Highlights

Period is PHP's Time Range class. Based on ideas from Resolving Feature Envy in the Domain by Mathias Verraes, this package extends the concept to cover all basic operations regarding time ranges.

Uses Immutable Value Objects
Uses named constructors to ease object creation
Covers all basic manipulations related to time range
Enables working with simple or complex time ranges logic

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);

$interval = Period::fromDate($startDate, $endDate);

To help you start working with Period objects, the library comes bundled with many more named constructors to ease datepoint, duration and intervals creation.

iterating over the interval made simple

You can return selected date endpoints inside the interval

use League\Period\Period;

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

or split the interval into smaller Period objects

use League\Period\Period;

foreach (Period::fromMonth(2014, 10)->splitForward('1 DAY') as $period) {
    foreach ($period->dateRange('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, their datepoints and even their boundary types.

use League\Period\Bounds;
use League\Period\Period;

$period = Period::after('2014-01-01', '1 MONTH', Bounds::IncludeAll);
$altPeriod = Period::after('2014-01-01', '1 MONTH', Bounds::ExcludeAll);
$period->durationEquals($altPeriod), //returns true
$period->equals($altPeriod), //returns false
$period->contains($altPeriod), //returns true
$altPeriod->contains($period), //return false
$period->contains('2014-01-10'), //returns true
Datepoint::create('2014-02-10')->isDuring($period) //returns false

Modifying time ranges

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

use League\Period\Period;

$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.

use League\Period\Bounds;
use League\Period\Period;

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

echo $period; // 2014-10-03T06:00:00.000000Z/2014-10-03T07:00:00.000000Z
echo $period->toIso80000('Y-m-d H:i:s'); // [2014-10-03 08:00:00, 2014-10-03 09:00:00)
echo json_encode($period, JSON_PRETTY_PRINT);
// {
//     "startDate": "2014-10-03T06:00:00.000000Z",
//     "endDate": "2014-10-03T07:00:00.000000Z",,
//     "startDateIncluded": true,
//    "endDateIncluded": false
// }

Accessing Gaps between intervals

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

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

Sequence is a Period container and collection class.

Displaying intervals using a GanttChart

Using the feature present under the League\Period\Chart you can visualize on the console the interactions betweens multiple League\Period\Period and/or League\Period\Sequence instances.

use League\Period\Bounds;
use League\Period\Chart;
use League\Period\Period;
use League\Period\Sequence;

$sequence = new Sequence(
    Period::fromMonth(2021, 1, Bounds::IncludeAll),
    Period::fromDate('2021-02-10', '2021-02-20', Bounds::ExcludeAll),
    Period::fromMonth(2021, 3, Bounds::IncludeStartExcludeEnd),
    Period::after('2021-01-20', '1 month 20 days', Bounds::ExcludeStartIncludeEnd)
);
$intersections = $sequence->intersections();

$labelGenerator = new Chart\LatinLetter('f');
$labelGenerator = new Chart\AffixLabel($labelGenerator, 'Interval ', '.');

$dataset = Chart\Dataset::fromItems($sequence, $labelGenerator)
    ->append("Intersections.", $intersections);

$chart = new Chart\GanttChart();
$chart->stroke($dataset);

will output something like this:

    Interval f. [-------------------]                                       
    Interval g.                           (------)                          
    Interval h.                                        [-------------------)
    Interval i.             (---------------------------------]             
 Intersections.             (-------]     (------)     [------]   

Questions?

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