PHP | How to get headers from GET Request?

Question

I want to display the received headers from the GET Request that I send,

PHP:

<?php
$opts = array(
'http'=>array(
'method'=>"GET",
'header'=>"User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:51.0) Gecko/20100101 Firefox/51.0"
));
$context = stream_context_create($opts);
$url = "http://spys.me/proxy.txt";
// instead of file_get_contents
$data = getallheaders($url, false, $context);

echo $data;

Answer 1

You can get all the headers like this

foreach (getallheaders() as $name => $value) {
    echo "$name: $value\n";
}

Answer 2

How about simple var_dump()?

var_dump(getallheaders());