无法从 amazon mws products api 检索结果

Question

使用下面的代码，我能得到的唯一结果是 URL。当我复制并粘贴到浏览器中时，我得到：

<Message>

我们计算的请求签名与您提供的签名不匹配。检查您的 AWS 秘密访问密钥和签名方法。有关详细信息，请参阅服务文档。

正在使用的代码；

<?php
date_default_timezone_set('America/New_York');
define('AWS_ACCESS_KEY_ID', '***');
define('AWS_SECRET_ACCESS_KEY', '***');
define('APPLICATION_NAME', 'test');
define('APPLICATION_VERSION', '1.0');
define ('MERCHANT_ID', '***');
define ('MARKETPLACE_ID', '***');

$base_url = "https://mws.amazonservices.com/Products/2011-10-01";
$method = "GET";
$host = "mws.amazonservices.com";
$uri = "/Products/2011-10-01";

function amazon_xml($searchTerm) {

$params = array(
    'AWSAccessKeyId' => AWS_ACCESS_KEY_ID,
    'Action' => "GetCompetitivePricingForASIN",
    'SellerId' => MERCHANT_ID,
    'SignatureMethod' => "HmacSHA256",
    'SignatureVersion' => "2",
    'Timestamp'=> gmdate("Y-m-d\TH:i:s.\\0\\0\\0\\Z", time()),
    'Version'=> "2011-10-01",
    'MarketplaceId' => MARKETPLACE_ID,
    'Query' => $searchTerm,
    'QueryContextId' => "Automotive");

// Sort the URL parameters
$url_parts = array();
foreach(array_keys($params) as $key)
$url_parts[] = $key . "=" . str_replace('%7E', '~', rawurlencode($params[$key]));
sort($url_parts);

// Construct the string to sign
$url_string = implode("&", $url_parts);
$string_to_sign = "GET\nmws.amazonservices.com\n/Products/2011-10-01\n" . $url_string;

// Sign the request
$signature = hash_hmac("sha256", $string_to_sign, AWS_SECRET_ACCESS_KEY, TRUE);

// Base64 encode the signature and make it URL safe
$signature = urlencode(base64_encode($signature));

$url = "https://mws.amazonservices.com/Products/2011-10-01" . '?' . $url_string .           "&Signature=" . $signature;


$ch = curl_init();
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_URL,$url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
$response = curl_exec($ch);

echo $url;
// return $xml if you still want to parse the data elsewhere
$xml = simplexml_load_string($response);

// return this if you just want the raw XML string
return $xml->asXML();
echo $xml->GetMatchingProductResult->Product->Identifiers->MarketplaceASIN->ASIN;
}

$searchTerm = "B00FNNLBK2";

amazon_xml($searchTerm);



//foreach ($xml->GetMatchingProductResult->Product as $product) {
// do something for each <Product>, such as output the ASIN...

//}



echo $xml;
echo $searchTerm;
echo $xml->GetMatchingProductResult->Product->Identifiers->MarketplaceASIN->ASIN;
echo $url;
?>

我确实多次验证了登录凭据是否正确，没有抽象的前导或尾随空格。

Answer 1

这些参数（例如Query 和QueryContextId）与您尝试调用的Action (GetCompetitivePricingForASIN) 不匹配。它们对应于ListMatchingProducts 操作。

假设你的意思是 ListMatchingProducts 试试这个：

<?php
date_default_timezone_set('America/New_York');
define('AWS_ACCESS_KEY_ID', '***');
define('AWS_SECRET_ACCESS_KEY', '***');
define('APPLICATION_NAME', 'test');
define('APPLICATION_VERSION', '1.0');
define ('MERCHANT_ID', '***');
define ('MARKETPLACE_ID', '***');
function amazon_xml($searchTerm)
{

    $params = array(
        'AWSAccessKeyId' => AWS_ACCESS_KEY_ID,
        'Action' => "ListMatchingProducts",
        'SellerId' => MERCHANT_ID,
        'SignatureMethod' => "HmacSHA256",
        'SignatureVersion' => "2",
        'Timestamp' => gmdate("Y-m-d\TH:i:s.\\0\\0\\0\\Z", time()),
        'Version' => "2011-10-01",
        'MarketplaceId' => MARKETPLACE_ID,
        'Query' => $searchTerm,
        'QueryContextId' => "Automotive"
    );
    $url_parts = array();
    foreach (array_keys($params) as $key)
        $url_parts[] = $key . "=" . str_replace('%7E', '~', rawurlencode($params[$key]));
    sort($url_parts);
    $url_string     = implode("&", $url_parts);
    $string_to_sign = "GET\nmws.amazonservices.com\n/Products/2011-10-01\n" . $url_string;
    $signature = hash_hmac("sha256", $string_to_sign, AWS_SECRET_ACCESS_KEY, TRUE);
    $signature = urlencode(base64_encode($signature));
    $url = "https://mws.amazonservices.com/Products/2011-10-01" . '?' . $url_string . "&Signature=" . $signature;
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
    $response = curl_exec($ch);
    $xml      = simplexml_load_string($response);
    return $xml->asXML();
}
$searchTerm = "B00FNNLBK2";
echo amazon_xml($searchTerm);

您可以在 MWS 文档中找到每个 Action 的相关参数，例如这里： http://docs.developer.amazonservices.com/en_US/products/Products_GetCompetitivePricingForASIN.html

您还可以使用 MWS Scratchpad 查看它们： https://mws.amazonservices.com/scratchpad/index.html