Merge pull request #580 from resurtm/mutex-10050

extensions/mutex/composer.json

+{
+	"name": "yiisoft/yii2-mutex",
+	"description": "Mutual exclusion extension for the Yii framework",
+	"keywords": ["yii", "mutex"],
+	"type": "library",
+	"license": "BSD-3-Clause",
+	"support": {
+		"issues": "https://github.com/yiisoft/yii2/issues?state=open",
+		"forum": "http://www.yiiframework.com/forum/",
+		"wiki": "http://www.yiiframework.com/wiki/",
+		"irc": "irc://irc.freenode.net/yii",
+		"source": "https://github.com/yiisoft/yii2"
+	},
+	"authors": [
+		{
+			"name": "resurtm",
+			"email": "resurtm@gmail.com"
+		}
+	],
+	"minimum-stability": "dev",
+	"require": {
+		"yiisoft/yii2": "*"
+	},
+	"autoload": {
+		"psr-0": { "yii\\mutex": "" }
+	}
+}

extensions/mutex/yii/mutex/DbMutex.php

+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\mutex;
+
+use Yii;
+use yii\db\Connection;
+use yii\base\InvalidConfigException;
+
+/**
+ * @author resurtm <resurtm@gmail.com>
+ * @since 2.0
+ */
+abstract class DbMutex extends Mutex
+{
+	/**
+	 * @var Connection|string the DB connection object or the application component ID of the DB connection.
+	 * After the Mutex object is created, if you want to change this property, you should only assign
+	 * it with a DB connection object.
+	 */
+	public $db = 'db';
+
+	/**
+	 * Initializes generic database table based mutex implementation.
+	 * @throws InvalidConfigException if [[db]] is invalid.
+	 */
+	public function init()
+	{
+		parent::init();
+		if (is_string($this->db)) {
+			$this->db = Yii::$app->getComponent($this->db);
+		}
+		if (!$this->db instanceof Connection) {
+			throw new InvalidConfigException('Mutex::db must be either a DB connection instance or the application component ID of a DB connection.');
+		}
+	}
+}

extensions/mutex/yii/mutex/FileMutex.php

+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\mutex;
+
+use Yii;
+use yii\base\InvalidConfigException;
+
+/**
+ * @author resurtm <resurtm@gmail.com>
+ * @since 2.0
+ */
+class FileMutex extends Mutex
+{
+	/**
+	 * @var string the directory to store mutex files. You may use path alias here.
+	 * If not set, it will use the "mutex" subdirectory under the application runtime path.
+	 */
+	public $mutexPath = '@runtime/mutex';
+	/**
+	 * @var resource[] stores all opened lock files. Keys are lock names and values are file handles.
+	 */
+	private $_files = array();
+
+
+	/**
+	 * Initializes mutex component implementation dedicated for UNIX, GNU/Linux, Mac OS X, and other UNIX-like
+	 * operating systems.
+	 * @throws InvalidConfigException
+	 */
+	public function init()
+	{
+		if (stripos(php_uname('s'), 'win') === 0) {
+			throw new InvalidConfigException('FileMutex does not have MS Windows operating system support.');
+		}
+		$this->mutexPath = Yii::getAlias($this->mutexPath);
+		if (!is_dir($this->mutexPath)) {
+			mkdir($this->mutexPath, 0777, true);
+		}
+	}
+
+	/**
+	 * This method should be extended by concrete mutex implementations. Acquires lock by given name.
+	 * @param string $name of the lock to be acquired.
+	 * @param integer $timeout to wait for lock to become released.
+	 * @return boolean acquiring result.
+	 */
+	protected function acquireLock($name, $timeout = 0)
+	{
+		$file = fopen($this->mutexPath . '/' . md5($name) . '.lock', 'w+');
+		if ($file === false) {
+			return false;
+		}
+		$waitTime = 0;
+		while (!flock($file, LOCK_EX | LOCK_NB)) {
+			$waitTime++;
+			if ($waitTime > $timeout) {
+				fclose($file);
+				return false;
+			}
+			sleep(1);
+		}
+		$this->_files[$name] = $file;
+		return true;
+	}
+
+	/**
+	 * This method should be extended by concrete mutex implementations. Releases lock by given name.
+	 * @param string $name of the lock to be released.
+	 * @return boolean release result.
+	 */
+	protected function releaseLock($name)
+	{
+		if (!isset($this->_files[$name]) || !flock($this->_files[$name], LOCK_UN)) {
+			return false;
+		} else {
+			fclose($this->_files[$name]);
+			unset($this->_files[$name]);
+			return true;
+		}
+	}
+}

extensions/mutex/yii/mutex/Mutex.php

+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\mutex;
+
+use Yii;
+use yii\base\Component;
+
+/**
+ * @author resurtm <resurtm@gmail.com>
+ * @since 2.0
+ */
+abstract class Mutex extends Component
+{
+	/**
+	 * @var boolean whether all locks acquired in this process (i.e. local locks) must be released automagically
+	 * before finishing script execution. Defaults to true. Setting this property to true means that all locks
+	 * acquire in this process must be released in any case (regardless any kind of errors or exceptions).
+	 */
+	public $autoRelease = true;
+	/**
+	 * @var string[] names of the locks acquired in the current PHP process.
+	 */
+	private $_locks = array();
+
+
+	/**
+	 * Initializes the mutex component.
+	 */
+	public function init()
+	{
+		if ($this->autoRelease) {
+			$mutex = $this;
+			$locks = &$this->_locks;
+			register_shutdown_function(function () use ($mutex, &$locks) {
+				foreach ($locks as $lock) {
+					$mutex->release($lock);
+				}
+			});
+		}
+	}
+
+	/**
+	 * @param string $name of the lock to be acquired. Must be unique.
+	 * @param integer $timeout to wait for lock to be released. Defaults to zero meaning that method will return
+	 * false immediately in case lock was already acquired.
+	 * @return boolean lock acquiring result.
+	 */
+	public function acquire($name, $timeout = 0)
+	{
+		if ($this->acquireLock($name, $timeout)) {
+			$this->_locks[] = $name;
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	/**
+	 * Release acquired lock. This method will return false in case named lock was not found.
+	 * @param string $name of the lock to be released. This lock must be already created.
+	 * @return boolean lock release result: false in case named lock was not found..
+	 */
+	public function release($name)
+	{
+		if ($this->releaseLock($name)) {
+			$index = array_search($name, $this->_locks);
+			if ($index !== false) {
+				unset($this->_locks[$index]);
+			}
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	/**
+	 * This method should be extended by concrete mutex implementations. Acquires lock by given name.
+	 * @param string $name of the lock to be acquired.
+	 * @param integer $timeout to wait for lock to become released.
+	 * @return boolean acquiring result.
+	 */
+	abstract protected function acquireLock($name, $timeout = 0);
+
+	/**
+	 * This method should be extended by concrete mutex implementations. Releases lock by given name.
+	 * @param string $name of the lock to be released.
+	 * @return boolean release result.
+	 */
+	abstract protected function releaseLock($name);
+}

extensions/mutex/yii/mutex/MysqlMutex.php

+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\mutex;
+
+use Yii;
+use yii\base\InvalidConfigException;
+
+/**
+ * @author resurtm <resurtm@gmail.com>
+ * @since 2.0
+ */
+class MysqlMutex extends Mutex
+{
+	/**
+	 * Initializes MySQL specific mutex component implementation.
+	 * @throws InvalidConfigException if [[db]] is not MySQL connection.
+	 */
+	public function init()
+	{
+		parent::init();
+		if ($this->db->driverName !== 'mysql') {
+			throw new InvalidConfigException('In order to use MysqlMutex connection must be configured to use MySQL database.');
+		}
+	}
+
+	/**
+	 * This method should be extended by concrete mutex implementations. Acquires lock by given name.
+	 * @param string $name of the lock to be acquired.
+	 * @param integer $timeout to wait for lock to become released.
+	 * @return boolean acquiring result.
+	 * @see http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_get-lock
+	 */
+	protected function acquireLock($name, $timeout = 0)
+	{
+		return (boolean)$this->db
+			->createCommand('SELECT GET_LOCK(:name, :timeout)', array(':name' => $name, ':timeout' => $timeout))
+			->queryScalar();
+	}
+
+	/**
+	 * This method should be extended by concrete mutex implementations. Releases lock by given name.
+	 * @param string $name of the lock to be released.
+	 * @return boolean release result.
+	 * @see http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
+	 */
+	protected function releaseLock($name)
+	{
+		return (boolean)$this->db
+			->createCommand('SELECT RELEASE_LOCK(:name)', array(':name' => $name))
+			->queryScalar();
+	}
+}