in src/MessageValidator.php [143:171]
public function getStringToSign(Message $message)
{
static $signableKeys = [
'Message',
'MessageId',
'Subject',
'SubscribeURL',
'Timestamp',
'Token',
'TopicArn',
'Type',
];
if ($message['SignatureVersion'] !== self::SIGNATURE_VERSION_1
&& $message['SignatureVersion'] !== self::SIGNATURE_VERSION_2) {
throw new InvalidSnsMessageException(
"The SignatureVersion \"{$message['SignatureVersion']}\" is not supported."
);
}
$stringToSign = '';
foreach ($signableKeys as $key) {
if (isset($message[$key])) {
$stringToSign .= "{$key}\n{$message[$key]}\n";
}
}
return $stringToSign;
}