Drupal form api file upload using drupal_http_request - forms

Question

I am trying to post a file uploaded in drupal form to another server through a post request using drupal_http_request.
I am not sure where am I making a mistake but the file doesnot seem to get posted. What should I be doing.?
I use the following code.
$options = array(
'method' => 'POST',
'data' => drupal_http_build_query($data),
'timeout' => $connect_ariba_values['timeout'],
'headers' => array('Content-Type' => 'multipart/form-data'),
);
$response = drupal_http_request($url, $options);
multipart/form-data doesnot seem to work.

Answer 1

Source: https://drupal.org/user/194073
<?php
$boundary = md5(uniqid());
$post_data = array(
'name' => 'Ayesh',
'file' => '/var/www/test/test.png',
);
$options = array(
'method' => 'POST',
'data' => multipart_encode($boundary, $post_data),
'timeout' => $connect_ariba_values['timeout'],
'headers' => array('Content-Type' => "multipart/form-data; boundary=$boundary"),
);
$response = drupal_http_request($url, $options);
// Function to encode text data.
function multipart_enc_text($name, $value){
return "Content-Disposition: form-data; name=\"$name\"\r\n\r\n$value\r\n";
}
// Function to multipart encode a file from a give path.
function multipart_enc_file($path){
if (substr($path, 0, 1) == "#") $path = substr($path, 1);
$filename = basename($path);
$mimetype = "application/octet-stream";
$data = "Content-Disposition: form-data; name=\"file\"; filename=\"$filename\"\r\n"; // "file" key.
$data .= "Content-Transfer-Encoding: binary\r\n";
$data .= "Content-Type: $mimetype\r\n\r\n";
$data .= file_get_contents($path) . "\r\n";
return $data;
}
// base function to encode a data array.
function multipart_encode($boundary, $params){
$output = "";
foreach ($params as $key => $value){
$output .= "--$boundary\r\n";
if ($key == 'file'){
$output .= multipart_enc_file($value);
} else $output .= multipart_enc_text ($key, $value);
}
$output .="--$boundary--";
return $output;
}
In the server, file will be available in $_FILES['file'], and other POST data will be available in their relevant keys.
I didn't test the code. I just found the code in drupal forum, changed it to work with Drupal 6 and 7.