Is there any hook to validate google recaptcha dislayed in wp-signup page [in Wordpress Multisite]

Question

First time working on a directory base WordPress multi-site. I need to add google ReCaptcha in the wp-signup.php page.

I just look at the wp-signup.php file and found do_action( 'signup_extra_fields', $errors ); in the show_user_form function to display a google ReCaptcha in the wp-signup.php page. Here is the code how I added the google ReCaptcha box in the registration form ...

function mcqacnet_example_callback( $errors ) {
    printf( '<div class="g-recaptcha" data-sitekey="%s"></div>', 'my-secret-key' );
}

add_action( 'signup_extra_fields', 'mcqacnet_example_callback', 99);

function mcqacnet_captcha_js_in_footer() {
    echo '<script src="https://www.google.com/recaptcha/api.js" async defer></script>';
}

add_action( 'wp_print_footer_scripts', 'mcqacnet_captcha_js_in_footer' );

Now its time to validate the captcha when a user submits registration form. I looked at the wpmu_signup_user function but no hook define to use.

Please let me know if you have any idea to verify reCaptcha before registration.

Thank you for your time.

Answer 1

The wpmu_validate_user_signup hook might help. Though you'd have to be careful to only apply the reCAPTCHA validation when necessary. For instance, it shouldn't be checked during a REST API request for creating a user.