stripe-php from docs

public function webHookReceiver ($request, $response, $args)
    {
        $config = $this->ci->config;

        $data = $request->getParsedBody();

        Stripe::setApiKey($config['stripe.secret_key']);


        // You can find your endpoint's secret in your webhook settings
        $endpoint_secret = $config['stripe.webhook_key'];

        $payload = $request->getBody();

        $sig_header = $request->getHeaderLine('Stripe-Signature');

        try {
            $event = Webhook::constructEvent(
                $payload, $sig_header, $endpoint_secret
            );
        } catch(\UnexpectedValueException $e) {
            // Invalid payload
            return $response->withStatus(400);
        } catch(\Stripe\Error\SignatureVerification $e) {
            // Invalid signature
            throw $e;
            return $response->withStatus(401);
        }
}