0.2.0 2016-12-28 14:50 UTC


This library will build a Multipart-encoded string suitable for use in HTTP requests.


Requiring from composer.json:

  "p3k/multipart": "*"
// Using composer...

// ...or requiring directly

// Create a new Multipart object
$multipart = new p3k\Multipart();

// Example POST data
$params = [
  'category' => [
  'name' => 'test',
  'nested' => [
    'foo' => [
    'bar' => 'foo'

// Add the params to the request

// You can add files too!
$multipart->addFile('photo', '/tmp/example.jpg', 'image/jpeg');

// Set up curl
$ch = curl_init('http://localhost:8000/server.php');
curl_setopt($ch, CURLOPT_POST, true);

// Set the POSTFIELDS to the result of this object
curl_setopt($ch, CURLOPT_POSTFIELDS, $multipart->data());

// You'll also need to set the Content-Type header
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
  'Content-type: ' . $multipart->contentType()



The built-in cURL library does not properly encode values that are arrays when it builds a multipart request. For example, this request results in a "Notice: Array to string conversion" and the value of the parameter is "Array":

$params = array(
  'category' => [

$ch = curl_init('http://localhost:8000/server.php');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $params);

See PHP Bugs:

This library can be used in place of cURL's built-in encoding.


You can test receiving this payload with the PHP and Ruby servers provided in this project.

To run the PHP server:

cd servers
php -S localhost:8000

This will run the built-in PHP web server listening on port 8000. Run the example code above and you will see the $_POST variable populated with the request.

To run the Ruby server, make sure you bundle install sinatra, then:

cd servers
ruby server.rb

Then you can post to http://localhost:4567/upload and you will see the JSON representation of the object that is posted.