A class to get working days between two dates...

WorkingDays.php

<?php

namespace App\Services;

use DateInterval;
use DatePeriod;
use DateTime;
use Exception;
use Illuminate\Support\Facades\Cache;

class WorkingDays
{
    const DISPLAY_DATE_FORMAT = 'D, Y-M-d';
    const HOLIDAYS_DATE_FORMAT = 'Y-m-d';
    const HOLIDAYS_CACHE_MINUTES = 60 * 24 * 30;

    /**
     * @var string
     */
    private $dateFrom;

    /**
     * @var string
     */
    private $dateTo;

    /**
     * WorkingDays constructor.
     * @param string $dateFrom
     * @param string $dateTo
     */
    public function __construct($dateFrom, $dateTo)
    {
        $this->dateFrom = $dateFrom;
        $this->dateTo = $dateTo;
    }

    /**
     * @return DateTime[]
     * @throws Exception
     */
    public function __toArray()
    {
        $holidays = $this->getHolidays();
        $startDate = new DateTime($this->dateFrom);
        $endDate = new DateTime($this->dateTo);
        $interval = new DateInterval('P1D');
        $dateRange = new DatePeriod($startDate, $interval, $endDate);
        $results = [];
        /** @var DateTime $date */
        foreach ($dateRange as $date) {
            if ($date->format('N') < 6 &&
                !in_array($date->format(self::HOLIDAYS_DATE_FORMAT), $holidays)) {
                $results[] = $date;
            }
        }
        return $results;
    }

    /**
     * @return array
     */
    protected function getHolidays()
    {
        $url = 'https://www.gov.uk/bank-holidays.json';
        $holidaysData = Cache::get($url);
        if (!$holidaysData) {
            $holidaysData = file_get_contents($url);
            Cache::put($url, $holidaysData, self::HOLIDAYS_CACHE_MINUTES);
        }
        $holidaysArray = json_decode($holidaysData, true);
        $holidays = [];
        foreach ($holidaysArray['england-and-wales']['events'] as $event) {
            $holidays[] = $event['date'];
        }
        return $holidays;
    }

}