PHP public & private key hash

phpApiKeySigning.php

<?php

// Set timezone to UTC
date_default_timezone_set('UTC');

// Provided public and private keys
$publicKey = 'put-your-public-key';
$privateKey = 'put-your-private-key-here';

// Capture the time and package with the public key
$time = time();
$package = $publicKey . "\n" . $time;

// SHA1 hash using the private key and then URL encode the signature
$binSignature = hash_hmac('sha1', $package, $privateKey, true);
$uriSignature = urlencode(base64_encode($binSignature));

// Put together the request URI and URL
$requestUri = "?public_key=" . $publicKey . "&time=" . $time . "&signature=" . $uriSignature;
$requestUrl = "https://api.rapidspike.com/v1/assets" . $requestUri;