Transloadit.php

<?php
/**
 * Transloadit.php
 */

/**
 * Transloadit class
 *
 * usage:
 *
 * $auth_key = 'your auth key';
 * $auth_secret = 'your auth secret';
 * $steps = array(
 *   'convert_urls' => array(
 * 		'robot' => '/html/convert',
 * 		'url' => 'http://twitter.com',
 * 	),
 * 	'resize_images' => array(
 * 		'use' => 'convert_urls',
 * 		'robot' => '/image/resize',
 * 		'format' => 'jpg',
 * 	),
 * );
 *
 * $T = new Transloadit( $auth_key, $auth_secret, $steps );
 * if ( ! $T->auth() ) {
 * 	exit('error');
 * }
 * echo $T->getAssenblyUrl();
 */
class Transloadit
{
	const API_URL = 'http://api2.transloadit.com/assemblies';

	private $_auth_key = null;
	private $_auth_secret = null;
	private $_expires = null;
	private $_steps = null;
	private $_assembly_url = null;
	private $_assembly_id = null;
	private $_auth_res = null;
	private $_auth_obj = null;

	public function __construct( $auth_key, $auth_secret, $steps = array(), $expires = '+1 hour' ){
		$this->_auth_key = $auth_key;
		$this->_auth_secret = $auth_secret;
		$this->_steps = $steps;
		$this->_expires = $expires;
		return true;
	}

	public function auth() {
		$params = json_encode( array(
			'auth' => array(
				'expires' => gmdate( 'Y/m/d H:i:s+00:00', strtotime( $this->_expires ) ),
				'key' => $this->_auth_key,
			),
			'steps' => $this->_steps,
		) );
		$signature = hash_hmac( 'sha1', $params, $this->_auth_secret );
		$data = array(
			'params' => $params,
			'signature' => $signature,
		);

		$this->_auth_res = $this->_post( self::API_URL, $data );
		$this->_auth_obj = json_decode( $this->_auth_res );

		if ( ! $this->_auth_obj || ! isset( $this->_auth_obj->assembly_url ) ) {
			return false;
		}
		$this->_assembly_url = $this->_auth_obj->assembly_url;
		$this->_assembly_id = $this->_auth_obj->assembly_id;

		return true;
	}

	public function getAssenblyUrl() {
		return $this->_assembly_url;
	}

	public function getAssenblyId() {
		return $this->_assembly_id;
	}

	public function getAuthObj() {
		return $this->_auth_obj;
	}

	public function getAuthRes() {
		return $this->_auth_res;
	}

	private function _post ( $url, $data = array() ) {
		return file_get_contents( $url, false, stream_context_create(
			array(
				'http'=>array(
					'method' => 'POST',
					'header' => "Content-type: application/x-www-form-urlencoded\r\n",
					'content'=> http_build_query( $data ),
					'ignore_errors' => true,
				)
			)
		));
	}
}