Amazon Submit Feed Error

Question

I want to update quantity on amazon using Feed Api->Sumbit Feed (_POST_INVENTORY_AVAILABILITY_DATA_)

Here is my code :

$action = 'SubmitFeed';
$path = $_SERVER['DOCUMENT_ROOT'].'/resources/amazon_xml/quantity.xml';

$feed = '<?xml version="1.0" ?><AmazonEnvelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="amzn-envelope.xsd">
                <Header>
                    <DocumentVersion>1.01</DocumentVersion>
                    <MerchantIdentifier>A3QPCC6I4V1QU3</MerchantIdentifier>
                </Header>
                    <MessageType>Inventory</MessageType>
                    <Message>
                        <MessageID>1</MessageID>
                        <OperationType>Update</OperationType>
                        <Inventory>
                            <SKU>6000013953</SKU>
                            <Quantity>1</Quantity>
                        </Inventory>
                    </Message>
                </AmazonEnvelope>';

$feedHandle = fopen($path, 'rw+');
fwrite($feedHandle, $feed);
rewind($feedHandle);

$params = array(
                    'AWSAccessKeyId' => $data['aws_access_key'],
                    'Action' => $action,
                    'Merchant' => $data['merchant_id'],
                    'SignatureMethod' => "HmacSHA256",
                    'SignatureVersion' => "2",
                    'Timestamp'=> gmdate("Y-m-d\TH:i:s.\\0\\0\\0\\Z", time()),
                    'Version'=> "2009-10-01",
                    'MarketplaceIdList.Id.1' => $data['marketplace_id'],
                    'FeedType'=> "_POST_INVENTORY_AVAILABILITY_DATA_",
                    'PurgeAndReplace'=> 'false',
                    'ContentMd5' => base64_encode(md5(stream_get_contents($feedHandle), true))
                );


        // 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.in\n" . $url_string;

        // Sign the request
        $signature = hash_hmac("sha256", $string_to_sign, $data['aws_secret_key'], TRUE);

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



$url = "https://mws.amazonservices.in" . '?' . $url_string . "&Signature=" . $signature;

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL,$url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_TIMEOUT, 15);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
    $response = curl_exec($ch); 

        //echo $url;exit;

        echo '<pre>';
        print_r($response);
        echo '</pre>';
        exit;

But I am getting following response :-

<ErrorResponse xmlns="https://mws.amazonservices.com/">
<Error>
<Type>Sender</Type>
<Code>SignatureDoesNotMatch</Code>
<Message>
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.
</Message>
</Error>
<RequestID>105f88cb-76e2-49c0-9d33-83d6069dd119</RequestID>
</ErrorResponse>

Can somebody please tell me how to send a xml file to api? Or I am doing something wrong ?

quantity.xml file is correct

Update :-

Code is running perfectly on Amazon Scratchpad

Answer 1

Amazon AWS is very fickle in its signature. Version 2 requires that you use RFC 3986 to encode your data

Add the query string components (the name-value pairs, not including the initial question mark (?) as UTF-8 characters which are URL encoded per RFC 3986 (hexadecimal characters must be uppercased) and sorted using lexicographic byte ordering. Lexicographic byte ordering is case sensitive.

Your problem appears to be with your encoding of the signature.

$signature = urlencode(base64_encode($signature));

That will not conform to RFC 3986. PHP has rawurlencode to do that instead.

$signature = rawurlencode(base64_encode($signature));

Answer 2

Your $string_to_sign seems to be missing the local part of the url as third line. In your case, that part is empty, so you'll just need an additional line break.

$string_to_sign = "GET\nmws.amazonservices.in\n\n" . $url_string;