<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_Service_Amazon
* @subpackage Ec2
* @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id: Abstract.php 24594 2012-01-05 21:27:01Z matthew $
*/
/**
* @see Zend_Service_Amazon_Abstract
*/
require_once 'Zend/Service/Amazon/Abstract.php';
/**
* @see Zend_Service_Amazon_Ec2_Response
*/
require_once 'Zend/Service/Amazon/Ec2/Response.php';
/**
* @see Zend_Service_Amazon_Ec2_Exception
*/
require_once 'Zend/Service/Amazon/Ec2/Exception.php';
/**
* Provides the basic functionality to send a request to the Amazon Ec2 Query API
*
* @category Zend
* @package Zend_Service_Amazon
* @subpackage Ec2
* @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
abstract class Zend_Service_Amazon_Ec2_Abstract extends Zend_Service_Amazon_Abstract
{
/**
* The HTTP query server
*/
protected $_ec2Endpoint = 'ec2.amazonaws.com';
/**
* The API version to use
*/
protected $_ec2ApiVersion = '2009-04-04';
/**
* Signature Version
*/
protected $_ec2SignatureVersion = '2';
/**
* Signature Encoding Method
*/
protected $_ec2SignatureMethod = 'HmacSHA256';
/**
* Period after which HTTP request will timeout in seconds
*/
protected $_httpTimeout = 10;
/**
* @var string Amazon Region
*/
protected static $_defaultRegion = null;
/**
* @var string Amazon Region
*/
protected $_region;
/**
* An array that contains all the valid Amazon Ec2 Regions.
*
* @var array
*/
protected static $_validEc2Regions = array('eu-west-1', 'us-east-1');
/**
* Create Amazon client.
*
* @param string $access_key Override the default Access Key
* @param string $secret_key Override the default Secret Key
* @param string $region Sets the AWS Region
* @return void
*/
public function __construct($accessKey=null, $secretKey=null, $region=null)
{
if(!$region) {
$region = self::$_defaultRegion;
} else {
// make rue the region is valid
if(!empty($region) && !in_array(strtolower($region), self::$_validEc2Regions, true)) {
require_once 'Zend/Service/Amazon/Exception.php';
throw new Zend_Service_Amazon_Exception('Invalid Amazon Ec2 Region');
}
}
$this->_region = $region;
parent::__construct($accessKey, $secretKey);
}
/**
* Set which region you are working in. It will append the
* end point automaticly
*
* @param string $region
*/
public static function setRegion($region)
{
if(in_array(strtolower($region), self::$_validEc2Regions, true)) {
self::$_defaultRegion = $region;
} else {
require_once 'Zend/Service/Amazon/Exception.php';
throw new Zend_Service_Amazon_Exception('Invalid Amazon Ec2 Region');
}
}
/**
* Method to fetch the AWS Region
*
* @return string
*/
protected function _getRegion()
{
return (!empty($this->_region)) ? $this->_region . '.' : '';
}
/**
* Sends a HTTP request to the queue service using Zend_Http_Client
*
* @param array $params List of parameters to send with the request
* @return Zend_Service_Amazon_Ec2_Response
* @throws Zend_Service_Amazon_Ec2_Exception
*/
protected function sendRequest(array $params = array())
{
$url = 'https://' . $this->_getRegion() . $this->_ec2Endpoint . '/';
$params = $this->addRequiredParameters($params);
try {
/* @var $request Zend_Http_Client */
$request = self::getHttpClient();
$request->resetParameters();
$request->setConfig(array(
'timeout' => $this->_httpTimeout
));
$request->setUri($url);
$request->setMethod(Zend_Http_Client::POST);
$request->setParameterPost($params);
$httpResponse = $request->request();
} catch (Zend_Http_Client_Exception $zhce) {
$message = 'Error in request to AWS service: ' . $zhce->getMessage();
throw new Zend_Service_Amazon_Ec2_Exception($message, $zhce->getCode(), $zhce);
}
$response = new Zend_Service_Amazon_Ec2_Response($httpResponse);
$this->checkForErrors($response);
return $response;
}
/**
* Adds required authentication and version parameters to an array of
* parameters
*
* The required parameters are:
* - AWSAccessKey
* - SignatureVersion
* - Timestamp
* - Version and
* - Signature
*
* If a required parameter is already set in the <tt>$parameters</tt> array,
* it is overwritten.
*
* @param array $parameters the array to which to add the required
* parameters.
*
* @return array
*/
protected function addRequiredParameters(array $parameters)
{
$parameters['AWSAccessKeyId'] = $this->_getAccessKey();
$parameters['SignatureVersion'] = $this->_ec2SignatureVersion;
$parameters['Timestamp'] = gmdate('Y-m-d\TH:i:s\Z');
$parameters['Version'] = $this->_ec2ApiVersion;
$parameters['SignatureMethod'] = $this->_ec2SignatureMethod;
$parameters['Signature'] = $this->signParameters($parameters);
return $parameters;
}
/**
* Computes the RFC 2104-compliant HMAC signature for request parameters
*
* This implements the Amazon Web Services signature, as per the following
* specification:
*
* 1. Sort all request parameters (including <tt>SignatureVersion</tt> and
* excluding <tt>Signature</tt>, the value of which is being created),
* ignoring case.
*
* 2. Iterate over the sorted list and append the parameter name (in its
* original case) and then its value. Do not URL-encode the parameter
* values before constructing this string. Do not use any separator
* characters when appending strings.
*
* @param array $parameters the parameters for which to get the signature.
* @param string $secretKey the secret key to use to sign the parameters.
*
* @return string the signed data.
*/
protected function signParameters(array $paramaters)
{
$data = "POST\n";
$data .= $this->_getRegion() . $this->_ec2Endpoint . "\n";
$data .= "/\n";
uksort($paramaters, 'strcmp');
unset($paramaters['Signature']);
$arrData = array();
foreach($paramaters as $key => $value) {
$arrData[] = $key . '=' . str_replace("%7E", "~", rawurlencode($value));
}
$data .= implode('&', $arrData);
require_once 'Zend/Crypt/Hmac.php';
$hmac = Zend_Crypt_Hmac::compute($this->_getSecretKey(), 'SHA256', $data, Zend_Crypt_Hmac::BINARY);
return base64_encode($hmac);
}
/**
* Checks for errors responses from Amazon
*
* @param Zend_Service_Amazon_Ec2_Response $response the response object to
* check.
*
* @return void
*
* @throws Zend_Service_Amazon_Ec2_Exception if one or more errors are
* returned from Amazon.
*/
private function checkForErrors(Zend_Service_Amazon_Ec2_Response $response)
{
$xpath = new DOMXPath($response->getDocument());
$list = $xpath->query('//Error');
if ($list->length > 0) {
$node = $list->item(0);
$code = $xpath->evaluate('string(Code/text())', $node);
$message = $xpath->evaluate('string(Message/text())', $node);
throw new Zend_Service_Amazon_Ec2_Exception($message, 0, $code);
}
}
}