Craft\AmForms_RecaptchaService::verify PHP Method

    public function verify()
    {
        // Get reCAPTCHA value
        $captcha = craft()->request->getPost('g-recaptcha-response');
        // Get reCAPTCHA secret key
        $secretKey = craft()->amForms_settings->getSettingsByHandleAndType('secretKey', AmFormsModel::SettingRecaptcha);
        if (!$secretKey) {
            return false;
        }
        // Google API parameters
        $params = array('secret' => $secretKey->value, 'response' => $captcha);
        // Set request
        $client = new \Guzzle\Http\Client();
        $request = $client->post('https://www.google.com/recaptcha/api/siteverify');
        $request->addPostFields($params);
        $result = $client->send($request);
        // Handle response
        if ($result->getStatusCode() == 200) {
            $json = $result->json();
            if ($json['success']) {
                return true;
            }
        }
        return false;
    }