(Perl) Walmart Partner API Authentication (Generate a Signature for a Request)

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

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux

use chilkat();

$success = 0;

# 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.
$dt = chilkat::CkDateTime->new();
# 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.
$sbStringToSign = chilkat::CkStringBuilder->new();
$sbStringToSign->Append($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");

$privKey = chilkat::CkPrivateKey->new();
# 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 == 0) {
    print $privKey->lastErrorText() . "\r\n";
    exit;
}

$rsa = chilkat::CkRsa->new();
$success = $rsa->UsePrivateKey($privKey);
if ($success == 0) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

# We want a base64 signature string.
$rsa->put_EncodingMode("base64");

$signatureString = $rsa->signStringENC($sbStringToSign->getAsString(),"SHA256");
if ($rsa->get_LastMethodSuccess() == 0) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

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