<?php
 
class hasher {
	public function send() {
 
	    $stringToSign = 'test';
	    $key = '123456';
 
	    //Calculate Signature
	    $signature = $this->calculateSignature($stringToSign, $key);
 
	    print_r("StringToSign: " . $stringToSign . PHP_EOL);
	    print_r("Key: " . $key . PHP_EOL);
	    print_r("Signature Caculated: " . $signature . PHP_EOL);
	}
 
	private function calculateSignature($stringToSign, $key) {
 
	    // check signature
	    $hash = strtoupper(hash_hmac('sha256', $stringToSign, hex2bin($key), false));
	    return $hash;
	}
}
 
$h = new hasher;
$h->send();
 

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