README

Description

Various locking mechanisms, providing atomic locks.

Installation

Installation via composer:

composer require tigron/skeleton-lock

Configuration

In the default case, skeleton-lock assumes it is running an application on a single node, and using an RDBMS which supports locks (e.g. MySQL/ MariaDB's GET_LOCK()).

However, this is not always supported, for example when running a clustered database.

The following mechanisms are supported:

• database (default)
• file
• memcache
• memcached

This can be configured via Config:

\Skeleton\Lock\Config::$locking = 'database';

Of course, each mechanism requires the supporting skeleton package to be installed as well, and requires the settings for that specific mechanism to be defined.

\Skeleton\Object\Config::$cache_handler_config = [
	'hostname' => '127.0.0.1', // memcache/memcached
	'port' => '12211', // memcache/memcached
	'dsn' => 'mysqli://user@database/table', // database
	'path' => '/path/', // file
	'expire' => 10, // not supported for database
];

Note that not all mechanisms support all features. For example, database locks can not expire.

Usage

For getting a lock, you can either call obtain() or wait(), where the former will fail immediately if it can not get a lock, and the latter will retry until the specified timeout expired.

Releasing a lock is done with release().

Examples

Get the current handler, and wait for 5 seconds to acquire mylock:

\Skeleton\Lock\Handler::get()::wait('mylock', wait: 5);

Get the current handler, get mylock immediately and deal with potential failure:

try {
	$lock = \Skeleton\Lock\Handler::get();
	$lock::obtain('mylock');
} catch (\Skeleton\Lock\Exception\Failed $e) {
	echo 'Could not get the lock';
}

Releasing the lock we got earlier:

$lock::release('mylock');