Highlights

Period is PHP's Time Range class. It is based on Resolving Feature Envy in the Domain by Mathias Verraes and extends the concept to cover all basic operations regarding time ranges.

Treats date and time range as immutable value objects
Exposes named constructors to ease time range creation
Covers all basic manipulations related to time range
Framework-agnostic

Features

easy instance creation

use League\Period\Period;

//do
$interval = Period::around('2014-01-01 08:00:25', '1 HOUR');

//instead of doing
$date = new DateTimeImmutable('2014-01-01 08:00:25');
$duration = new DateInterval('PT1H');
$startDate = $date->sub($duration);
$endDate = $date->add($duration);

$interval = new Period($startDate, $endDate);

To help you start working with Period objects, the library comes bundled with many more named constructors to ease manipulating datetime intervals.

iterating over the interval made simple

You can return selected datepoints inside the interval

foreach (Period::fromMonth(2014, 10)->getDatePeriod('1 DAY') as $datepoint) {
    echo $datepoint->format('Y-m-d');
}

or split the interval into smaller Period objects

foreach (Period::fromMonth(2014, 10)->split('1 DAY') as $period) {
    foreach ($period->getDatePeriod('1 HOUR') as $datepoint) {
    	echo $datepoint->format('Y-m-d H:i:s');
    }
}

The library also allow iterating backwards over the interval.

compare intervals and datepoints

You can compare time ranges based on their duration and/or their datepoints.

$period = Period::after('2014-01-01', '1 WEEK');
$altPeriod = Period::fromIsoWeek(2014, 3);
$period->durationEquals($altPeriod); //returns true
$period->equals($altPeriod); //returns false
$period->contains($altPeriod); //returns false
$period->contains('2014-01-02'); //returns true

Modifying time ranges

Period is an immutable value object. Any change to the object returns a new object.

$period = Period::before('2014-01-07', '1 WEEK');
$altPeriod = $period->endingOn('2014-02-03');
$period->contains($altPeriod); //return false;
$altPeriod->durationGreaterThan($period); //return true;

formatting

Format and export your Period instance following standardized format.

$period = Period::after('2014-10-03 08:00:00', 3600);

echo $period; // 2014-10-03T06:00:00.000000Z/2014-10-03T07:00:00.000000Z
echo $period->format('Y-m-d H:i:s'); // [2014-10-03 08:00:00, 2014-10-03 09:00:00)
echo json_encode($period, JSON_PRETTY_PRINT);
// {
//     "startDate": "2014-10-03T06:00:00.000000Z",
//     "endDate": "2014-10-03T07:00:00.000000Z"
// }

Accessing Gaps between intervals

use League\Period\Period;
use League\Period\Sequence;

$sequence = new Sequence(
    new Period('2018-01-01', '2018-01-31'),
    new Period('2017-01-01', '2017-01-31'),
    new Period('2020-01-01', '2020-01-31')
);
$gaps = $sequence->getGaps(); // a new Sequence object
count($gaps); // 2

Sequence is a Period container and collection class.

Questions?

Period was created by Ignace Nyamagana Butera. Find him on Twitter at @nyamsprod.