# Rhumsaa\Uuid

[![Build Status](https://secure.travis-ci.org/ramsey/uuid.png)](http://travis-ci.org/ramsey/uuid)

A PHP 5.3+ library for generating and working with [RFC 4122][rfc4122] version
1, 3, 4, and 5 universally unique identifiers (UUID).

Much inspiration for this library came from the [Java][javauuid] and
[Python][pyuuid] UUID libraries.

Please see `docs/` for generated API documentation.

## Requirements

Some methods in this library have requirements due to integer size restrictions
on 32-bit and 64-bit builds of PHP. A 64-bit build of PHP and the [Moontoast\Math][]
library are recommended. However, this library is designed to work on 32-bit
builds of PHP without Moontoast\Math, with some degraded functionality. Please
check the API documention for more information.

If a particular requirement is not present, then a `Rhumsaa\Uuid\Exception\UnsatisfiedDependencyException`
is thrown, allowing one to catch a bad call in an environment where the call is
not supported and gracefully degrade.

## Examples

```php
<?php
require 'vendor/autoload.php';

use Rhumsaa\Uuid\Uuid;
use Rhumsaa\Uuid\Exception\UnsatisfiedDependencyException;

try {

    // Generate a version 1 (time-based) UUID
    $uuid1 = Uuid::uuid1();
    echo $uuid1 . "\n"; // e4eaaaf2-d142-11e1-b3e4-080027620cdd

    // Generate a version 3 (name-based and hashed with MD5) UUID
    $uuid3 = Uuid::uuid3(Uuid::NAMESPACE_DNS, 'php.net');
    echo $uuid3 . "\n"; // 11a38b9a-b3da-360f-9353-a5a725514269

    // Generate a version 4 (random) UUID
    $uuid4 = Uuid::uuid4();
    echo $uuid4 . "\n"; // 25769c6c-d34d-4bfe-ba98-e0ee856f3e7a

    // Generate a version 5 (name-based and hashed with SHA1) UUID
    $uuid5 = Uuid::uuid5(Uuid::NAMESPACE_DNS, 'php.net');
    echo $uuid5 . "\n"; // c4a760a8-dbcf-5254-a0d9-6a4474bd1b62

} catch (UnsatisfiedDependencyException $e) {

    // Some dependency was not met. Either the method cannot be called on a
    // 32-bit system, or it can, but it relies on Moontoast\Math to be present.
    echo 'Caught exception: ' . $e->getMessage() . "\n";

}
```

## Installation

The preferred method of installation is via [Packagist][], as this provides
the PSR-0 autoloader functionality. The following `composer.json` will download
and install the latest version of the Uuid library into your project:

```json
{
    "require": {
        "rhumsaa/uuid": "~2.2"
    }
}
```


[rfc4122]: http://tools.ietf.org/html/rfc4122
[javauuid]: http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html
[pyuuid]: http://docs.python.org/3/library/uuid.html
[packagist]: http://packagist.org/
[moontoast\math]: https://github.com/moontoast/math