Locker\Data\Analytics\Analytics::buildDates PHP Method

    private function buildDates($since = '', $until = '')
    {
        $dates = [];
        if ($since !== '' || $until !== '') {
            $timestamp = [];
            if ($since !== '') {
                $timestamp['$gte'] = $since;
            }
            if ($until !== '') {
                $timestamp['$lte'] = $until;
            }
            $dates = ['timestamp' => $timestamp];
        }
        return $dates;
    }