobserver.update.php
+     *
+     * @param \SplSubject $subject The SplSubject notifying the observer of an update.
+     * @return void
+     */
+    public function update(\SplSubject $subject)
+    {
+        for ($i = 0, $count = count($this->observers); $i < $count; $i++)
+        {
+            $this->observers[$i]->notify($subject);
+        }
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Attach an SplObserver
+     * @link http://php.net/manual/en/splsubject.attach.php
+     *
+     * @param \SplObserver $observer The SplObserver to attach.
+     * @return void
+     */
+    public function attach(\SplObserver $observer)
+    {
+        if (!in_array($observer, $this->observers, true))
+            $this->observers[] = $observer;
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Detach an observer
+     * @link http://php.net/manual/en/splsubject.detach.php
+     *
+     * @param \SplObserver $observer The SplObserver to detach.
+     * @return void
+     */
+    public function detach(\SplObserver $observer)
+    {
+        $idx = array_search($observer, $this->observers, true);
+        if ($idx !== false)
+            unset($this->observers[$idx]);
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Notify an observer
+     * @link http://php.net/manual/en/splsubject.notify.php
+     *
+     * @return void
+     */
+    public function notify()
+    {
+        for ($i = 0, $count = count($this->observers); $i < $count; $i++)
+        {
+            $this->observers[$i]->notify($this);
+        }
+    }
+}