Add Google reCAPTCHA to your PHP site

How it works

See steps below

1. If you are on Ubuntu, install php-curl
2. Register for a key and secret -> https://www.google.com/recaptcha/admin/create
3. Load js with client key -> src=”https://www.google.com/recaptcha/api.js?render=CLIENT_KEY”
4. Add following javascript to you client side html code
   • $(‘#contact’).submit(function(event) {
   • event.preventDefault();
   • grecaptcha.ready(function() {
   • grecaptcha.execute(‘CLIENT_KEY’, {action: ‘submit’}).then(function(token) {
   • $(‘#contact’).prepend(”);
   • $(‘#contact’).prepend(”);
   • $(‘#contact’).unbind(‘submit’).submit();
   • });
   • });
   • });
5. Add following to server
   • define(“RECAPTCHA_V3_SECRET_KEY”, ‘YOUR_SECRET’);
   • /*
   • if (isset($_POST[’email’]) && $_POST[’email’]) {
   • $email = filter_var($_POST[’email’], FILTER_SANITIZE_STRING);
   • } else {
   • // set error message and redirect back to form…
   • header(‘location: index.php’);
   • exit;
   • }
   • */
   • $token = $_POST[‘token’];
   • $action = $_POST[‘action’];
   • // call curl to POST request
   • $ch = curl_init();
   • curl_setopt($ch, CURLOPT_URL,”https://www.google.com/recaptcha/api/siteverify”);
   • curl_setopt($ch, CURLOPT_POST, 1);
   • curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query(array(‘secret’ => RECAPTCHA_V3_SECRET_KEY, ‘response’ => $token)));
   • curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
   • $response = curl_exec($ch);
   • curl_close($ch);
   • $arrResponse = json_decode($response, true);
   • if($arrResponse[“success”] == ‘1’ && $arrResponse[“score”] >= 0.5) {
   • //success
   • }
   • else{
   • //error
   • }

Advertisement