(PHP ActiveX) Walmart Partner API Authentication (Generate a Signature for a Request)

Demonstrates how to generate a signature for a Walmart Partner REST API call.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows Note: The php_com_dotnet.dll may need to be enabled inside of php.ini.

<?php

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

$consumerId = 'b68d2a72....';
$baseUrl = 'https://marketplace.walmartapis.com/v2/feeds';
// This is your Base64 encoded private key
$privateEncodedStr = 'MIICeAIBADANBgkqhkiG9w0BAQEFAA......';
$httpMethod = 'GET';

// We need a timestamp in decimal string form representing the number of milliseconds since Jan 01 1970 UTC.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.CkDateTime')
$dt = new COM("Chilkat.CkDateTime");
// Set bLocal = 1 for a timestamp in the local timezone.  Set bLocal = 0 for a UTC timestamp.
$bLocal = 0;
// This gets the timestamp in seconds, not milliseconds.
$timeStampVal = $dt->GetAsUnixTime($bLocal);

// Build the string to sign.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.StringBuilder')
$sbStringToSign = new COM("Chilkat.StringBuilder");
$sbStringToSign->Append($consumerId);
$sbStringToSign->Append('\n');
$sbStringToSign->Append($baseUrl);
$sbStringToSign->Append('\n');
$sbStringToSign->Append($httpMethod);
$sbStringToSign->Append('\n');
$sbStringToSign->AppendInt($timeStampVal);
// We add three zero's so that the timestamp value is in milliseconds.
// We don't care about accuracy down to less than a second.
// All the server cares about is that the request was signed at the current date/time
// within some reasonable margin of error (to account for systems having clocks
// that may be slightly different).
$sbStringToSign->Append('000\n');

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.PrivateKey')
$privKey = new COM("Chilkat.PrivateKey");
// Load the private key into a private key object.
// Note: Technically the private key is not PEM because it lacks the header/footer strings
// used for PEM.  However, the LoadPem method will still accept it and load it correctly.
$success = $privKey->LoadPem($privateEncodedStr);
if ($success != 1) {
    print $privKey->LastErrorText . "\n";
    exit;
}

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Rsa')
$rsa = new COM("Chilkat.Rsa");
$success = $rsa->ImportPrivateKeyObj($privKey);
if ($success != 1) {
    print $rsa->LastErrorText . "\n";
    exit;
}

// We want a base64 signature string.
$rsa->EncodingMode = 'base64';

$signatureString = $rsa->signStringENC($sbStringToSign->getAsString(),'SHA256');
if ($rsa->LastMethodSuccess != 1) {
    print $rsa->LastErrorText . "\n";
    exit;
}

print 'Signature String: ' . $signatureString . "\n";

?>