Posting to a file using CURL... Not taking variables - php

Question

Posting to a file using Curl
I'm trying to post to a file as soon as user enters a website assuming they have clicked from an ad.
Example url = http://myFabSite.com/?tr=213
This is what I'm trying but its not capturing the tr URL variable or the referrer:
if($_GET['tr']){
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "http://myFabSite.com/actions/tracksAds.php");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_POST, true);
$data = array(
'referrer' => $_SERVER['HTTP_REFERER'],
'track_code' => $_GET['tr']
);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
$output = curl_exec($ch);
$info = curl_getinfo($ch);
curl_close($ch);
}
trackAds.php:
$mysqli = dbConnect();
$referrer = $mysqli->real_escape_string(urldecode(trim($_REQUEST['referrer'])));
$track_code = $mysqli->real_escape_string($_REQUEST['track_code']);
$query = "insert into ad_tracking ( tracking_code, referrer ) VALUES ( '$track_code', '$referrer' )";
$result = $mysqli->query($query);
Anything obvious?
UPDATE
This is from print_r($data);
Array
(
[referrer] => none
[track_code] => fb1
)
This is $query from trackAds.php
insert into ad_tracking ( tracking_code, referrer ) VALUES ( '', '' )
So, the array is not being passed, either at all or correctly, to trackAds.php

Answer 1

You're missing quotes in $_GET[tr] on the first line. Change it to $_GET['tr'].
Also, use $_POST instead of $_REQUEST in trackAds.php. There's a great chance here that you are inadvertently getting a cookie value instead of a POST value, or simply have the wrong data in $_REQUEST. See this page in the documentation.

Answer 2

Actually found a different method which works ok, still no clue why the other doesn't.
This assumes PHP 5+
$url = 'http://myFabSite.com/actions/tracksAds.php';
$data = array('referrer' => $_SERVER['HTTP_REFERER'], 'track_code' => $_GET['tr']);
// use key 'http' even if you send the request to https://...
$options = array(
'http' => array(
'header' => "Content-type: application/x-www-form-urlencoded\r\n",
'method' => 'POST',
'content' => http_build_query($data),
),
);
$context = stream_context_create($options);
$result = file_get_contents($url, false, $context);