$_FILES empty, curl with file upload - php

Question

I've been banging my head against the wall on this one. I feel like my problem is something really silly, but I just can't figure out what.
I have a proxy script, which is handling everything (POST data and uploads).
When I print_r($_FILES) on the back-end server, it's an empty array, and $_POST contains the file path.
$ch = curl_init();
$options = array(
CURLOPT_HEADER => 1,
CURLOPT_HTTPHEADER => array(
"Host: {$host}",
"Cache-Control: no-cache"
),
CURLOPT_RETURNTRANSFER => true,
CURLOPT_SSL_VERIFYHOST => false,
CURLOPT_SSL_VERIFYPEER => 0,
CURLOPT_URL => "http://{$this->config->ipAddress}{$url}",
CURLOPT_FOLLOWLOCATION => false,
CURLOPT_COOKIE => $cookie_string,
CURLOPT_USERAGENT => $_SERVER["HTTP_USER_AGENT"]
);
if (! empty($_POST)) {
if (! empty($_FILES)) {
//$options[CURLOPT_HTTPHEADER][] = "Content-type: multipart/form-data";
$files = "";
foreach ($_FILES as $fid => $file) {
$files .= "{$fid}=#" . $file["tmp_name"] . ";type={$file["type"]};name={$file["name"]}&";
}
}
$postString = (! empty($files) ? $files : '') . http_build_query($_POST);
$options[CURLOPT_POST] = 1;
$options[CURLOPT_POSTFIELDS] = $postString;
}
curl_setopt_array($ch, $options);
$output = curl_exec($ch);
$info = curl_getinfo($ch);
curl_close($ch);
The reason I'm using http_build_query instead of just feeding an array is because we will encounter a multidimensional array.
Thanks!

Answer 1

I'm willing to bet your form enctype isn't "multipart/form-data" b/c your not passing the post string as an array.
http://php.net/manual/en/function.curl-setopt.php search for "CURLOPT_POSTFIELDS"
below is an excerpt from that page.
"If value is an array, the Content-Type header will be set to multipart/form-data. As of PHP 5.2.0, value must be an array if files are passed to this option with the # prefix."
You can find out what is going on with the curl by setting the curl option "curl_setopt($ch, CURLOPT_VERBOSE, TRUE); " and then "print_r( curl_getinfo($ch) );" after the "curl_exec($ch);" and it will output all the information about the request and response.