date_range.php

<?php 

function getRangeDate($start, $end, $increment = '+1 days') {
	$current = strtotime($start);
	$end     = strtotime($end);
	$results = [];	

	while($current < $end){        
        $results[] = date('Y-m-d', $current);	
        $current =   strtotime($increment, strtotime(date('Y-m-d', $current)));
	}
	return  $results;
}

$start = date('Y-m-d', strtotime('- 7 day'));
$end   = date('Y-m-d');

print_r(getRangeDate($start, $end));