Analogic\ACME\Lescript::generateKey PHP Method

    private function generateKey($outputDirectory)
    {
        $res = openssl_pkey_new(array("private_key_type" => OPENSSL_KEYTYPE_RSA, "private_key_bits" => 4096));
        if (!openssl_pkey_export($res, $privateKey)) {
            throw new \RuntimeException("Key export failed!");
        }
        $details = openssl_pkey_get_details($res);
        if (!is_dir($outputDirectory)) {
            @mkdir($outputDirectory, 0700, true);
        }
        if (!is_dir($outputDirectory)) {
            throw new \RuntimeException("Cant't create directory {$outputDirectory}");
        }
        file_put_contents($outputDirectory . '/private.pem', $privateKey);
        file_put_contents($outputDirectory . '/public.pem', $details['key']);
    }