EricMakesStuff\ServerMonitor\Monitors\SSLCertificateMonitor::downloadCertificate PHP Method

    protected function downloadCertificate($urlParts)
    {
        $streamContext = stream_context_create(["ssl" => ["capture_peer_cert" => TRUE]]);
        $streamClient = stream_socket_client("ssl://{$urlParts['host']}:443", $errno, $errstr, 30, STREAM_CLIENT_CONNECT, $streamContext);
        $certificateContext = stream_context_get_params($streamClient);
        return openssl_x509_parse($certificateContext['options']['ssl']['peer_certificate']);
    }