PHP Helper functions for Safe Base64 URL encode

• https://gist.github.com/muffycompo/a378dcfa73c3cf354eb8

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

function base64url_decode($data) { 
  return base64_decode(str_pad(strtr($data, '-_', '+/'), strlen($data) % 4, '=', STR_PAD_RIGHT)); 
} 
?>

• https://github.com/firebase/php-jwt/blob/feb0e820b8436873675fd3aca04f3728eb2185cb/src/JWT.php#L333

 

    /**
     * Decode a string with URL-safe Base64.
     *
     * @param string $input A Base64 encoded string
     *
     * @return string A decoded string
     */
    public static function urlsafeB64Decode($input)
    {
        $remainder = \strlen($input) % 4;
        if ($remainder) {
            $padlen = 4 - $remainder;
            $input .= \str_repeat('=', $padlen);
        }
        return \base64_decode(\strtr($input, '-_', '+/'));
    }
/**
     * Encode a string with URL-safe Base64.
     *
     * @param string $input The string you want encoded
     *
     * @return string The base64 encode of what you passed in
     */
    public static function urlsafeB64Encode($input)
    {
        return \str_replace('=', '', \strtr(\base64_encode($input), '+/', '-_'));
    }