V3 Invisible Captcha

v3_captcha.html

<form>

  <input type="hidden" id="g-recaptcha-response" name="g-recaptcha-response" />
  <script src="https://www.google.com/recaptcha/api.js?render=PUBLIC_KEY"></script>
  <script>
      grecaptcha.ready(function() {
          grecaptcha.execute('PUBLIC_KEY', {action: 'homepage'}).then(function(token) {
              document.getElementById('g-recaptcha-response').value = token;
          });
      });
  </script>
  
</form>

v3_captcha.php

<?php 

//Validate recaptcha
$verifyResponse = file_get_contents(
    'https://www.google.com/recaptcha/api/siteverify?secret=SECRET_KEY&response=' . $_REQUEST['g-recaptcha-response']
);
$responseData = json_decode($verifyResponse);
if (!$responseData->success):
    $errors = [ 'Invalid captcha' ];
endif;