Creating a POST request using file handlers for file content

POST Request with File Resource

<?php

# base code found here: http://stackoverflow.com/questions/3085990/post-a-file-string-using-curl-in-php

$delimiter = '----WebKitFormBoundary'.uniqid();
$data = create_post($delimiter, array(
    'bingo' => 'yes'
), array(
    'file' => array(
        'filename' => 'data.txt',
        'type' => 'application/octet-stream',
        'content' => '@data.txt',
        //'content' => fopen('data.txt', 'rb'),
        //'content' => 'raw contents',
    )
));

$handle = curl_init('http://requestb.in/1717eay1');
curl_setopt($handle, CURLOPT_POST, true);
curl_setopt($handle, CURLOPT_HTTPHEADER , array(
    'Content-Type: multipart/form-data; boundary=' . $delimiter,
    'Content-Length: ' . strlen($data)));
curl_setopt($handle, CURLOPT_POSTFIELDS, $data);
curl_exec($handle);

/**
 * @param array $postFields The KVPs you want as post data
 * @param array $fileFields The objects of each file: name => array(type=>'mime/type',content=>'raw data|resource',filename=>'file.csv')
 */
function create_post($delimiter, $postFields, $fileFields = array()){
    // form field separator
    $eol = "\r\n";
    $data = '';
    // populate normal fields first (simpler)
    foreach ($postFields as $name => $content) {
        $data .= "--$delimiter" . $eol;
        $data .= 'Content-Disposition: form-data; name="' . $name . '"';
        $data .= $eol.$eol; // note: double endline
        $data .= $content;
        $data .= $eol;
    }
    // populate file fields
    foreach ($fileFields as $name => $file) {
        $data .= "--$delimiter" . $eol;
        // fallback on var name for filename
        if (!array_key_exists('filename', $file))
        {
            $file['filename'] = $name;
        }
        // "filename" attribute is not essential; server-side scripts may use it
        $data .= 'Content-Disposition: form-data; name="' . $name . '";' .
            ' filename="' . $file['filename'] . '"' . $eol;
        // this is, again, informative only; good practice to include though
        $data .= 'Content-Type: ' . $file['type'] . $eol;
        // this endline must be here to indicate end of headers
        $data .= $eol;
        // the file itself (note: there's no encoding of any kind)
        if (is_resource($file['content'])){
            // rewind pointer
            rewind($file['content']);
            // read all data from pointer
            while(!feof($file['content'])) {
                $data .= fgets($file['content']);
            }
            $data .= $eol;
        }else {
            // check if we are loading a file from full path
            if (strpos($file['content'], '@') === 0){
                $file_path = substr($file['content'], 1);
                $fh = fopen(realpath($file_path), 'rb');
                if ($fh) {
                    while (!feof($fh)) {
                        $data .= fgets($fh);
                    }
                    $data .= $eol;
                    fclose($fh);
                }
            }else {
                // use data as provided
                $data .= $file['content'] . $eol;
            }
        }
    }
    // last delimiter
    $data .= "--" . $delimiter . "--$eol";
    return $data;
}

saved

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