Base64URL Support for PHP used for creating JWT (JavaWebToken)

base64url.php

<?php
$header = '{"alg":"HS256","typ":"JWT"}';
$payload = '{"sub":"1234567890","name":"John Doe","role":"user"}';

$encodedHeader = base64url_encode($header);
$encodedPayload = base64url_encode($payload);
$signature = hash_hmac('sha256', "{$encodedHeader}.{$encodedPayload}", 'secret', true);
$signedSignature = base64url_encode($signature);

$jwt = join('.', [$encodedHeader, $encodedPayload, $signedSignature]);
echo $jwt, PHP_EOL;

function base64url_encode($data)
{
    return rtrim(strtr(base64_encode($data), '+/', '-_'), '=');
}

function base64url_decode($data, $strict = false)
{
    return base64_decode(strtr($data, '-_', '+/'), $strict);
}