我正在计算一个签名以使Amazon Marketplace API调用，但我不断收到以下错误：

The request signature we calculated does not match the signature you provided. Check your AWS Secret Access Key and signing method. Consult the service documentation for details.

我将签名创建过程包装到一个类中：

namespace App\Marketplace\Amazon;

class Signature

{

protected $signedString;

public function __construct($url, array $parameters, $secretAccessKey)

{

$stringToSign = $this->calculateStringToSign($url, $parameters);

$this->signedString = $this->sign($stringToSign, $secretAccessKey);

}

protected function calculateStringToSign($url, array $parameters)

{

$url = parse_url($url);

$string = "POST\n";

$string .= $url['host'] . "\n";

$string .= $url['path'] . "\n";

$string .= $this->getParametersAsString($parameters);

return $string;

}

protected function sign($data, $secretAccessKey)

{

return base64_encode(hash_hmac('sha256', $data, $secretAccessKey, true));

}

protected function getParametersAsString(array $parameters)

{

uksort($parameters, 'strcmp');

$queryParameters = [];

foreach ($parameters as $key => $value) {

$queryParameters[$key] = $this->urlEncode($value);

}

return http_build_query($queryParameters);

}

protected function urlEncode($value)

{

return str_replace('%7E', '~', rawurlencode($value));

}

public function __toString()

{

return $this->signedString;

}

}

但是我看不到我在哪里错了，我遵循了API中的指南，并查看了Java示例以及旧版Marketplace PHP SDK *。

编辑：这里是我如何使用Signature类：

$version = '2011-07-01';

$url = 'https://mws.amazonservices.com/Sellers/'.$version;

$timestamp = gmdate('c', time());

$parameters = [

'AWSAccessKeyId' => $command->accessKeyId,

'Action' => 'GetAuthToken',

'SellerId' => $command->sellerId,

'SignatureMethod' => 'HmacSHA256',

'SignatureVersion' => 2,

'Timestamp' => $timestamp,

'Version' => $version,

];

$signature = new Signature($url, $parameters, $command->secretAccessKey);

$parameters['Signature'] = strval($signature);

try {

$response = $this->client->post($url, [

'headers' => [

'User-Agent' => 'my-app-name',

],

'body' => $parameters,

]);

dd($response->getBody());

} catch (\Exception $e) {

dd(strval($e->getResponse()));

}

除此之外：我知道市场凭据正确，因为我已经登录到帐户并检索访问密钥，密钥和卖家ID。

*我没有使用SDK，因为它不支持我需要的API调用：SubmitFeed。