> For the complete documentation index, see [llms.txt](https://docs.sonsofphp.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sonsofphp.com/components/clock.md).

# Clock

The Clock Component is a wrapper around PHP's native DateTime objects and functions. Using the Clock Component helps you test and keep everything a standard timezone

### Installation

```shell
composer require sonsofphp/clock
```

### Usage

#### SystemClock

The `SystemClock` is generally used in production. If you need check timestamps or manage dates and times, this is the Clock you want to use. Use Dependency Injection to make it easy to test with.

```php
<?php

use SonsOfPHP\Component\Clock\SystemClock;

$clock = new SystemClock();

$now = $clock->now(); // Returns a DateTimeImmutable object
```

#### FixedClock

The `FixedClock` is used for testing. Just set the time and inject into your class.

```php
<?php
use SonsOfPHP\Component\Clock\FixedClock;

$clock = new FixedClock();
$firstNow = $clock->now();
sleep(10);
$secondNow = $clock->now();

var_dump($firstNow === $secondNow); // true

// You can update the internal time at any time.
$clock->tick(); // Updates the internal clock to the curent time
$thridNow = $clock->now();

var_dump($firstNow === $secondNow); // still true
var_dump($firstNow === $thirdNow); // false
var_dump($thirdNow === $secondNow); // false

// You can also set the internal clock to whatever time you need it to be
$clock->tickTo('2022-04-20 04:20:00'); // format is "Y-m-d H:i:s"
```


---

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