The usage of the @filename API for file uploading is deprecated. Please use the CURLFile class instead

I believe it's as simple as changing your '@'.$filePath to use CurlFile instead.

$post = array('apikey' => 'key', 'mode' => 'document_photo', 'file' => new CurlFile($filePath));

The above worked for me.

Note: I work for HP.

Due to time pressure, I did a quick workaround when I integrated a third party API. You can find the code below.

$url: Domain and page to post to; for example http://www.snyggamallar.se/en/$params: array[key] = value format, just like you have in $post.

WARNING: Any value that begins with an @ will be treated as a file, which of course is a limitation. It does not cause any issues in my case, but please take it into consideration in your code.

static function httpPost($url, $params){    foreach($params as $k=>$p){        if (substr($p, 0, 1) == "@") { // Ugly            $ps[$k] = getCurlFile($p);        } else {            $ps[$k] = utf8_decode($p);        }    }    $ch = curl_init($url);    curl_setopt ($ch, CURLOPT_POST, true);    curl_setopt ($ch, CURLOPT_POSTFIELDS, $ps);    curl_setopt ($ch, CURLOPT_RETURNTRANSFER, true);    $res = curl_exec($ch);    return $res;}static function getCurlFile($filename){    if (class_exists('CURLFile')) {        return new CURLFile(substr($filename, 1));    }    return $filename;}